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1

Holman, James, i n/a. "Clines, Species and Eucalypts: An Evolutionary Perspective". Griffith University. Australian School of Environmental Studies, 2003. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20030527.124144.

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Two eucalypt clines were examined using morphological, ecophysiological and molecular analyses. The species complexes examined were an ironbark complex (Eucalyptus melanophloia x E. whitei) and a box complex (E. brownii x E. populnea). Both of these complexes demonstrate continuous morphological variation across their clines. The origin of these morphological clines has previously been interpreted as the product of secondary contact between allopatric species. In this study, an analysis of morphological variation across the clines did not identify an increase in trait variance in the intermediate populations, which suggests that previous theories concerning the origin of these clines may not be valid. Genetic structuring in nuclear and chloroplast DNA was examined across the clines to investigate whether the morphological clines were the product of secondary contact between two independent evolutionary lineages, or whether the clines represent a single evolutionary lineage that has undergone primary differentiation. The microsatellite analyses indicated that there was little genetic structuring across either cline, and that there were only low levels of population differentiation. The lack of hierarchical structuring in the distribution of nuclear genetic variation suggests that these clines are unlikely to be the product of recent gene flow between two formerly allopatric species/populations. A nested clade analysis of the JLA+ region of the cpDNA provides additional evidence to reject the null hypothesis that the morphospecies classifications represent distinct evolutionary lineages. Instead the analyses indicate that each cline represents a single cohesion species and a single evolutionary lineage. The phylogeographic distribution of cpDNA haplotypes is likely to have resulted from restricted seed mediated gene flow with isolation by distance. A more cogent explanation for the clines, based on the genetic data, is that they have arisen through the process of continuous morphological diversification that has been promoted by a directional selection gradient. Drought experiments were conducted in the glasshouse to investigate whether differences in physiological performance under water stress helps to explain the maintenance of the ironbark cline. Under increasing water stress, the morphotypes showed differences in their ability to maintain water status and photosynthetic rates, yet there was no obvious pattern to these differences across the cline. Physiological differences are therefore inadequate to explain the maintenance of the ironbark cline and highlight the compensatory role that morphological variation may play in alleviating water stress. The value of adopting the cohesion species concept and a hypothesis-testing framework to assess species status is demonstrated in this study. This framework provided a statistical approach to distinguish independent evolutionary lineages from interspecific populations and provides evidence to refute the current species status of the species complexes studied. Eucalypt classification is predominantly based on morphology, which results in taxonomic classification that may not reflect genealogical relationships. This is due to the disparity between morphological and phylogenetic relationships. I therefore suggest that current presumptions regarding the prevalence and importance of hybridisation within the genus may reflect taxonomic classification. An accurate assessment of the prevalence and importance of hybridisation requires species classification to be based on genealogical relationships.
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2

Holman, James. "Clines, Species and Eucalypts: An Evolutionary Perspective". Thesis, Griffith University, 2003. http://hdl.handle.net/10072/365394.

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Two eucalypt clines were examined using morphological, ecophysiological and molecular analyses. The species complexes examined were an ironbark complex (Eucalyptus melanophloia x E. whitei) and a box complex (E. brownii x E. populnea). Both of these complexes demonstrate continuous morphological variation across their clines. The origin of these morphological clines has previously been interpreted as the product of secondary contact between allopatric species. In this study, an analysis of morphological variation across the clines did not identify an increase in trait variance in the intermediate populations, which suggests that previous theories concerning the origin of these clines may not be valid. Genetic structuring in nuclear and chloroplast DNA was examined across the clines to investigate whether the morphological clines were the product of secondary contact between two independent evolutionary lineages, or whether the clines represent a single evolutionary lineage that has undergone primary differentiation. The microsatellite analyses indicated that there was little genetic structuring across either cline, and that there were only low levels of population differentiation. The lack of hierarchical structuring in the distribution of nuclear genetic variation suggests that these clines are unlikely to be the product of recent gene flow between two formerly allopatric species/populations. A nested clade analysis of the JLA+ region of the cpDNA provides additional evidence to reject the null hypothesis that the morphospecies classifications represent distinct evolutionary lineages. Instead the analyses indicate that each cline represents a single cohesion species and a single evolutionary lineage. The phylogeographic distribution of cpDNA haplotypes is likely to have resulted from restricted seed mediated gene flow with isolation by distance. A more cogent explanation for the clines, based on the genetic data, is that they have arisen through the process of continuous morphological diversification that has been promoted by a directional selection gradient. Drought experiments were conducted in the glasshouse to investigate whether differences in physiological performance under water stress helps to explain the maintenance of the ironbark cline. Under increasing water stress, the morphotypes showed differences in their ability to maintain water status and photosynthetic rates, yet there was no obvious pattern to these differences across the cline. Physiological differences are therefore inadequate to explain the maintenance of the ironbark cline and highlight the compensatory role that morphological variation may play in alleviating water stress. The value of adopting the cohesion species concept and a hypothesis-testing framework to assess species status is demonstrated in this study. This framework provided a statistical approach to distinguish independent evolutionary lineages from interspecific populations and provides evidence to refute the current species status of the species complexes studied. Eucalypt classification is predominantly based on morphology, which results in taxonomic classification that may not reflect genealogical relationships. This is due to the disparity between morphological and phylogenetic relationships. I therefore suggest that current presumptions regarding the prevalence and importance of hybridisation within the genus may reflect taxonomic classification. An accurate assessment of the prevalence and importance of hybridisation requires species classification to be based on genealogical relationships.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
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3

King, Rachel, i n/a. "Spatial Structure and Population Genetic Variation in a Eucalypt Species Complex". Griffith University. Australian School of Environmental Studies, 2004. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20050113.091713.

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In this study, the relative influences of selection, gene flow, and other evolutionary forces on the spatial structure of genetic variation within a eucalypt species complex (the spotted gums: genus Corymbia, section Politaria) were assessed. The study investigated the spatial genetic structure among four putative species of spotted gum (broad-scale), as well as within a single population (fine-scale)of one species, using both molecular and quantitative markers. The spotted gum complex occurs naturally across a range of 2500 km in eastern Australia. Spatial genetic variation within and between the four putative spotted gum species was examined using both chloroplast and nuclear markers. No significant differentiation was found between the three northern species of the complex, C. citriodora, C. variegata and C. henryi. The southern species, C. maculata, shared no haplotypes with any of the three northern species. These results disagree in part with those reported in a previous allozyme based study in which C. henryi was found to be significantly divergent from C. variegata (with which it is sympatric) and more closely aligned with C. maculata. Re-analysis of the allozyme data provided evidence of selection acting at the PGM2 locus within populations of C. variegata and C. henryi. The exclusion of this locus from the data set led to concordance between the cpDNA and nDNA analyses. Restricted gene flow and evidence of isolation by distance were identified as the dominant processes influencing the contemporary distribution of the cpDNA haplotypes. No geographic structure of haplotypes was found and complex genealogical relationships between haplotypes indicated the combined effects of past fragmentation, range expansion and possible long distance dispersal events. The variation and spatial structure in both neutral molecular markers and quantitative genetic traits were compared to explore the relative influences of dispersal and selection within a single eucalypt population. Both mature trees (n=130) from a natural population of C. variegata and their progeny (n=127) were sampled. A very high outcrossing rate (98%) was estimated for the population based on data from seven microsatellite loci. This suggested regular pollen–mediated gene flow into the population, further supported by the observed high levels of genetic diversity and polymorphism. Significant positive spatial structure was found between parent trees occurring up to 150 m apart in the natural forest, although genetic distance between these individuals suggested limited relatedness (i.e. less than half-sib relatedness). The effect of pollen-mediated gene flow appears, therefore, to swamp any effect of nearest neighbour inbreeding which has been reported in other studies of eucalypt populations and has been attributed to limited seed dispersal. Resistance to the fungal disease Sporothrix pitereka (Ramularia Shoot Blight) was measured on progeny from each of the population study trees. Substantial resistance variability was found, along with a high estimate in heritability of resistance (0.44 ± 0.06), indicating significant additive genetic variation within the population. Spatial analysis showed no significant spatial structure with resistant and susceptible genotypes apparently distributed randomly throughout the population. The lack of concordance between the molecular and quantitative markers suggests that there may be a cost to resistance. Temporal variation in the severity of disease outbreaks may have then led to differential selection of seedlings across many generations, maintaining variability in disease resistance and facilitating the apparent random distribution of disease resistant and susceptible genotypes throughout the population. C. variegata is an important commercial forestry species. The identification of strong genetic control in the disease resistance trait, as well as significant adverse genetic and phenotypic correlations between susceptibility and growth traits, will aid future breeding programs. Controlled crosses between resistant genotypes from this population should result in strong genetic gains in both resistance and growth, with little costs associated with inbreeding depression due to the highly outcrossed nature of the population.
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4

King, Rachel. "Spatial Structure and Population Genetic Variation in a Eucalypt Species Complex". Thesis, Griffith University, 2004. http://hdl.handle.net/10072/365496.

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In this study, the relative influences of selection, gene flow, and other evolutionary forces on the spatial structure of genetic variation within a eucalypt species complex (the spotted gums: genus Corymbia, section Politaria) were assessed. The study investigated the spatial genetic structure among four putative species of spotted gum (broad-scale), as well as within a single population (fine-scale)of one species, using both molecular and quantitative markers. The spotted gum complex occurs naturally across a range of 2500 km in eastern Australia. Spatial genetic variation within and between the four putative spotted gum species was examined using both chloroplast and nuclear markers. No significant differentiation was found between the three northern species of the complex, C. citriodora, C. variegata and C. henryi. The southern species, C. maculata, shared no haplotypes with any of the three northern species. These results disagree in part with those reported in a previous allozyme based study in which C. henryi was found to be significantly divergent from C. variegata (with which it is sympatric) and more closely aligned with C. maculata. Re-analysis of the allozyme data provided evidence of selection acting at the PGM2 locus within populations of C. variegata and C. henryi. The exclusion of this locus from the data set led to concordance between the cpDNA and nDNA analyses. Restricted gene flow and evidence of isolation by distance were identified as the dominant processes influencing the contemporary distribution of the cpDNA haplotypes. No geographic structure of haplotypes was found and complex genealogical relationships between haplotypes indicated the combined effects of past fragmentation, range expansion and possible long distance dispersal events. The variation and spatial structure in both neutral molecular markers and quantitative genetic traits were compared to explore the relative influences of dispersal and selection within a single eucalypt population. Both mature trees (n=130) from a natural population of C. variegata and their progeny (n=127) were sampled. A very high outcrossing rate (98%) was estimated for the population based on data from seven microsatellite loci. This suggested regular pollen–mediated gene flow into the population, further supported by the observed high levels of genetic diversity and polymorphism. Significant positive spatial structure was found between parent trees occurring up to 150 m apart in the natural forest, although genetic distance between these individuals suggested limited relatedness (i.e. less than half-sib relatedness). The effect of pollen-mediated gene flow appears, therefore, to swamp any effect of nearest neighbour inbreeding which has been reported in other studies of eucalypt populations and has been attributed to limited seed dispersal. Resistance to the fungal disease Sporothrix pitereka (Ramularia Shoot Blight) was measured on progeny from each of the population study trees. Substantial resistance variability was found, along with a high estimate in heritability of resistance (0.44 ± 0.06), indicating significant additive genetic variation within the population. Spatial analysis showed no significant spatial structure with resistant and susceptible genotypes apparently distributed randomly throughout the population. The lack of concordance between the molecular and quantitative markers suggests that there may be a cost to resistance. Temporal variation in the severity of disease outbreaks may have then led to differential selection of seedlings across many generations, maintaining variability in disease resistance and facilitating the apparent random distribution of disease resistant and susceptible genotypes throughout the population. C. variegata is an important commercial forestry species. The identification of strong genetic control in the disease resistance trait, as well as significant adverse genetic and phenotypic correlations between susceptibility and growth traits, will aid future breeding programs. Controlled crosses between resistant genotypes from this population should result in strong genetic gains in both resistance and growth, with little costs associated with inbreeding depression due to the highly outcrossed nature of the population.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Australian School of Environmental Studies
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5

Oliveira, Nádia Cristina de [UNESP]. "Biologia de Gonipterus scutellatus (Coleoptera: Curcu- lionidae) em Eucalyptus spp. em diferentes temperaturas". Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/105409.

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Gonipterus scutellatus, conhecido como o gorgulho do eucalipto, é de origem australiana e considerada mundialmente a principal espécie de besouro desfolhador de Eucalyptus. Este trabalho teve por objetivos estudar o desenvolvimento de G. scutellatus em diferentes espécies e híbridos de Eucalyptus (E. camaldulensis, E. grandis, E. urophylla e dois híbridos de E. grandis x E. urophylla conhecidos como urograndis) em diferentes temperaturas (18°C, 22°C, 26°C e 30°C). Os resultados demonstraram que o desenvolvimento biológico de G. scutellatus foi dependente do hospedeiro e da temperatura. E. urophylla foi o mais adequado ao desenvolvimento do gorgulho enquanto E. grandis afetou negativamente sua biologia. Para os híbridos, os resultados foram intermediários entre os obtidos nessas duas espécies. O período de desenvolvimento de G. scutellatus foi inversamente proporcional à temperatura. Foi observado que a melhor temperatura foi a 26°C enquanto 30°C foi letal ao desenvolvimento biológico desta espécie.
Gonipterus scutellatus, known as eucalyptus snout beetle, is from Australia and considered the main species of Eucalyptus defoliator beetle world-wide. This paper deals with the development of the G. scutellatus reared on different species and hybrids of Eucalyptus (E. camaldulensis, E. grandis, E. urophylla and two hybrids of E. grandis X E. urophylla, the so called urograndis) at different temperatures (18°C, 22°C, 26°C and 30°C). The results demonstrated that G. scutellatus biological development was host and temperature dependent, E. urophylla was the most suitable for the weevil development while E. grandis affected negatively its biology. As to hybrids, the results were intermediary between the obtained on these two species. The development period of G. scutellatus was inversely proportional to the temperature. It was observed that 26°C was the best temperature, while 30°C was lethal to the biological development of this species.
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6

Oliveira, Nádia Cristina de 1975. "Biologia de Gonipterus scutellatus (Coleoptera: Curcu- lionidae) em Eucalyptus spp. em diferentes temperaturas /". Botucatu : [s.n.], 2006. http://hdl.handle.net/11449/105409.

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Orientador: Carlos Frederico Wilcken
Banca: Wilson Badiali Crocomo
Banca: Evoneo Berti Filho
Banca: Nilton José de Sousa
Banca: Edson Tadeu Iede
Resumo: Gonipterus scutellatus, conhecido como o gorgulho do eucalipto, é de origem australiana e considerada mundialmente a principal espécie de besouro desfolhador de Eucalyptus. Este trabalho teve por objetivos estudar o desenvolvimento de G. scutellatus em diferentes espécies e híbridos de Eucalyptus (E. camaldulensis, E. grandis, E. urophylla e dois híbridos de E. grandis x E. urophylla conhecidos como urograndis) em diferentes temperaturas (18°C, 22°C, 26°C e 30°C). Os resultados demonstraram que o desenvolvimento biológico de G. scutellatus foi dependente do hospedeiro e da temperatura. E. urophylla foi o mais adequado ao desenvolvimento do gorgulho enquanto E. grandis afetou negativamente sua biologia. Para os híbridos, os resultados foram intermediários entre os obtidos nessas duas espécies. O período de desenvolvimento de G. scutellatus foi inversamente proporcional à temperatura. Foi observado que a melhor temperatura foi a 26°C enquanto 30°C foi letal ao desenvolvimento biológico desta espécie.
Abstract: Gonipterus scutellatus, known as eucalyptus snout beetle, is from Australia and considered the main species of Eucalyptus defoliator beetle world-wide. This paper deals with the development of the G. scutellatus reared on different species and hybrids of Eucalyptus (E. camaldulensis, E. grandis, E. urophylla and two hybrids of E. grandis X E. urophylla, the so called urograndis) at different temperatures (18°C, 22°C, 26°C and 30°C). The results demonstrated that G. scutellatus biological development was host and temperature dependent, E. urophylla was the most suitable for the weevil development while E. grandis affected negatively its biology. As to hybrids, the results were intermediary between the obtained on these two species. The development period of G. scutellatus was inversely proportional to the temperature. It was observed that 26°C was the best temperature, while 30°C was lethal to the biological development of this species.
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7

Ranzini, Maurício. "BALANCO HIDRICO, CICLAGEM GEOQUIMICA DE NUTRIENTES E PERDAS DE SOLO EM DUAS MICROBACIAS REFLORESTADAS COM Eucalyptus saligna Smith, NO VALE DO PARAIBA, SP". Universidade de São Paulo, 1990. http://www.teses.usp.br/teses/disponiveis/11/11142/tde-20042016-113241/.

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Objetivou-se com este estudo avaliar o efeito de preparos de solo diferenciados, aplicados em duas bacias hidrográficas experimentais reflorestadas com eucalipto, sobre o balanço hídrico, o escoamento direto, a qualidade da água, a ciclagem de nutrientes e as perdas de solo. As microbacias estão localizadas no Vale do Paraíba, Município de Santa Branca, Estado de São Paulo. Fazem parte da Fazenda Bela Vista III, que pertence à empresa FLORIN - Florestamento Integrado S.A. A microbacia A tem uma área de 7,2 ha, sendo 239 m2 (3,3% da área) de mata ciliar, com uma declividade média de 19, 6%; enquanto a área da microbacia B é de 5,5 ha, com 117 m2 (2,1% da área) de mata ciliar e a declividade média de 28,9%. As duas áreas foram plantadas com Eucalyptus saligna Smith, porém tiveram preparos de solo diferenciados: na microbacia A, o preparo de solo consistiu em roçada, queimada, e aração a 20 cm de profundidade com arado de disco; na microbacia B, o preparo de solo consistiu apenas em roçada, queimada, e coveamento manual. As microbacias tiveram as matas ciliares preservadas. A precipitação foi medida com um pluviógrafo tipo Helmann, de rotação semanal, que propiciou a tabulação dos dados de precipitacão diária, para as duas microbacias, três pluviômetros tipo Ville de Paris e um pluviômetro de acrílico marca Fretin, que contituiram a rede para a determinação, pela média aritmética, da precipitação semanal para as bacias. Para a amostragem de água das chuvas visando as análises físico-químicas foram instalados cinco coletores apropriados ao longo das duas microbacias. O deflúvio das microbacias foi obtido através da medição contínua da vazão, sendo utilizados dois linígrafos modelo Hidrologia, instalados um em cada estação fluviométrica. As amostras do deflúvio, em ambas microbacias, foram coletadas no vertedouro, com garrafas de polietileno, em intervalos semanais. As determinações dos elementos K+, Ca++ , Mg++, Fe++ e Na+, como parte da análise da água da chuva e do deflúvio, foram realizadas por meio de espectrofotômetro de absorção atômica. O N03- e P04-3 foram analisados por colorimetria, pelos métodos da brucina e do fosfomolibdato, respectivamente . O NH4+ foi determinado por titulação pelo método da destilação. Seguindo-se as normas da AMERICAN PUBLIC HEALTH ASSOCIATION (1976), foram realizadas as análises de turbidez, condutividade elétrica e pH. Os valores da alcalinidade foram obtidos por titulação, e os valores de cor, por colorimetria, tendo-se como escala colorimétrica uma solução de platino-cobalto. A perda de solo foi calculada a partir da concentração semanal de sedimento, mais aquelas oriundas de chuvas isoladas. O material sedimentado, por ter se mostrado em muita pequena quantidade e de difícil quantificação, não foi mensurado. No entanto, acredita-se que a sua ausência na totalização da perda de solo não interfira, de forma significativa, na análise da comparação relativa das perdas de solo entre as duas microbacias estudadas. A microbacia B apresenta condições que favorecem o escoamento superficial, possibilitando a existência de áreas passiveis de erosão e formação de voçorocas. Já a microbacia A possui condições mais permeáveis do solo, as quais favorecem o escoamento subsuperficial. A evapotranspiração para a microbacia A foi de 82,8%, enquanto a microbacia B, durante o período estudado, mostrou uma taxa de 44,4%. Os fluxos mensais de nutrientes mostraram que existe um ganho de NH4+, NO3- e PO4-3 para ambas microbacias. O Ca++, Mg++, Fe++ e o Na+ apresentaram um balanço negativo . Já o K+ revelou um ganho na microbacia A, ao contrário da microbacia B. A contribuição relativa da precipitação ocorrida na área experimental em relação ao teor de nutrientes contidos numa árvore inteira, num tronco com casca e noutro sem casca, mostrou que a entrada de nitrogênio via precipitação foi significativa, enquanto as entradas de P04-3, K+, Ca++ e Mg++ estiveram abaixo do requerido, principalmente, se a exploração da árvore inteira for considerada. A produção de sedimento em suspensão foi 2,5 vezes maior na microbacia B do que na microbacia A. Já a contribuição média devida às chuvas, nas perdas totais de solo da microbacia A atingiu apenas 4,89%; na microbacia B esta contribuição chegou a 40,56%. As medidas de preparo de solo e de cultivo mínimo, baseados na declividade média do terreno e na textura de solo; além da preservação das matas ciliares, adotadas previamente pela empresa, estão, aparentemente, sendo eficientes na conservação do solo, conforme os dados analisados no presente estudo.
The goal of this study is to estimate the effects of different managements applied to two experimental catchments with eucalypt plantations over the water balance, the nutrient cycling and the soil loss. The small catchments are located in Paraíba River Valley, in the Municipatily of Santa Branca, São Paulo State. They are part of III Bela Vista Forest Farm, from FLORIN - Integrated Forested company S. A. The A catchment has an area of 7.2 ha, with an average slope of 19.6%, while the area of the B catchment is 5.5 ha, and its average slope is 28.9%. Both areas were planted with Eucalyptus saligna Smith, but they had different site preparation: at catchment A, the plantation was preceded by a mechanical method of site preparation (plowing without harrowing); at catchment B. the plantation was established manually without soil preparation (slash burning). The small catchment the had riparian ecosystem preserved. The precipitation was measured with a Helmann type recording gage, with a week rotation, and four non-recording raingages. Average by arithmetic mean precipitation for the catchments was determined. Five adequate collectors were installed for the rainfall sampling aiming at the physical-chemical analysis. Streamflow was measured with 90° V-notch weirs containing a stage recorders installed one in each gaging station. The streamflow samples, in both small catchments, were collect weekly at the weir with polyethylene bottles. The determinations of K+, Ca++, Mg++, Fe++ and Na+ elements, as part of the rainfall and of the streamflow analysis, were made by spectrophotometry. N03- and P04-3 were analysed by colorimetry, using the brucina and phosphomolybdate methods, respectively. The NH4+ was analyzed by the distillation method. The loss of soil was calculated from the weekly sediment concentration. Additionally, the weirs were adapted with a semi-automatic sampling device to collect samples from higher stage to storm discharge. The sedimented material, being very tiny and in small quantity, was not measured. However, we believe that the absence at this part in the totalization of soil loss does not interfere in an essencial way in the comparative analysis of the soil loss between the two catchments. Catchment B presents conditions that favors surface runoff, allowing the existence of possible areas of erosion and gully formation. But catchment A has more permeable soil, which are favourable to the subsurface runoff. Evapotranspiration was 82.8% of the annual precipitation in catchment A, while for catchment B this percentage was 44.4%. The monthly flows of nutrients showed a gain of NH4+, N03- and P04-3 in both catchments. For Ca++, Mg++, Fe++ and the Na+ the balance was negative. But for K+ there was a gain in catchment A, and a loss in catchment B. The relative contribution of nutrient input in precipitation measured in this experimental area, in comparison with the nutrient contents of a whole tree, a trunk with bark, and a trunk without bark, showed that the input of nitrogen by precipitation was significant, while the inputs of P04-3, K+, Ca++ and Mg++ were below required amount, mainly if the exploration of the whole tree was considered. The production of suspended sediment was 2.5 times greater in the catchment B than in catchment A. But the average contribution due to the rain, in the total loss of the soil in catchment A reached only 4.89%; in the catchment B this contribution reached 40.56%. The method of site preparation and minimal cultivation, besides the policy of preserving riparian ecosystem, used routinely by the company are apparently being confirmed as adequate for soil and water conservation in the region.
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8

Soares, Lucas Kelvin Dias. "Manejo da copa diminui o fator de afilamento do fuste e altera fisiologia foliar de Eucalyptus urophylla". Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-25042017-151747/.

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A pluridade de características de espécies nativas, aliada a leis que limitam sua exploração, acarreta na necessidade de estabelecimento de novas espécies capazes de suprir a demanda madeireira brasileira. Os Eucalyptus spp. são altamente produtivos sob clima tropical, sendo extensamente plantados no país para diversas finalidades, em especial papel e celulose, energia, painéis e serraria, entretanto, pouca ênfase tem sido dada a esta última, devido ao horizonte longo de planejamento, dificuldades no processamento primário e defeitos na madeira apresentados pelas espécies mais produtivas do gênero. Visando traçar estratégias que minimizem essas dificuldades, analisamos o efeito de 2 formas de manipulação de copa - destopo e desrama -, sob diferentes regimes de luminosidade, em parâmetros da copa e do tronco em híbridos de Eucalyptus urophylla dos 11 aos 23 meses de idade. Tanto o destopo quanto a desrama afetaram negativamente o incremento diamétrico e volumétrico do híbrido, entretanto, árvores destopadas sob níveis maiores de luminosidade exibiram fatores de afilamento menores, quando comparadas ao tratamento Controle. Dentro do mesmo regime de luminosidade, árvores desramadas também apresentaram fatores de afilamento inferiores. Apesar de sua alta demanda por luz, o híbrido foi capaz de alterar sua estrutura foliar de acordo com o nível de luminosidade: árvores sob regimes de luminosidade reduzida adaptaram suas folhas à sombra (folhas de sombra), enquanto que àquelas sem limitação de luminosidade folhas adaptadas ao sol (folhas de sol). Brotações em resposta ao destopo se resumiram à brotações epicórmicas próximo à seção destopada.
The diversity of characteristics of native species, allied to laws that limit their exploration, reinforces the need of establishing news species to supply the national wood demand. The Eucalyptus spp. are highly productive under tropical whether, being extensively planted in the country to many finalities, especially paper, pulp, energy, panels and sawn wood, however, low attention is being given to the last due to the long term planning, difficulties in the primary processing and wood blemishes present in the most productive species of the gender. Aiming to trace strategies that minimize these hardships, we analyzed the effects of two forms of crown manipulation - topping and pruning -, under different light patterns, in parameters of crown and bole of Eucalytpus urophylla hybrids from 11 to 23 months of age. Both topping and pruning impacted negatively the diametric and volumetric increment, although topped trees showed smaller taper when compared to the Control treatment. Within the same light pattern pruned trees also presented smaller taper. Although the hybrid demands high amounts of light, it was capable of altering its foliage structure according to the light level: trees under reduced light adapted its leaves to shadow (\"shadow leaves\"), while those without light limitation leaves adapted to sun (\"sunleaves\"). Shoots in response to topping were resumed to epicormic shoots close to the topped section.
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9

Domingues, Rui Miguel de Andrade. "Extraction and purification of triterpenic acids from eucalypt bark". Doctoral thesis, Universidade de Aveiro, 2012. http://hdl.handle.net/10773/10704.

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Doutoramento em Engenharia Química
A indústria da pasta e do papel é um sector importante da economia mundial, particularmente a que assenta em espécies de Eucalyptus. No entanto, essas indústrias geram quantidades significativas de correntes secundárias de subprodutos e resíduos de biomassa que podem ser exploradas em aplicações de valor acrescentado em vez de serem queimadas para produção de energia. Um exemplo nobre pode ser a produção de ácidos triterpénicos com estruturas dos tipos lupano, oleanano e ursano, dada a sua abundância em alguns destes resíduos, em particular na casca, adotando o conceito de biorrefinaria integrada numa fábrica de pasta. Estes compostos são conhecidos pelas suas inúmeras actividades biológicas, por exemplo, antioxidante, anti-inflamatória e antitumoral, e podem encontrar aplicações em produtos de elevado valor, tais como cosméticos, nutracêuticos ou farmacêuticos. Neste sentido, o estudo das potencialidades das cascas das espécies de eucalipto mais exploradas enquanto fontes de compostos triterpénicos é um tópico relevante. Por conseguinte, foram analisados e comparados em pormenor os teores e composições em ácidos triterpénicos (TTAs) das cascas externas de várias espécies de eucalipto (E. globulus, E. grandis, E. urograndis, E. maidenii e E. nitens). Os teores dos principais TTAs identificados nestas espécies variaram entre 4.5 g/kg no E. urograndis e 21.6 g/kg no E. nitens. Observou-se que as cascas externas de Eucalyptus de zonas temperadas e Mediterrânicas, nomeadamente E. nitens e E. globulus, são mais ricas em TTAs que as espécies de regiões tropicais e subtropicais. Além disso, a casca externa do E. globulus é claramente a mais rica em ácidos com estruturas do tipo ursano enquanto a do E. nitens é a mais rica em ácidos do tipo oleanano e lupano. Estes resultados levaram-nos a estudar a extração dos TTAs da casca de Eucalyptus, bem como a sua posterior concentração e purificação, a qual foi efetuada por extração sólido-líquido convencional combinada com a precipitação de solutos, e por extração com fluidos supercríticos (SFE). No que diz respeito à primeira abordagem referida, foi desenvolvido neste trabalho um método patenteado que permite obter extratos enriquecidos em TTAs das cascas de eucalipto baseado em tecnologias disponíveis no imediato. Em relação à segunda abordagem, e de forma a apostar em processos de baixo impacto ambiental exigidos pelas biorrefinarias do futuro, a SFE surge como uma opção natural. Assim, foi efetuada a SFE da casca caduca do E. globulus com dióxido de carbono puro e modificado para recuperar a fração de TTAs, e os resultados foram comparados com os obtidos por extração em Soxhlet com diclorometano. Foram realizados estudos preliminares sobre a influência da pressão (100-200 bar), a adição de co-solvente (0, 5 e 8% m/m de etanol), e operação em múltiplos passos a fim de avaliar a aplicabilidade da alternativa supercrítica para a sua produção eficiente e selectiva. Os resultados destacaram a influência da pressão e o importante papel resumo (cont.) desempenhado pelo co-solvente neste processo, cujo efeito foi mais relevante do que o aumento da pressão em várias dezenas de bar. Este trabalho foi depois otimizado, usando o planeamento factorial de experiências e a metodologia de superfícies de resposta, para analisar a influência da temperatura (40-60 ºC), pressão (100-200 bar), e teor de etanol (0.0-5.0% m/m) na recuperação dos TTAs e respectiva concentração nos extractos. Nestes intervalos, as melhores condições de operação encontradas foram 200 bar, 40 °C e 5% de etanol, para as quais os modelos de regressão estatisticamente validados previram um rendimento de extração de 1.2% com 50% de concentração em TTAs, correspondendo ao rendimento em TTAs de 5.1 g/kg de casca e uma recuperação de 79.2% comparativamente ao valor do Soxhlet. Os TTAs livres e acetilados apresentaram tendências de extracção bastante distintas devido às suas diferentes afinidades para o CO2 causadas pelas diferentes polaridades: os derivados acetilados aproximam-se de um patamar máximo a cerca de 200 bar e 5% de etanol, enquanto a extração dos TTAs livres apresenta uma tendência sempre crescente no intervalo de condições estudado. Foram também medidas curvas cumulativas de SFE da casca do E. globulus de forma a analisar o comportamento cinético do processo em termos de rendimento total, rendimento em TTAs, rendimento em TTAs livres, rendimento em TTAs acetilados, e concentração dos TTAs nos extractos. Foi analisada a influência da pressão, temperatura, teor de co-solvente e caudal do dióxido de carbono sobre as respostas anteriores. Os dados experimentais foram modelados com os modelos Logístico, de Dessorção, de Placa Plana Simples, e de Difusão. Na globalidade, os resultados confirmaram que a pressão e o teor de etanol têm um efeito significativo sobre as curvas de extração, os rendimentos finais e as concentrações dos extratos, e mostraram a presença de limitações externas à transferência de massa em alguns ensaios. Mais uma vez, as famílias individuais de TTAs livres e acetilados apresentaram diferentes tendências de extracção. A modelação permitiu-nos confirmar não só o importante papel desempenhado pela difusão intraparticular na SFE, mas também a contribuição da resistência no filme em alguns ensaios. Após a análise de todos os resultados, foi efetuado um ensaio em duas etapas em série, possibilitando o enriquecimento do teor em TTAs no extracto devido às diferentes condições adotadas em cada etapa. Por último, um éster metílico de um ácido triterpénico do tipo oleanano - morolato de metilo - foi identificado pela primeira vez enquanto componente da casca de Eucalyptus na casca externa do Eucalyptus grandis x globulus, onde ocorre em teores elevados. A sua extração com CO2 supercrítico foi também realizada, visando a conceção de uma alternativa de extração ambientalmente benigna para este composto. A 200 bar e 60 ºC, a remoção do morolato de metilo atingiu um patamar às 6 h para 5.1 kg h-1 de CO2 / kg de casca. Em geral, e de forma semelhante à SFE da casca do E. globulus, os TTAs acetilados foram mais significativamente extraídos quando comparados com os seus ácidos livres, o que está diretamente relacionado com a natureza menos polar destas moléculas. O trabalho apresentado nesta tese é uma contribuição para a valorização de uma corrente de biomassa com baixo valor na indústria de pasta em duas vertentes complementares. Por um lado, aumentou o conhecimento da composição lipofílica das cascas de Eucalyptus spp. com interesse comercial para a produção de pasta, destacando o seu potencial enquanto fontes de ácidos triterpénicos. Por outro lado, foram desenvolvidos dois processos alternativos e facilmente integráveis numa fábrica de pasta para a sua exploração a partir da casca: um baseado em tecnologias convencionais bem estabelecidas a nível industrial, prevendo a sua aplicação a curto prazo, e um outro baseado na SFE, seguindo as tendências das futuras biorrefinarias.
The pulp and paper industries are an important sector in the world economy, particularly those based on Eucalyptus species. However these industries generate substantial amounts of by-products and biomass side streams which may be exploited in added value applications, rather than being burned for energy production. A noble example could be the production of triterpenic acids with lupane, oleanane, and ursane skeletons, by adopting the concept of a biorefinery integrated into a pulp mill, since they are highly abundant in some of those residues, particularly in the bark. These compounds are known by their innumerous biological properties, e.g. antioxidant, anti-inflammatory or antitumor, and can find valuable applications in products such as nutraceuticals, cosmetics or pharmaceuticals. In this sense, the study of the potentialities of the barks of the most exploited Eucalyptus species as sources of triterpenic compounds is an important issue. Accordingly, the analysis of the triterpenic acids (TTAs) composition of the outer barks of several Eucalyptus species (E. globulus, E. grandis, E. urograndis, E. maidenii and E. nitens) was carried and compared in detail. The contents of the main TTAs identified in these species varied between 4.5 g/kg in E. urograndis and 21.6 g/kg in E. nitens. It was observed that the outer barks from Eucalyptus of temperate and Mediterranean zones, namely E. nitens and E. globulus, are richer in TTAs than those species from sub-tropical and tropical regions. Furthermore, E. globulus outer bark is clearly the richest in ursane acids while E. nitens is the richest in oleanane and lupane acids. These results induced us to investigate the TTAs extraction from Eucalyptus bark and their further concentration and purification, which were accomplished by conventional solid-liquid extraction combined with solutes precipitation, and by supercritical fluid extraction (SFE). With respect to the first mentioned approach, a patented method for obtaining extracts enriched in TTAs from Eucalyptus barks based on readily available technologies was developed in this work. Concerning the second approach, in order to contribute for the low environmental impact processes required by future biorefineries, the SFE arises as a natural option. Hence, the SFE of E. globulus deciduous bark was performed with pure and modified carbon dioxide to recover the TTAs fraction, and the results were compared with those obtained by Soxhlet extraction with dichloromethane. The influence of pressure (100-200 bar), co-solvent content (0, 5 and 8 wt.% of ethanol), and multistep operation were preliminary studied in order to evaluate the applicability of the supercritical alternative for their selective and efficient production. Results pointed out the influence of pressure and the important role played by co-solvent, whose effect was more important than increasing pressure by several tens of bar. This work was further optimized using factorial design of experiments and the response surface abstract (cont.) methodology to analyze the influence of temperature (40-60 ºC), pressure (100- 200 bar), and ethanol content (0.0-5.0 wt.%) upon TTAs recovery and concentration in extracts. In these intervals, the best operating conditions found were 200 bar, 40ºC and 5% ethanol, for which the statistically validated regression models provided an extraction yield of 1.2% and TTAs concentration of 50%, which correspond to TTAs yield of 5.1 g/kg of bark and a recovery of 79.2% in comparison to the Soxhlet value. The trends of the free and acetylated TTAs were very different, due to their distinct CO2-philic character caused by dissimilar polarities: the acetyl derivatives approached a plateau near 200 bar and 5% ethanol, while the free TTAs extraction always increased in the range of the conditions studied. The cumulative curves of SFE of E. globulus bark were also measured in order to examine the kinetic behavior of this process in terms of total yield, TTAs yield, free TTAs yield, acetylated TTAs yield, and TTAs concentration in the extracts. The influence of pressure, temperature, co-solvent content, and carbon dioxide flow rate upon the previous responses was analyzed. The experimental curves were modeled with Logistic, Desorption, Simple Single Plate, and Diffusion models. In the whole, results confirmed that pressure and ethanol content imparted a significant effect upon extraction curves, final yields, and extracts concentrations, and showed that external limitations to mass transfer affected some runs. Once again, the individual families of free and acetylated TTAs exhibited distinct extraction trends. Modeling allowed us to confirm not only the major role played by intraparticle diffusion upon the SFE but also the contribution of film resistance in some assays. After analyzing all results, a two-step experiment in series has been performed, making possible to enrich the TTAs content in the extract due to the distinct conditions adopted in each stage. Finally, a highly abundant oleanane type triterpenic acid methyl ester – the methyl morolate – was identified for the first time as a component of Eucalyptus bark tissues in outer barks of Eucalyptus grandis x globulus. Its supercritical CO2 extraction was also carried out, aiming at designing an environmentally friendly extraction alternative for this compound. At 200 bar and 60 ºC, the methyl morolate removal attained a plateau at 6 h for 5.1 kg h-1 of CO2 / kg of bark. In the whole, and similarly to the SFE of E. globulus bark, the acetylated TTAs obtained were more significantly extracted when compared to their free acids, which is directly related with the less polar nature of the former molecules. The work presented in this thesis is a contribution for the upgrading of a low value biomass stream from the pulp industry from two complementary points of view. In one hand, it increased the knowledge of the lipophilic composition of the bark of Eucalyptus spp. with commercial interest for pulpwood, highlighting their potential as triterpenic acids sources. On the other hand, two alternative processes were developed for their exploitation from the bark, being easily integrated within a pulp mill: one based on well establish conventional technologies foreseeing its short term implementation, and another based on SFE, following the trends of future biorefineries.
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10

George, Amy Kathryn. "Eucalypt regeneration on the Lower Murray floodplain, South Australia". Connect to this title online, 2004. http://hdl.handle.net/2440/37706.

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Vegetation along the River Murray floodplains has been shown to be in a severe state of decline. This decline is amplified by the impositions of river regulation. In South Australia, where vegetation losses have been great, regeneration is limited and may result in not only individual tree losses but also widespread population decline. This study aimed to examine the relationship between river flows and the regeneration process in populations of Eucalyptus camaldulensis and Eucalyptus largiflorens. The current structure of the populations was examined to determine if a viable number of varying age-classed trees were present. Tree surveys conducted at Banrock Station determined that while densities were low for both species, E. camaldulensis had a more sustainable population structure than E. largiflorens. Growth stages for both species illustrated highly clumped distribution, which is believed to correspond with river flooding magnitudes and frequencies. To address the potential link between tree distribution and flooding within the River Murray, a hydrological analysis was conducted for Banrock Station using river flows at the South Australian border from 1900 to 2003. The amount of time growth stages for each species were inundated was found to be greatly reduced under regulated flows compared to natural flows. This has resulted in shifted localized regeneration patterns corresponding with E. camaldulensis' greater demand for inundation than E. largiflorens. Moderate magnitude flows have been most impacted by regulation, and consequently these are the very flows needed for floodplain tree population maintenance. Flowering and seed fall for E. camaldulensis and E. largiflorens were monitored at Banrock Station for 22 months to identify losses in reproductive potential resulting from tree decline. While seed viability was not affected by vigour, trees with visually reduced vigour were found to produce less fruit and had reduced seed fall, as well as a reduced rate of fruit development. Dendrochronological techniques were applied to floodplain trees. Age and size relationships could be established, implying that such techniques can be applied in South Australia to high quality sites. Growth responses within cohorts were similar and easily matched between individuals illustrating cyclic, but not necessarily seasonal correlations. This work verified the preferential selection of younger trees for dendroecological studies, and identified a relationship between on moderate flows and measurable girth expansion in both floodplain tree species.
Thesis (Ph.D.)--School of Earth and Environmental Sciences, 2004.
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11

Neto, Paulo Pompermayer. "Utilização da videografia aérea na detecção de áreas com deficiências nutricionais em plantios de eucalipto". Universidade de São Paulo, 2002. http://www.teses.usp.br/teses/disponiveis/11/11142/tde-13082002-144150/.

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A videografia aérea é uma técnica que vem sendo utilizada nos EUA para avaliação, detecção e prevenção de problemas na agricultura, agricultura de precisão e no manejo de áreas naturais. Um dos motivos para o emprego desta técnica é o seu baixo custo para a obtenção das imagens e a rapidez com que podem ser captadas, processadas e analisadas. Assim sendo, o objetivo deste trabalho foi verificar a utilidade da técnica videográfica no levantamento de problemas nutricionais em plantações de eucalipto, utilizando-a como ferramenta no monitoramento nutricional, tornando-o mais preciso e menos dispendioso que os métodos utilizados atualmente. Para isto, instalou-se um experimento com tratamentos de subtração de nutrientes com a finalidade de verificar a potencialidade da videografia aérea como técnica para distinguir os tratamentos com deficiência nutricional nos plantios deeucalipto. Foram obtidas imagens nos espectros verde, azul, vermelho e infravermelho próximo, 12 meses após o plantio. Essas imagens foram capturadas com duas câmeras S-VHS: uma capaz de captar a faixa do espectro visível (400 - 700 nm) e, outra capaz de captar a faixa do espectro visível mais infravermelho próximo (400 – 1100 nm). Nestas câmeras foram também utilizados filtros de subtração para separar as faixas do espectro a serem trabalhadas. Além disso, com a utilização do software ENVI, foi feita uma análise dos valores de pixels de cada parcela, obtendo-se os valores mínimos, médios, máximo e o desvio padrão da média. Estes valores foram, então, comparados e agrupados conforme análise estatística multivariada, buscando encontrar relações entre os dados das imagens e os tratamentos. Relações significativas entre os dados dendrométricos e os dados de pixel foram encontradas para as imagens obtidas a 1500 metros de altitude pela câmera COHU nos espectros azul e infravermelho próximo e, pela câmera PANASONIC no espectro vermelho.
The aerial videography is a technique that has been used in the USA to evaluate, detect and prevent agricultural problems, as well as in the handling of natural areas. One of the reasons for the employment of this technique is its low cost for obtaining the images and the speed with that they can be captured, processed and analyzed. The aim of this work was to verify the usefulness of the videography technique in detecting nutritional deficiency in eucalyptus plantations, using it as a tool in the nutritional monitoring, turning it more precise and less costly than the methods used at present. For this, an experiment was settled with treatments of subtraction of nutrients with the purpose of verifying the potentiality of the aerial videography as technique to distinguish the treatments with nutritional deficiency in eucalyptus plantation. Images were obtained in the green, blue, red and infrared close spectrum, after 12 months of plantation. Those images were obtained with two cameras S-VHS: one capable of capturing the bands of the visible spectrum (400 - 700 nm) and other capable of capturing the bands in the visible and near infrared band (400 - 1100 nm). In these cameras, subtraction filters were also used to separate the bands of the spectrum to work. Besides, with the use of the software ENVI, it was made an analysis of the values of pixels of each portion, being obtained the minimum, medium, maximum values and the mean standard deviation. Then, these values were compared to each other and put together according to the multivariate statistical analysis, looking for relationships between the data of the images and the treatments. Significant relationships between the tree and pixel values data were found for the images obtained in 1500 m high by the camera COHU, in the spectra blue and close infrared and for the camera PANASONIC, in the red band.
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12

Silva, Paulo Henrique Müller da. "Impactos das doses e do parcelamento da fertilização na produtividade, lixiviação e ciclagem de nutrientes em plantações de eucalipto". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-14022012-102542/.

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No Brasil, está ocorrendo a expansão da área florestal plantada com espécies do gênero Eucalyptus, sendo que a elevada produtividade pode ser atribuída às pesquisas e melhorias operacionais introduzidas nas ultimas décadas. Nos experimentos realizados em diferentes regiões do Brasil, tem se observado maior incremento dos eucaliptos com o aumento das doses de fertilizantes. Mas o excesso ou a aplicação inadequada de fertilizantes gera freqüentemente o desperdício dos insumos e a lixiviação dos elementos, que podem contaminar o solo e o lençol freático. Portanto, foi objetivo deste trabalho analisar o efeito de doses, bem como do parcelamento da aplicação de fertilizantes na produtividade e na ciclagem de nutrientes em plantios de eucaliptos, além de avaliar a lixiviação de nitrogênio e potássio no solo, após a fertilização de cobertura parcelada em comparação à aplicação em dose única, três meses após o plantio. O experimento foi implantado no município de Anhembi-SP, sendo constituído por cinco tratamentos com a aplicação de doses crescentes e eqüidistantes de N, P e K com a aplicação da fertilização de cobertura (N e K) em 4 parcelas e por um tratamento com fertilização de cobertura aplicada em dose única, três meses após o plantio. Foram avaliados o incremento volumétrico e a produção da biomassa aérea e radicular das árvores, as concentrações e os estoques de nutrientes nos eucaliptos (mineralomassas), a eficiência do uso dos nutrientes, a transferência de nutrientes das árvores para o solo através da produção de folhedo (ciclo biogeoquímico), a ciclagem interna dos nutrientes (ciclo bioquímico), bem como o fluxo de água e a lixiviação do N e K no solo nas profundidades de 20 e 90 cm. Os eucaliptos responderam positivamente ao aumento das doses de fertilizantes, principalmente na fase inicial, apresentando maior produtividade (altura, volume e biomassa). O tratamento com a maior dose obteve, aos 24 meses de idade, 105 t ha-1 de biomassa total, sendo 48% superior ao tratamento sem fertilização, com apenas 71 t ha-1. Entretanto o efeito das maiores doses de fertilizantes foi mais acentuado na fase inicial do crescimento, até os 12 meses de idade. Ocorreu a atenuação do incremento ao longo do tempo, sendo que aos 24 meses não foram observadas diferenças significativas entre os tratamentos com a aplicação de doses de fertilizantes. A fertilização também propiciou maior acúmulo de nutrientes (mineralomassa) nos componentes das árvores (folhas, galhos, lenho, casca e raízes) e maior transferência de nutrientes para o solo, através do folhedo. Assim, os eucaliptos com a adição das doses mais elevadas de fertilizantes devolveram ao solo, via folhedo, aproximadamente 50 kg ha-1 ano-1 de N, 20 kg ha-1 ano-1 de K e 80 kg ha-1 ano-1 de Ca, enquanto o tratamento sem fertilização transferiu para o solo apenas 25 kg ha-1 ano-1 de N, 6,5 kg ha-1 ano-1 de K e 47 kg ha-1 ano-1 de Ca, no período entre 12 a 24 meses de idade. Foi observado que os eucaliptos com menor disponibilidade de nutrientes foram mais eficientes no uso do N e K. Não foram observadas diferenças significativas na produção de biomassa lenhosa entre os tratamentos com aplicação da fertilização de cobertura de forma parcelada ou em dose única, sendo observado maior lixiviação do N e do K, aos 90 cm de profundidade, com a aplicação em dose única.
It is occurring, in Brazil, the expansion of planted forest area with species that belong to the Eucalyptus genus, one of the reasons is the high biomass productivity resulting from the research and the operational improvements that have been implemented during the last decades. In several field experiments, has been observed an increase of eucalypts growth by using a higher amount of fertilizers. But excessive or inappropriate application of fertilizers may generate the fertilizer waste and nutrients leaching that may contaminate soil and watertable. The objective of this study was to evaluate the effect of fertilization doses in the biomass production and nutrient cycling from the eucalypt plantation, as well as evaluating the N and K leaching in the soil after the application of split and single dose of N and K fertilization. The experiment was set up in the Anhembi city (State of São Paulo), and it was constituted by five treatments with doses of fertilizers and N and K in split application (4 times) and also a treatment with a single dose of N and K application, 3 months after planting. It was evaluated the wood volume, root and shoot biomass, concentrations and stocks of nutrients in eucalypts biomass (mineralomass), the efficiency of nutrient use, the nutrient transference from the canopy to the soil through litter production (leaf-fall), internal nutrients cycling (biochemical cycle), the water flow and leaching of N and K in the soil at the depths of 20 and 90 cm. The eucalypts responded positively to the increased fertilization doses, especially in the first year, with higher productivity (height, DBH and biomass). Treatment with the highest dose for 24 months produced 105 tons ha-1 of biomass, 48% higher than the treatment without fertilization, with only 71 tons ha-1. However the effect of higher doses was more evident at an early stage of tree growth, up to 12 months of age. However, the difference decrease over time, and at 24 months there were not significant differences among the treatments with fertilization application. Fertilization also resulted in higher nutrients accumulation (mineralomass) in all tree components (leaves, branches, wood, bark and roots) and increased nutrient transfer to the soil through deposition of leaf litter. Thus, the eucalypts applied the highest addition of fertilization dose returned to the soil through litter, about 50 kg ha-1 yr-1 of N, 20 kg ha-1 yr-1 of K and 80 kg ha-1 yr-1 of Ca, while the treatment without fertilization transferred to the soil only 25 kg ha-1 yr-1 of N, 6.5 kg ha-1 yr-1 of K and 47 kg ha-1 yr-1 of Ca during 12 months (between 12 to 24 months after planting). It was observed more efficient use of nutrients from the eucalypts with lower nutrients availability. Also, there were no significant differences in the growth of eucalypts from the treatments with split N and K application and single N and K application. However, there was a higher leaching of K and N, 90 cm deep, in the single application treatment.
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13

Timo, Thiago Philipe de Camargo e. "Mamíferos de médio e grande porte em áreas de cultivo de eucalipto das bacias do Alto Paranapanema e Médio Tietê, Estado de São Paulo". Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-17112009-081119/.

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A região compreendida entre os trechos alto do rio Paranapanema, médio do rio Tietê e o rio Sorocaba possui longo histórico de influência humana na paisagem. Esta influência intensificouse nos dois últimos séculos com a passagem de estradas de ferro e a construção de hidroelétricas, entre outras modificações que implicaram em alterações do uso da terra. Uma das mudanças significativas foi a chegada e expansão rápida da silvicultura de eucalipto. A estrutura desta vegetação cultivada e seu ciclo produtivo têm influência sobre as comunidades vegetais e animais nativas. Neste estudo foi avaliada a influência da conformação geométrica da paisagem e da idade de plantio de áreas de silvicultura de eucalipto sobre padrões de distribuição e abundância de mamíferos de médio e grande porte. Foi possível demonstrar que herbívoros são favorecidos por áreas extensas de vegetação nativa com geometria simples, enquanto onívoros se beneficiam da ausência de grandes predadores e da geometria convoluta da vegetação nativa em áreas onde a matriz de eucalipto domina a paisagem. Onde o eucalipto é a feição dominante da paisagem agrícola, estas espécies utilizam o interior dos talhões em fase intermediária de cultivo, quando existe sub-bosque que ofereça abrigo e recursos alimentares. Tais observações reforçam a importância da manutenção de Áreas de Preservação Permanente e de Reserva Legal em paisagens agrícolas, assim como questionam o conservadorismo na aplicação da legislação que leva ao embargo do corte de eucaliptais com sub-bosque, diminuindo o valor de conservação desta cultura sobre a fauna de médios e grandes mamíferos nativos. Palavras-chaves: mamíferos de médio e grande porte, padrões de distribuição e abundância, paisagem agrícola, eucalipto.
The region comprehended amid the high portion of river Paranapanema, mid portion of river Tietê and the river Sorocaba, has a long history of human influence on landscape. This influence was intensified during the past two centuries through the passage of railroads and hydroelectric dam constructions along with other modifications that had implications on land use changes. One of the significant modifications was the arrival and rapid expansion of eucalypt silviculture. The structure and cycle of production of this cultivated vegetation have influence on plant and animal native communities. In this study, geometric conformity and age of planted stands in eucalypt silviculture areas were evaluated on patterns of distribution and abundance of medium to large size mammals. It was possible to demonstrate that herbivores are favored by extensive areas of native vegetation, while omnivores benefit from the absence of large predators and complex geometry of native vegetation in landscapes with dominant eucalypt matrix. Where eucalypt plantations are the commonest landscape features, these species use central areas of silviculture stands in intermediate stages of cultivation, when there is undergrowth that offers shelter and food resources. These observations reinforce the importance of Permanent Preservation Areas and Legal Reserves in agricultural landscapes, as well as they question the conservatism on application of environmental laws that leads to the legal impediment of harvest on eucalypt stands with undergrowth, decreasing conservation value of this culture for medium to large size mammals fauna.
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14

Henry, Joseph Douglas. "Evapotranspiration in a catchment dominated by eucalypt forest and woodland". Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/12283.

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There is on-going need for reliable estimates of evapotranspiration (ET) at catchment scales to support objective decision-making for managing water supplies, and enhancing understanding of processes and modelling. Without reliable estimates of ET, water supply and catchment management agencies are exposed to significant economic, social and even environmental risks. This thesis focuses on identifying possible methodologies for estimating ET in a catchment dominated by eucalypt forest and woodland. More specifically, this thesis tests the hypothesis that different methods of deriving daily, catchment ET for a headwater in Australia meet underlying assumptions and yield similar results. The hypothesis was tested by using three approaches to estimate catchment ET: soil moisture changes (point scale), satellite imagery of leaf area index (MODIS, hillslope scale), and discharge (streamflow) and the storage-discharge relationship (catchment scale). Data from Corin Catchment, an unregulated catchment vital to the Australian Capital Territory and the surrounding region, is the basis of this study. After the General Introduction (Chapter 1), methods for estimating ET in eucalypt communities throughout Australia at various temporal and spatial scales are systematically reviewed (Chapter 2). Of the 1614 original research papers investigated, 52 were included for further investigation. A clear outcome is that transpiration by the overstorey, measured using sap flow, is the most frequently measured component of ET, and that physiological studies dominate estimates of ET. Very few studies were conducted at the catchment scale. Further, scaling ET from tree to catchment scales was rarely attempted, and the effect of scaling for water resource management is mostly unquantified and requires attention. The first method used to calculate catchment ET is based on up-scaling of soil moisture changes on the basis of a digital soil map (Chapter 4). The data presented here rejects the hypothesis that ET (derived from soil moisture) and overstorey transpiration (derived from sap flow) are well correlated. Instead, the data suggest that soil moisture-derived ET and overstorey transpiration obtained water from different sources. The key findings of this chapter are that this approach is not suitable for estimating ET at catchment scales because it is restricted to drier periods, and because trees did not solely rely on the defined root-zone for water supply. The second method to calculate catchment scale ET (Chapter 5) tests if hillslope-scale satellite imagery (MODIS leaf area index) can be up-scaled to estimate catchment ET. An outcome of this work is that caution is needed when using MODIS leaf area index for water resource planning in evergreen forests across the globe, particularly for forests with significant understorey and a relatively open overstorey canopy at some periods of the year. This method is deemed not suitable for estimating ET over the study area. The third method to calculate catchment scale ET (Chapter 6) is based on integrating discharge using a single non-linear equation to characterise the study area. This method yielded catchment ET far greater (18 times larger) than the largest observed measure of potential ET. As with the method based on soil moisture changes, it was restricted to drier periods. This method was clearly unsuitable for estimating ET over the study area due to relatively quick recession, large range in hourly discharge and significant scattered recession at low discharge. Overall, this thesis rejects the hypothesis that different methods of deriving daily, catchment ET for a headwater in Australia meet underlying assumptions and yield similar results. An important limitation identified through this research is the ability to determine a ‘correct’ estimate of catchment ET. Further research should focus on enhancing understanding of scaling ET within and beyond Australia, generating more daily catchment ET from up-scaled soil moisture changes, further evaluating ET from up-scaled satellite imagery, and identifying catchment characteristics to allow ET to be derived from discharge. Water resource managers must be diligent when selecting and applying a method to estimate catchment ET.
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15

Phiri, Darius. "Biomass modelling of selected drought tolerant Eucalypt species in South Africa". Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85739.

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Thesis (MScFor)--Stellenbosch University, 2013.
ENGLISH ABSTRACT: The study aims at developing models for predicting aboveground biomass for selected drought tolerant Eucalyptus (E) species (E. cladocalyx, E. gomphocephala and E. grandis x camaldulensis) from the dry west coast. Biomass models were fit for each of the species and a cross-species model was parameterised based on pooled data for all the three species. Data was based on destructive sampling of 28 eucalypt trees which were 20 years of age and additional five five-year old E. gomphocephala trees. Preliminary measurements on diameter at breast height (dbh), height (h) and crown height were recorded in the field. The sampled trees were then felled and samples of discs, branches and foliage were collected. Density of the wood discs and the bark was determined by a water displacement method and computer tomography scanning (CT-scanner). Stem biomass was reconstructed using Smalian’s formula for volume determination and the calculated densities. Upscaling of the crown was carried out by regression equations formulated by employing the sampled branches. Further assessment was carried out on a sub-sample by subjecting the samples to different drying temperatures in a series between 60 and 105ºC. Linear models were parameterised by a simultaneous regression approach based on Seemingly Unrelated Regression (SUR) using the “Systemfit” R statistical package. The predictor variables employed in the study were dbh, d2h and h in which the coefficient of determination (R2), Mean Standard Error (MSE) and Root Mean Standard Error (RMSE) were used to determine the goodness of fit for the models. Akaike Information Criteria (AIC) was also used in the selection of the best fitting model. A system of equations consisting of five models was formulated for each Eucalyptus species. The biomass prediction models had degrees of determination (R2) ranging from 0.65 to 0.98 in which dbh and d2h were the main predictor variable while h improved the model fit. The total biomass models were the best fitting models in most cases while foliage biomass had the least good fit when compared to other models. When the samples were subjected to different drying temperatures, stem wood had the largest percentage change of 6% when drying from 60ºC to 105ºC while foliage had the lowest percentage change of less than 2%.
AFRIKAANSE OPSOMMING: Die doel met hierdie studie is om modelle vir die voorspelling van die bogrondse biomassa van drie droogte-bestande Eucalyptus (E) spesies (E. cladocalyx, E. gomphocephala en E. grandis x camaldulensis), gekweek op die droë kusvlakte in Wes-Kaapland, te ontwikkel. Biomassa modelle vir elk van die spesies is gepas en ’n model gegrond op die gekombineerde data van al drie die spesies, is geparameteriseer. Verder is die biomassa variasie onder verskeie droogingstemperature vasgestel. Die data versameling is uitgevoer gegrond op die destruktiewe mostering van 28 Eucalyptus bome wat 20 jaar oud was en ’n bykomende vyf vyfjarige E. gomphocephala bome. Die aanvanklike mates, naamlik deursnee op borshoogte (dbh), boomhoogte (h) en kroonhoogte is in die veld opgemeet. Die gemonsterde bome is afgesaag en monsters van stamhout skywe, takke en die bas is versamel. Die digtheid van die skywe en die bas is deur die waterverplasing metode, en Rekenaar Tomografie skandering (“CT-scanning”) vasgestel. Stam biomassa is rekonstrukteer deur gebruik te maak van Smalian se formule vir die vasstelling van volume en berekende digtheid. Die opskaal van die kroon biomassa is gedoen met behulp van regressie vergelykings van gekose takmonsters. Submonsters is onderwerp aan ’n reeks van verskillende drogingstemperature tussen 60 en 105ºC. Lineêre modelle is deur ’n gelyktydige regressie benadering gegrond op die Seemingly Unrelated Regression (SUR) wat ’n“Systemfit” R statistiese pakket gebruik, parameteriseer. Die voorspeller veranderlikes wat in hierdie studie gebruik is, is dbh, d2h en h waarin die koëffisient van bepaling (R2), gemiddelde standaardfout (MSE) en vierkantswortel van die gemiddelde standaardfout (RMSE) gebruik is om vas te stel hoe goed die model pas. Akaike Inligting Kriteria is gebruik vir die seleksie van die gepaste model. ’n Reeks vergelykings wat bestaan uit vyf modelle is vir elke Eucalyptus spesie geformuleer. Die biomassa voorspelling model het waardes vir die koëffisiente van bepaling (R2) opgelewer wat strek van 0.65 to 0.98% en waarin dbh en d2h die hoof voorspelling veranderlikes is, terwyl h die pas van die model verbeter. Die totale biomassa model het in die meeste gevalle die beste gepas en die blaarbiomassa die swakste as dit met die ander modelle vergelyk word. Tydens droging vind die grootste persentasie verandering van 6% by stamhout plaas tussen temperature van 60ºC tot 105ºC, en die kleinste persentasie verandering van minder as 2% by blare.
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16

Correia, Joana Raquel de Aguiar Medeiros. "Toxicity of eucalypt and pine leaf extracts in fish and frogs". Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/11044.

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Mestrado em Biologia Aplicada
A desmatação de florestas naturais, aliada à crescente extensão de florestas plantadas, de monoculturas, como o eucalipto e o pinheiro, leva à perda de biodiversidade e tem outras consequências que são particularmente nefastas em ribeiros intermitentes, prejudicando os organismos aquáticos, como peixes e anfíbios. O presente estudo teve como principais objetivos: (i) avaliar as características físico-químicas de extratos aquosos de folhas de eucalipto e pinheiro produzidos em laboratório, e de amostras de água recolhidas em poças de rios intermitentes localizados em florestas de eucalipto, pinheiro e caducas nativas; (ii) avaliar a toxicidade dos extratos de eucalipto e pinheiro em três espéciesmodelo, peixe-zebra (Danio rerio), rã-verde (Pelophylax perezi) e rã-de-unhasafricana (Xenopus laevis), e comparar a sensibilidade das espécies usadas aos diferentes extratos, tendo em conta a mortalidade e as malformações; (iii) avaliar os efeitos sub-letais dos extratos aquosos de eucalipto e pinheiro no peixe-zebra, com recurso aos biomarcadores vitelogenina (vtg), catalase (CAT), glutationa S-transferase (GST) e colinesterase (ChE). No geral, os extratos de folhas de eucalipto e pinheiro reduziram oxigénio e pH, e aumentaram fenóis, terpenos, lípidos e condutividade. O extrato de eucalipto mostrou ser mais tóxico do que o de pinheiro, para P. perezi e D. rerio, enquanto para X. laevis a toxicidade dos extractos é semelhante. A sensibilidade dos embriões aos extratos de eucalipto foi: D. rerio > X. laevis P perezi; e para o de pinheiro: X. laevis > D. rerio P. perezi. As malformações mais observadas foram cauda torcida e edemas. Os extratos aquosos de eucalipto e pinheiro induziram efeitos teratogénicos nos embriões do X. laevis. A actividade da CAT diminuiu em ambas as exposições (eucalipto e pinheiro), enquanto a GST diminuiu quando os organismos foram expostos ao extrato de eucalipto, mas aumentou quando expostos ao extrato de pinheiro. Não se verificaram diferenças significativas na vtg e na ChE com nenhum dos extratos. Os resultados obtidos sugerem que os extratos de folhas de eucalipto e pinheiro têm efeitos, sobre o peixe-zebra, ao nível do stress oxidativo, mas não parecem ter acção anti-colinérgica ou de disrupção endócrina. Com base nos efeitos tóxicos causados a embriões de peixes e anfíbios, obtidos neste estudo, por exposição dos mesmos a concentrações de extratos aquosos de folhas de eucalipto e pinheiro, que poderão ser encontradas no contexto real, afirmam-se os efeitos deletérios que os lixiviados das florestas plantadas de eucalipto e pinheiro podem ter nos estágios de vida primários das espécies aquáticas.
Deforestation of natural forests allied to the increasing extent of monoculture plantation forests, such as eucalypt and pine, causes biodiversity loss and has other consequences that are particularly damaging in intermittent streams, harming aquatic organisms, like fishes and amphibians. The present study aimed to: (i) assess the physico-chemical characteristics of laboratory aqueous extracts of eucalypt and pine leafs, and of intermittent stream summer pools draining eucalypt, pine or broadleaf forests; (ii) evaluate the toxicity of leaf extracts of pine and eucalypt in the embryos of three model species, the Zebrafish Danio rerio, the Perez’s frog Pelophylax. perezi and the African clawed frog Xenopus laevis, and compare the sensitivity of the studied species to the different leaf extracts using malformations and mortality as main endpoints; (iii) assess the sub-lethal effects of eucalypt and pine leaf aqueous extracts in zebrafish embryos, using the biomarkers vitellogenin (vtg), catalase (CAT) glutathione S-transferase (GST) and cholinesterase (ChE) as main endpoints. In general, leaf extracts were found to reduce water oxygen and pH, and increase dissolved phenolics, terpenes, lipids and conductivity. The eucalypt leaf extracts were more toxic than pine extracts for P. perezi and D. rerio embryos. Whereas for X. laevis the toxicity of these extracts seems to be similar. The sensitivity of the embryos to the eucalypt extracts was: D. rerio > X. laevis P. perezi; and to the pine extracts: X. laevis > D. rerio P. perezi. The malformations most commonly observed were tail curvation and edemas. We observed that exposure to eucalypt and pine leaf extracts induced teratogenicity in X. laevis embryos. CAT activity decreased for the eucalypt and pine leaf extracts. GST activity decreased in organisms exposed to the eucalypt leaf extract and increased for the pine. There were no significant differences in vtg nor in ChE for any of the extracts tested. These results suggest that eucalypt and pine leaf aqueous extracts affect the zebrafish embryos causing oxidative stress, but do not seem to have anti-cholinergic action nor to cause endocrine disruption. Based on the toxic effects to fish and amphibian embryos, obtained in this study, by exposing them to concentrations of eucalypt and pine leaf aqueous extracts, which can be found in the real context, the harmful effects that eucalypt and pine plantation forest leachates might have on the aquatic species early life stages are affirmed.
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17

Hodecker, Bárbara Elias Reis. "Comparison of drought stress responses of tolerant and sensitive eucalypt genotypes". Universidade Federal de Viçosa, 2015. http://www.locus.ufv.br/handle/123456789/6511.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Para lidar com a restrição hídrica, seleções de genótipos tolerantes à seca tem sido umas das principais estratégias adotadas nos novos plantios. Entretanto, no Brasil, a maioria das seleções genéticas tem focado principalmente nas taxa de crescimento e produtividade das fibras, sem levar em consideração o melhor entendimento das respostas morfológicas e bioquímicas em resposta ao déficit hídrico e também a influência dos nutrientes nestes processos. Assim, os principais objetivos foram comparar as respostas de clones tolerantes e sensíveis de eucalipto frente ao déficit hídrico a fim de auxiliar no entendimento destas características e futuras seleções genéticas para esta espécie. Outro objetivo visou identificar a importância da fertilização com B (boro) nos mecanismos adaptativos relacionados à tolerância à seca e o melhor entendimento das relações envolvendo a eficiência nutricional em diferentes materiais genéticos e sua influência na seleção de genótipos tolerantes, utilizando para este fim, os diagramas nutricionais. Para atingir estes objetivos, foram conduzidos quatro experimentos, sendo três deles em casa de vegetação e um em condições de campo. O objetivo do primeiro experimento foi avaliar a influência da nutrição com boro em processos relacionados à eficiência do uso da água em seis espécies de eucalipto oriundas de diferentes condições edafoclimáticas e submetidas à seca. O segundo experimento foi destinado à identificação das alterações morfológicas, fisiológicas e moleculares causadas após longo período de restrição hídrica, em quatro espécies de eucalipto em condições de campo. O objetivo do terceiro experimento foi avaliar as variáveis capazes de discriminar clones com tolerância diferencial ao estresse hídrico e fornecer marcadores para plantas jovens de eucalipto. O quarto experimento objetivou avaliar o comportamento diferencial no crescimento inicial e eficiência nutricional e da água em dez clones de eucaliptos submetidos à restrição hídrica. No primeiro capítulo, observamos elevado incremento na eficiência do uso da água em plantas sob seca e suplementadas com B, devido à combinação de alta taxa fotossintética, alta concentração de K+ em folhas, promovendo maior fechamento estomático, menor perda de água e maior translocação de açúcares para o crescimento radicular. No experimento de campo (capítulo 2), os resultados obtidos sugerem que árvores de eucalipto crescendo sob uniforme e elevada precipitação anual mostraram se mais estressadas após longo período de déficit hídrico, comparado às árvores submetidas à períodos de estresse hídricos recorrentes. No capítulo 3, não foi possível identificar uma variável capaz de discriminar e agrupar clones de eucalipto com tolerância diferencial ao estresse hídrico, no entanto, a interação entre eficiência do uso da água, ABA, fotossíntese, transpiração e razão massa de matéria seca parte área e massa de matéria seca radicular mostraram ser importantes diferenças entre materiais genéticos. De maneira interessante, os resultados obtidos nos capítulo 4, mostram que sob estresse hídrico, clones tolerantes geralmente apresentam maior eficiência de absorção (AE), mas menor eficiência de uso (UE) de nutrientes, enquanto, clones sensíveis tiveram baixa AE, baixa UE para formação de raízes e alta AE para formação de folhas.
To cope with water restriction, the selection of drought tolerant genotypes has been the main strategy being adopted to establish new plantings. However, in Brazil, most genetic selections have focused mainly on growth rates and fiber productivity, without a clear understanding of morphological and biochemical responses of trees to water stress and the influence of nutrients on these processes. Thus, the main goals of this thesis were to compare water stress responses of tolerant and sensitive Eucalyptus genotypes in order to help to understand of Eucalyptus drought tolerance traits and assist future Eucalyptus breeding programs. Another objective was to identify the nutritional influence of B (boron) on water stress adaptive mechanisms and understand the relationship between nutritional efficiency and its influence on tolerant genotype selections using nutritional diagrams. In order to achieve these proposals, we conducted four experiments, three under controlled conditions and one under field conditions. The objective of the first experiment was to evaluate the influence of B nutrition on physiological processes related to water use efficiency in six Eucalyptus species of contrasting ecotypes under water stress. The second experiment was designed to identify the morphological, physiological and molecular changes caused by long periods of water restriction in four Eucalyptus clones under field conditions. The objective of the third experiment was to identify variables able to discriminate and group clones with differential tolerance to water stress and provide markers for young plants of eucalypt. The fourth experiment aimed to evaluate the differential behavior in the initial growth, biomass accumulation, and nutritional efficiency and water use in 10 Eucalyptus clones submitted to water stress. In the first chapter, we observed a strong increment on instantaneous WUE (water use efficiency) in D+B (drought and B supply) plants, due to the combination of higher photosynthetic rate, higher K+ concentration in leaves promoting higher stomatal closure, lower water loss and a higher translocation of sugars and B to root growth. In our field experiment (chapter 2), our results suggest that trees growing in the area with uniform annual high precipitation showed were stressed after a long period of drought, compared to those stands submitted to annual water-stress fluctuation period. In the chapter 3, we could not identify one single variable able to discriminate and group clones with differential tolerance to water stress, however, the interaction between WUEg (water use efficiency), ABA, A (photosynthesis), E (transpiration) and SDM/RDM (shoot dry matter/root dry matter) seemed to be the most important differences between clones under water stress. Our results from chapter 4, interestingly showed us that under water stress the drought-tolerant clone generally had high AE (absorption efficiency), but low nutrient UE (use efficiency), whereas the sensitive clone had low AE, low UE for root formation and high AE for leaf formation.
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18

Wilson, Michael. "Organic matter dynamics in willow and eucalypt lined central Victorian streams". Thesis, The Author [Mt. Helen, Vic.] :, 2001. http://researchonline.federation.edu.au/vital/access/HandleResolver/1959.17/69168.

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The spread of exotic willows (Salix spp.) in SE Australia, New Zealand and South Africa has provoked widespread debate in scientific, management and broader communities. In Australia, the extent of spread is unknown, but at least 30000 km of river frontage in Victoria are lined by willows. Management and research literature has identified the poor knowledge of willow impacts on Southern Hemisphere aquatic ecosystems. It has been speculated that the major distinction between deciduous willows and evergreen native vegetation will be the timing and quality of litterfall. This would have flow-on consequences for metabolic processes, stream biota and water quality at reach, stream and catchment scales. These two vegetation types were studied through the preparation of partial organic matter budgets for native and willow lined reaches in a central Victorian catchment. Organic matter inputs from litter, groundwater and gross primary production (GPP), organic matter standing crop . and respiratory output were quantified. Total inputs to willow and native reaches were similar (735 and 764 g ash free dry weight m•' yl, respectively). Inputs were dominated by litterfall (-60%) and there were no significant differences in annual litterfall between sites. GPP contributed -20% of total inputs and estimates suggested there were few significant differences in annual GPP, 24 h community respiration, ratio of GPP to community respiration (PIR) or net daily metabolism (NDM) between sites. Groundwater contributed -20% of total inputs with one third of the dissolved organic matter sourced during short flow paths through riparian sediments. Aggradation at willow sites appeared to increase the riparian flow path. Willow and native sites were heterotrophic and similarly dependent on allochthonous organic matter (P/R=O.2, NDM= -.6, and ratio of net primary production to total inputs -0.1). Willow research and management should also focus on retention capacity, including the recruitment and role of LWD and the structure and function of root systems. Removal of willows potentially facilitates native vegetation establishment but simultaneously decreases retention capacity and metabolic control by the canopy. Establishing native vegetation to fulfil broader biodiversity objectives whilst retaining willows for their potentially positive roles is a management challenge. In principle, establishing native species on the upland-sides of fringing willows and under willow canopies will direct succession toward a preferred outcome without destructive disturbance. Understanding of when benefits of willows outweigh their costs is a notable gap.
School of Science & Engineering
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19

De, Remy De Courcelles Vivien. "Studies of soil respiration in eucalypt forests of south east Australia". Thesis, The University of Sydney, 2014. http://hdl.handle.net/2123/10422.

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This thesis addresses gaps in knowledge of soil respiration in forests of south-east Australia. Soil respiration plays a major part in the cycle of carbon between soils - the biggest pool of terrestrial carbon - and the atmosphere. Despite its global significance, we have only a limited understanding of the magnitude and responses of soil respiration, and especially of its components, to abiotic (temperature, moisture, soil fertility) and biotic (photosynthesis, seasonality of belowground C allocation patterns and root growth, quality and quantity of above and belowground litter) controls. Furthermore, vegetation type may modulate the influences of these abiotic and biotic controls and with soil respiration research having been based mostly in the northern hemisphere, it is crucial that regional studies be conducted further afield. This thesis also considers the context of the current increase in atmospheric [CO2] and resulting predicted climate change that will directly or indirectly impact on soil respiration through extreme weather events, changes in the frequency and intensity of fires or increase in growth. Using both field and laboratory based techniques I measured respiration from soils supporting a variety of Eucalypts. Elevated atmospheric [CO2] did not have an effect on rates of soil respiration in a Eucalyptus saligna plantation, contrary to usual findings. Drought on the other hand slowed rates of respiration, owing to a slowing of the transfer of photosynthates from leaves to roots. The impact of an increase in above-ground litter deposition, a possible consequence of extreme weather events, or continuous increase in primary production can be subdued by the nature and quality of the litter in Eucalyptus pauciflora woodlands. No effect was recorded in the field but ground litter added to soils in the laboratory triggered a response including a priming effect. Root priming effect was also found to increase basal heterotrophic respiration by 54% on average in Eucalyptus regnans. The study on the contribution of roots to total soil respiration showed that it is necessary to use hybrid techniques to separate and estimates the contribution of components of soil respiration; in this thesis’ case the use of collars and chambers in the field and respirometer in the laboratory was determinant in identifying root priming effect. Great spatial variation in respiration rates was measured both in the simple ecosystem of a Eucalyptus saligna plantation and as a result of fire disturbance at the Messmate 1 site supporting Eucalyptus obliqua and Eucalyptus radiata. Finally, a synthesis of the results of the whole thesis considered the effect of soil temperature on soil respiration and showed that contrary to what is commonly agreed by the Q10 model, respiration rates reached a plateau for temperatures between 16°C to 23°C.
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20

Sutherland, Elizabeth F. (Elizabeth Fyfe). "Fire, resource limitation and small mammal populations in coastal eucalypt forest". Thesis, School of Biological Sciences, 1999. http://hdl.handle.net/2123/5344.

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Winckler, Daniela Cristina Firmino [UNESP]. "Bioecologia e controle microbiano de sarsina violascens (Herrich-schaeffer, 1856) (Lepidoptera: Lymantriidae) em Eucalyptus spp". Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/105380.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
A espécie Sarsina violascens (Herrich–Schaeffer, 1856) (Lepidoptera: Lymantriidae) é relatada como praga primária em plantios de eucalipto e teve sua primeira ocorrência registrada em 1975. No período de 2006 a 2009 houve grandes surtos dessa praga, causando desfolhamento intenso em plantios de eucalipto no norte da Bahia. Apesar dos estudos feitos no passado terem considerado espécies de eucalipto, há pouca informação sobre a suscetibilidade de clones híbridos de eucalipto à mariposa violácea. O presente trabalho teve por objetivo avaliar a biologia de S. violascens em diferentes espécies e híbridos de eucalipto e em diferentes temperaturas, além de avaliar a eficiência de entomopatógenos no controle de S. violascens. No experimento 1 a biologia de S. violascens foi determinada nas espécies Eucalyptus grandis, E. urophylla e dois híbridos de E. grandis x E. urophylla (‘urograndis’). Os parâmetros avaliados foram duração e viabilidade dos estágios larval, pupal, adulto e de ovo e do ciclo total. No experimento 2 foi selecionada a espécie E. urophylla como padrão e avaliou-se o efeito de diferentes temperaturas (18, 22, 26 e 30oC) no desenvolvimento de S. violascens, avaliando-se os mesmos parâmetros anteriores. Os resultados obtidos no experimento 1 revelaram que E. urophylla ofereceu melhores condições para odesenvolvimento de S. violascens, com maior viabilidade larval (85,3 %), pupal (78,7 %) e de ovos (72,6 %), e menor duração do ciclo total (54,4 dias). A espécie E. grandis foi considerada a menos adequada ao desenvolvimento de S. violascens, revelando baixas viabilidades larval (29,2 %) e pupal (28,9 %). Os resultados obtidos com os dois híbridos foram intermediários comparativamente com as espécies testadas. No experimento 2 as temperaturas de 18, 22 e 26°C foram adequadas para o desenvolvimento e reprodução de S. violascens, com alta viabilidade...
Defoliator lepidopterous are one of the main Eucalyptus pest groups in Brazil. There are records of caterpillars outbreaks since 1940, with important occurrences during 1980’s to 1990’s. The species Sarsina violascens (Herrich–Schaeffer, 1856) (Lepidoptera: Lymantriidae), named as violet moth, is related as pest in eucalypts plantations since 1975 and during 2006 to 2009, this species has occurred in outbreaks, causing intense defoliation in eucalypt plantations in Northern Bahia, Brazil. Despite studies in the past have considered species of eucalyptus, there is little information about susceptibility of Eucalyptus hybrid clones to violet moth. This study aimed to determine the biology of S. violascens in different species and hybrids of eucalyptus and in different temperatures. The insects were observed diary to evaluate life cycle in different species of eucalyptus (experiment 1) and in different temperatures (experiment 2). In experiment 1 were tested the following species: Eucalyptus grandis, E. urophylla and two hybrids of E. grandis x E. urophylla (‘urograndis’). The parameters evaluated were: duration and viability of larvae, pupae, adult and eggs phases and total life cycle. In experiment 2 was chose the species E. urophylla as standard and evaluated the effect of temperatures of 18, 22, 26 and 30oC, considering the same previous parameters. The results obtained in experiment 1 showed that E. urophylla offered better conditions to S. violascens development and reproduction, due the higher larvae, pupae and eggs viability, and shorter total life cycle duration. The species E. grandis was considered as less adequate to S. violascens development and reproduction, with low larvae and pupae viability. To the two hybrid clones, the results were intermediary comparatively with tested species. In experiment 2 temperature of 18°C showed the most adequate to S. violascens... (Complete abstract click electronic access below)
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22

Mosca, Andreia Arruda de Oliveira. "Avaliação dos impactos ambientais de plantações de eucalipto no Cerrado com base na análise comparativa do ciclo hidrológico e da sustentabilidade da paisagem em duas bacias de segunda ordem". Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/8/8135/tde-19122008-095822/.

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Considerando as polêmicas geradas em torno dos possíveis impactos ambientais negativos causados pelo eucalipto fora de seu ambiente de origem (Austrália), as discussões aqui apresentadas também perpassam uma das manifestações da crise sócioeconômica verificada no final do século XX, que é a questão ambiental, pois aborda três temas globais fundamentais e desafiadores, neste início de século para a manutenção da vida, consequentemente, das atuais e futuras gerações: a monocultura, o aumento no consumo de água, e a exploração mineral. Partindo-se dos princípios teóricometodológicos apoiados na Teoria Geral de Sistemas, no monitoramento hidrológico de duas sub-bacias pareadas e na cartografação da fragilidade ambiental, buscou-se compreender os mecanismos relacionados a sustentabilidade da paisagem associada a plantações de eucalipto localizadas no cerrado do sudeste goiano. Os resultados do monitoramento da vazão mostram valores médios mais elevados para a sub-bacia com eucalipto, associada a uma hidrográfa mais rápida e concentrada, embora sua subida seja retardada por conta da interceptação das copas. A análise da qualidade da água do deflúvio apresentou-se ligeiramente superior para a sub-bacia com cerrado, sendo os macroinvertebrados bentônicos expressivos das alterações ambientais processadas. O monitoramento do nível estático nos poços piezométricos instalados nas sub-bacias mostrou-se fundamental para a compreensão dos fatores associados ao secamento da nascente com eucalipto. A integração dos mapas temáticos para a análise da fragilidade da paisagem associada ao mapa da Área Variável de Afluência revelou-se bastante aplicável ao manejo florestal sustentável por oferecer subsídios ao planejamento, quando aliados a indicadores consistentes. Espera-se que as sugestões propostas e os resultados apresentados venham agregar subsídios técnico-científicos para que os tomadores de decisão, as comunidades locais e os diversos atores sociais envolvidos sejam estimulados a compreender, refletir e agir.
The present study aims to contribute to the analysis of the environmental impact of eucalypt plantations in the Cerrado region of the southern part of the State of Goiás, Brazil. The analysis were based on the methodology of the General Theory of the Systems and also on the results of hydrologic monitoring of two experimental catchments, which included groundwater monitoring, and the cartographic analysis of the environmental fragility. The monitoring results show higher average values of streamflow for the eucalypt catchment, associated with a more rapid and concentrated stormflow response, even though the beginning of the rising limb was delayed, probably due to the rainfall interception by the eucalypt canopy. Based on the analyzed water quality parameters, it can be concluded that the Cerrado catchment presented slightly better values, which were confirmed by the comparativy analysis of the benthonic macroinvertebrates. The inclusion of the identification of the riparian areas of the catchments as one of the thematic maps of the integrated analysis of the landscape fragility revealed to be very pertinent for the planning of the sustainable management of forest plantations and for the correct evaluation of the associated environmental impacts.
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23

Silva, André Luiz Pinheiro da. "Custo de produção, colheita e transporte de madeira de eucalipto proveniente do programa produtor florestal no sul do Espírito Santo". Universidade Federal do Espírito Santo, 2012. http://repositorio.ufes.br/handle/10/5777.

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Com a finalidade de analisar a atividade de produção de madeira proveniente do Programa Produtor Florestal como alternativa econômica de investimento, foram coletados dados de custos de implantação de povoamentos de eucalipto, bem como os custos referentes à colheita e ao transporte. Os dados referentes às atividades e os respectivos custos das fases compreendidas na produção, além dos preços pagos por metro cúbico de madeira no ano de 2011, foram obtidos junto à empresa Fibria S.A., fomentadora de projetos. Os dados dos custos de colheita e transporte foram obtidos por meio de aplicação de questionários em seis propriedades em fase de colheita nos municípios de Alegre, Divino de São Lourenço e Jerônimo Monteiro, no estado do Espírito Santo. Foram obtidos dados de área plantada, custo das fases compreendidas no processo de colheita e no processo de transporte da área de produção até o pátio de estocagem de madeira da Fibria S.A., localizado no município de Cachoeiro de Itapemirim, ES, além da produtividade média por hectare e o preço médio pago pelo metro cúbico de madeira de eucalipto proveniente do Programa Produtor Florestal no ano de 2011. A avaliação dos dados compreendeu na análise, separadamente, dos custos referentes ao processo de produção, colheita e transporte e sua participação no custo total da atividade, e o cálculo dos índices econômicos da atividade. Os custos com maior participação no processo de produção foram custo da terra (34,92%), implantação (23,33%), transporte (21,09%) e colheita (20,65%). Ao preço da madeira do fomento praticado pela empresa, o investimento em reflorestamento, de acordo com os índices econômicos calculados, mostrou-se como uma alternativa viável economicamente, aos produtores
With the purpose of analyze the activity of production of wood originating the Forestry Partners Program an economical alternative as investment, Data was gathered about establishment costs of eucalyptus, as well as costs relating to harvesting and transportation. Data referring the activities and the respective costs of all stages in the production comprehended, besides the price paid per cubic meter of wood in the year 2011 were obtained from the company Fibria SA, promoter of projects. The cost data harvesting and transportation were obtained by means of application of questionnaires in six properties in harvesting stage in the municipalities of Alegre, Divino de São Lourenço and Jerônimo Monteiro in Espírito Santo state. They obtained the data from planted area, cost of phases comprehended in the process of harvesting and transportation process in the production area to the storage yard timber Fibria SA, located in the municipality of ES, Cachoeiro de Itapemirim, beyond the average productivity per hectare and the average price paid by the cubic meter of eucalyptus wood coming from Forestry Partners Program in 2011.The evaluation of consisted in analyzing separately the costs concerning to the production process, harvest and transport and its share in the total cost of the activity, and calculation of indices of economic activity. The costs with greater participation in the production process were opportunity cost of land (34,92%), implantation (23,33%), transportation (21,09%) and harvest (20,65%). To the timber prices practiced by the fomentation company, investment in reforestation, according to economic indices calculated was economically viable alternative to producers
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24

Goodwin, Nicholas R. School of Biological Earth &amp Environmental Sciences UNSW. "Assessing understorey structural characteristics in eucalypt forests: an investigation of LiDAR techniques". Awarded by:University of New South Wales. School of Biological, Earth and Environmental Sciences, 2006. http://handle.unsw.edu.au/1959.4/28365.

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The potential of airborne LiDAR technology to quantify forest structure within eucalypt forests has been evaluated with a focus on the understorey stratum. To achieve this, three studies have been undertaken using multiple (4) LiDAR datasets acquired over three test areas located in Wedding Bells State Forest, Coffs Harbour, Australia. Initially, the effects of sensor configuration were evaluated using field measurements collected from three structurally and topographically differing field plots (40 x 90 m areas). Results indicated that canopy height profiles derived from LiDAR data at the plot scale were largely unaffected by a change in platform altitude from 1000 to 3000 m (p > 0.05). In addition, the derivation of individual tree attributes was found to be highly sensitive to the density of LiDAR observations whilst higher platform altitudes showed an increased proportion of single returns over forested areas. In the second study, an innovative field based approach was developed to sample the structure of the understorey (horizontally and vertically) for LiDAR validation purposes. Using two separate LiDAR datasets, this research confirmed that mean understorey height and understorey cover can be effectively mapped in areas of low to medium canopy cover whilst no significant relationship (p > 0.05) was identified between field and LiDAR estimates of maximum understorey height. In the third study, an optimised LiDAR beam interception model was developed and validated, and then applied to assess the interaction of extrinsic and intrinsic factors of the LiDAR survey. This demonstrated that the probability of beam interception through the forest canopy can be affected by factors both intrinsic (e.g. crown cover) and extrinsic (e.g. scan angle) to the structure of the canopy. Overall, the results of this research indicate that optimising the sensor configuration is important to the derivation of particular forest structural attributes and significantly, there is potential for LiDAR technology to provide quantitative and spatially detailed estimates of key understorey attributes such as mean height and cover.
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25

Cadete, Sonia Marisa Silva. "Enzymatic upgrading of eucalypt paper-grade kraft pulp within dissolving pulp production". Master's thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/16089.

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Mestrado em Biotecnologia - Biotecnologia Industrial e Ambiental
Dissolving-grade pulps are commonly used for the production of cellulose derivatives and regenerated cellulose. High cellulose content, low content of non-cellulosic material, high brightness, a uniform molecular weight distribution and high cellulose reactivity are the key features that determine the quality of a dissolving pulp. The first part of this work was an optimization study regarding the application of selected enzymes in different stages of a new purification process recently developed in Novozymes for purifying an eucalypt Kraft pulp into dissolving pulp, as an alternative to the pre-hydrolysis kraft (PHK) process. In addition, a viscosity reduction was achieved by cellulase (endoglucanase) treatment in the beginning of the sequence, while the GH11 and GH10 xylanases contributed to boost the brightness of the final pulp. The second part of the work aimed at exploring different auxiliary enzyme activities together with a key xylanase towards further removal of recalcitrant hemicelluloses from a partially bleached Eucalypt Kraft pulp. The resistant fraction (ca. 6% xylan in pulp) was not hydrolysable by the different combinations of enzymes tested. Production of a dissolving pulp was successful when using a cold caustic extraction (CCE) stage in the end of the sequence O-X-DHCE-X-HCE-D-CCE. The application of enzymes improved process efficiency. The main requirements for the production of a dissolving pulp (suitable for viscose making) were fulfilled: 2,7% residual xylan, 92,4% of brightness, a viscosity within the values of a commercial dissolving pulp and increased reactivity.
Pastas solúveis são normalmente usadas para a produção de derivativos de celulose e celulose regenerada. Alguns dos parâmetros que determinam a qualidade de uma pasta solúvel são: um elevado teor de celulose, baixo teor de material nãocelulósico, elevada brancura, uma distribuição uniforme de pesos moleculares e elevada reactividade da celulose. Na primeira parte deste trabalho, fez-se um estudo de optimização aplicando enzimas, previamente seleccionadas, em diferentes fases de um novo processo de purificação desenvolvido na Novozymes da pasta de eucalipto Kraft em celulose solúvel, como uma alternativa ao processo convencional de pré-hidrólise kraft. Além da purificação, a aplicação de celulases (endoglucanase) no início da sequência possibilitou uma diminuição da viscosidade, enquanto que a aplicação de xilanases das famílias GH11 e GH10 contribuíram também para o aumento da brancura da pasta final. A segunda parte deste trabalho teve como objectivo explorar várias actividades enzimáticas auxiliares conjuntamente com a melhor GH11 xilanase identifcada, de modo a promover a remoção das hemiceluloses mais recalciterantes de uma pasta Kraft de Eucalipto parcialmente branqueada. Todas as combinações das enzimas testadas resultaram numa fracção resistente de xilana residual (ca. 6% na pasta) que não foi possível hidrolisar. A produção de uma pasta solúvel foi possível usando um estágio de extracção alkalino a frio (CCE) no fim de uma sequência composta pelos seguintes estágios: O-X-D-HCE-X-HCE-D-CCE. A aplicação de enzimas melhorou a eficiencia do processo. Com esta sequência,os principais requisitos para a produção de uma pasta solúvel (adequada para producao de viscose) foram cumpridos: 2,7% de xilana residual, 92,4% de brancura, uma viscosidade dentro dos valores de uma pasta solúvel comercial e elevada reactividade.
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26

Blakemore, Philip Alexander. "Optimisation of steam reconditioning for regrowth-ash and plantation-grown eucalypt species". Connect to full text, 2008. http://ses.library.usyd.edu.au/handle/2123/2343.

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Thesis (Ph. D.)--University of Sydney, 2008.
Includes graphs and tables. Includes list of publications: p. iv. Title from title screen (viewed May 5, 2008). Thesis submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Chemical and Biomolecular Engineering. Includes bibliographical references. Also available in print form.
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27

Burgar, Joanna. "Bat habitat use of restored jarrah eucalypt forests in south-western Australia". Thesis, Burgar, Joanna (2014) Bat habitat use of restored jarrah eucalypt forests in south-western Australia. PhD thesis, Murdoch University, 2014. https://researchrepository.murdoch.edu.au/id/eprint/24229/.

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Restoration is an important tool in conserving biodiversity, yet passive faunal recolonisation may take decades, or longer, to occur. This is of particular conservation importance in biodiversity hotspots, such as south@western Australia, which are experiencing increasing fragmentation and rapidly drying climates. Within this hotspot, I investigated the response of nine insectivorous tree@dwelling bat species to restored mine@pits in jarrah (Eucalyptus marginata) forests. I assessed bat activity in restored, relative to unmined, forests and the suitability of restoration as foraging and roosting habitat. Bat echolocation call surveys measured bat activity in varying ages of restoration and unmined forest across two years (2010@2012) during both maternity and mating seasons. Although all bat species were detected in both forest types, restored mine@pits of all ages had significantly different bat communities and lower overall activity compared to unmined forest. Habitat filters to bat use of restoration were evident for the more manoeuvrable bat species and were predominantly related to midstorey forest structure. Tree density was the most important predictor of bat use of restoration for less manoeuvrable bat species. To determine the suitability of restored forest as foraging habitat I investigated the diet of three species (Chalinolobus gouldii, Nyctophilus gouldi and Vespadelus regulus) over maternity and mating seasons (2010/2011) by examining prey remains in faecal samples. I used high@throughput sequencing and bioinformatics analyses to phylogenetically group prey DNA and found that niche partitioning occurred, with dietary divergence positively related to bat ecomorphological divergence. In addition, I assessed the foraging potential of restored forest and found that prey occurrence did not necessarily equate to prey accessibility for all bat species. There was a synergistic effect of vegetation structure and insect biomass for edge foraging bat species. To determine the suitability of restoration as roosting habitat I used telemetry to radio@track 36 bats from two species (N. gouldi and V. regulus) to 59 distinct roosts. Not one bat was found roosting in restored forest and individuals preferred roosting in mature, tall trees in intermediate to late stages of decay. My research clearly shows that restored forest does not yet provide suitable foraging or roosting habitat for all jarrah forest bats. Improving habitat suitability through management manipulations, such as thinning and burning, may accelerate bat recolonisation of restored forest. In the interim, retention of mature forest patches is necessary for conserving and maintaining bat populations across restored landscapes.
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28

Blakemore, Philip. "Optimisation of steam reconditioning for regrowth-ash and plantation-grown eucalypt species". Thesis, The University of Sydney, 2008. http://hdl.handle.net/2123/2343.

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Steam reconditioning to recover collapse, in mid to low density eucalypt species, has been known for over ninety years. The current industrial practices for steam reconditioning have largely been based on a few older studies, which were often poorly documented and based on very small sample sizes. On top of this, many local practices and ‘rules of thumb’ have developed over time, many of which have a questionable scientific basis. This thesis was undertaken to more rigorously investigate and fundamentally understand collapse recovery, and try to optimise its application. The most obvious variable that kiln operators have control over is the moisture content of the timber prior to steam reconditioning. Experiments were undertaken to generate a range of moisture gradients (ranging from minimal to more industrially realistic) to evaluate the effect of moisture content on collapse recovery. An optimal moisture content for the core of the boards was found to be between about 18–20%, although there was no statistical difference in recoveries between about 17–25% moisture content. Below 15% moisture content recovery dropped off severely and intra-ring internal checking closure was incomplete, while at 25% moisture content an increased level of normal shrinkage, due to the early removal of drying stresses, was the main drawback. Above a core moisture content of about 35% incomplete closure of intra-ring internal checks was again observed. There was little evidence of re-collapse occurring in these high moisture content samples. Previously established relationships between density and collapse and drying rate were again generally observed in these experiments. However, for the first time an effect of collapse in reducing the fitted drying diffusion coefficients was also observed. It was also observed that, provided the moisture content of the board was in the critical range, most of the collapse recovery was achieved in the time it took to get the core of the board up to the steaming temperature of close to 100°C. This suggests that for most thicknesses a conservative reconditioning period of two hours at temperature is all that is required. This recommended shortening of the reconditioning cycle could dramatically increase the throughput of timber through the steam reconditioning chambers. Alternatively, it could mean that where modern final drying kilns are being used, the reconditioning treatment could be carried out within the final drying kiln. A finite element model was developed to demonstrate the mechanism by which collapse recovery occurs. The theory tested was that the elastic component that stores the energy to restore the shape of the deformed cell is primarily found in the S1 and S3 layers. In contrast, the inelastic component is primarily found in the S2 layer. The model generated here provided limited support for this theory.
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29

Blakemore, Philip. "Optimisation of steam reconditioning for regrowth-ash and plantation-grown eucalypt species". University of Sydney, 2008. http://hdl.handle.net/2123/2343.

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Doctor of Philosophy
Steam reconditioning to recover collapse, in mid to low density eucalypt species, has been known for over ninety years. The current industrial practices for steam reconditioning have largely been based on a few older studies, which were often poorly documented and based on very small sample sizes. On top of this, many local practices and ‘rules of thumb’ have developed over time, many of which have a questionable scientific basis. This thesis was undertaken to more rigorously investigate and fundamentally understand collapse recovery, and try to optimise its application. The most obvious variable that kiln operators have control over is the moisture content of the timber prior to steam reconditioning. Experiments were undertaken to generate a range of moisture gradients (ranging from minimal to more industrially realistic) to evaluate the effect of moisture content on collapse recovery. An optimal moisture content for the core of the boards was found to be between about 18–20%, although there was no statistical difference in recoveries between about 17–25% moisture content. Below 15% moisture content recovery dropped off severely and intra-ring internal checking closure was incomplete, while at 25% moisture content an increased level of normal shrinkage, due to the early removal of drying stresses, was the main drawback. Above a core moisture content of about 35% incomplete closure of intra-ring internal checks was again observed. There was little evidence of re-collapse occurring in these high moisture content samples. Previously established relationships between density and collapse and drying rate were again generally observed in these experiments. However, for the first time an effect of collapse in reducing the fitted drying diffusion coefficients was also observed. It was also observed that, provided the moisture content of the board was in the critical range, most of the collapse recovery was achieved in the time it took to get the core of the board up to the steaming temperature of close to 100°C. This suggests that for most thicknesses a conservative reconditioning period of two hours at temperature is all that is required. This recommended shortening of the reconditioning cycle could dramatically increase the throughput of timber through the steam reconditioning chambers. Alternatively, it could mean that where modern final drying kilns are being used, the reconditioning treatment could be carried out within the final drying kiln. A finite element model was developed to demonstrate the mechanism by which collapse recovery occurs. The theory tested was that the elastic component that stores the energy to restore the shape of the deformed cell is primarily found in the S1 and S3 layers. In contrast, the inelastic component is primarily found in the S2 layer. The model generated here provided limited support for this theory.
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30

Williams, Moira Caroline. "The ecological impacts of invasive Pinus radiata in eucalypt vegetation: pattern and process". School of Biological Sciences. University of Sydney, 2008. http://hdl.handle.net/2123/2761.

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Doctor of Philosophy (PhD)
Early recognition of plant invaders is key to their successful management. Yet knowledge of the ecological impacts of species before they become widespread is poor. This thesis examines the ecology of invasive Pinus radiata, a species which is known to spread from introduced plantings in Australia but is currently a low profile invader. Pinus invasions are considered major ecological problems in New Zealand and South Africa where wildlings are beginning to dominate natural areas and suppress native vegetation. Invasion success elsewhere and the large softwood estate in Australia suggest that pines may begin to dominate native eucalypt forests bordering large commercial plantations. This research focused on three components of impact of P. radiata; extent, abundance and effect per individual. The borders of 29 P. radiata plantations in NSW were surveyed in order to quantify the current level of invasion and to identify factors facilitating pine spread. Of particular interest was the role of propagule pressure, vegetation type and fire in the invasion process. The area of land in NSW currently invaded by P. radiata was estimated at almost 4 500 ha, although this is likely to be an underestimate due to an inability to detect wildlings (self-sown pines) at long distances from the plantation. Twenty six of the 29 plantations produced wild pines, however most of the sites are in the very early stages of invasion. Noticeable wildling populations were recorded at nine sites indicating that P. radiata is capable of establishing within native vegetation. Pine spread was most severe in the world heritage listed Blue Mountains region where pine densities reached up to 2000 per hectare in areas adjacent to the plantation and isolated pines were recorded up to 4 km from the source. The presence of isolated pines within intact native vegetation suggests that disturbance is not required for pine establishment in forested environments. Furthermore, high pine emergence and survival rates in eucalypt woodland and evidence of self reproduction by wildlings suggest that in the absence of adequate control measures pines may become established invaders in the Australian landscape. While low levels of current invasion at many sites hindered the ability to examine the factors facilitating invasion some variables that appear to be driving pine success were identified. At the landscape scale plantation size and residence time were significant predictors of the level of invasion at a site. Areas of native vegetation vi adjacent to plantations less than 40 years experienced very low levels of invasion suggesting a lag period between plantation establishment and invasion. However, pines with diameters up to 60 cm were observed growing adjacent to plantations younger than 40 years implying that the first colonisers are capable of establishing soon after plantation trees become reproductive. Propagule pressure was also found to have a strong influence on invasion success on a smaller scale manifesting in a significant positive relationship between the age of a plantation compartment and the likelihood of invasion. A negative relationship between plantation size and level of invasion was a surprising result and was influenced by just two large sites that happened to be located in areas of high rainfall. All sites receiving more than 1300 mm annual rainfall experienced low levels of invasion suggesting that this is a limiting factor for pine spread in NSW. There were significant differences in the level of invasion between vegetation types implying that some communities are more susceptible to invasion. Patterns of spread confirmed ideas regarding the facilitative effect of disturbance in the invasion process and the resistance of wet sclerophyll forest to invasion in Australia. An absence of wildlings in cleared land and areas of remnant bushland was attributed to high levels of grazing pressure. Wind direction did not appear to influence the distribution of pines close to the plantation, but evidence of long distance wind dispersal of pines was provided by an investigation of pine spread from the air at one site where large pines were found growing 10 km downwind from a mature plantation. Fire was found to have both a positive and negative influence on the invasion process. High intensity wildfires are capable of destroying large pines with diameters exceeding 50 cm. However, fire can stimulate seed release from cones resulting in large post-fire recruitment pulses. Seedling densities of up to 3050 per hectare were recorded almost 3 years after wildfire, suggesting that follow up control prior to recruits reaching coning age, i.e. within 5 years, would be beneficial. Surveys of wildling pines exposed to low intensity hazard reduction burns suggest that the majority of pines greater than 3 m in height and with a diameter of more than 10 cm will survive the fire. Low intensity prescribed fires that are carried out after pines have reached this size will fail to control wildling populations. To examine the influence of P. radiata once it has established in the native community this study focused on two mechanisms of impact, the addition of pine litter and increased shade due to an increase in canopy cover. Collection of pine litterfall vii within an invaded eucalypt woodland over a 2 year period recorded rates of up to 1400 kg/ha/year in the most heavily invaded area with a pine basal area of 11.3m2/ha. More than 70 % of pine litter fell directly below the pine canopy suggesting that the most severe litter effects will be limited to these areas. Glasshouse and field experiments were conducted to examine the influence of this increased litter load on the emergence of P. radiata and two native species. Recruitment of native plant species was impeded by litter levels of 6000 kg/ha, the equivalent of approximately 4 years of pine litterfall. Both P. radiata and the two natives responded similarly to pine and eucalypt litter suggesting the two litter types are influencing the recruitment phase equally. However, where pines are added to the system, increased litterfall rates could potentially result in the doubling of the litter load and hence a greater barrier to seedling establishment. Pine invaded eucalypt woodlands are also subjected to three fold increases in canopy cover. Trends in reduced emergence of native species under a pine canopy suggest that the addition of pines to eucalypt forests is likely to have a negative influence on native recruitment and may result in a shift towards a shade tolerant community. However, reversal of trends in emergence below pine canopy between seasons implies that quantifying invasion impacts requires a consideration of temporal variation. Increased levels of disturbance, forest fragmentation and an increasing pine estate are likely to lead to the infestation of new areas. Furthermore the lag phase associated with pine spread means that even if no new plantations are established the number of invasion events will increase. This study has identified a number of risk factors that can be used to guide plantation establishment and the management of invasion events. Minimising disturbance at plantation borders and increasing the ‘no planting’ zone will help to reduce the impacts of pines. Where possible new plantations should be established upwind of cleared land or at least, wet sclerophyll forest. Frequent monitoring of the borders of plantations yet to source invasions, particularly those greater than 40 years of age, will help identify problem areas before control becomes difficult and costly. Maps of the 29 plantations marked with areas of pine infestation will help prioritise sites for control and provide base level knowledge for future monitoring of pine spread. Stringent legislation that binds plantation managers to control wildlings beyond their boundaries is critical for the effective management of pine invasions. With infinite numbers of invaders and limited funds to dedicate to their control, a method of triaging species for management is critical. This is particularly difficult viii when information is typically biased towards invaders that are already widespread. By focussing on the ecological impacts of invaders it becomes possible to rank species on the basis of the threat they pose to native communities. Ecological research is capable of providing the knowledge to quantify invasion impacts and must remain at the centre of policy decisions.
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31

Pampolina, Nelson M. "Ecology of ectomycorrhizal fungi in eucalypt plantations in Western Australia and the Philippines". Thesis, Pampolina, Nelson M. (2000) Ecology of ectomycorrhizal fungi in eucalypt plantations in Western Australia and the Philippines. PhD thesis, Murdoch University, 2000. https://researchrepository.murdoch.edu.au/id/eprint/51869/.

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Eucalypts are grown in plantations around the world because of their silvicultural characteristics, economic importance and environmental values. In Australia, the establishment of new eucalypt plantations has increased to over 30,000 ha annually, supplying hardwood fibre predominantly to the Pacific Rim countries. In the Philippines, exotic eucalypts are favoured in reforestation and industrial plantation programs, but increasingly slow-growing native species are being established in fast-growing plantations. Wood production, however, in these regions is often constrained by unproductive soil due to long periods of weathering and lateritization (Western Australia), or deforestation and succession of Imperata grasslands (Philippines). Application of phosphatic fertilizers, as well as ectomycorrhizal (ECM) fungal inoculum are practised in parts of the region. However, the ecology of ECM fungi and the consequence of P application on ECM fungi have not been explored in eucalypt plantations. This thesis explores the potential role of ECM fungi in Eucalyptus globulus (W. Australia) and E. urophylla (Philippines) plantations and quantifies the effects of P application on ECM fungal dynamics. Commercial eucalypt plantations (a 2 and a 4-year-old E. globulus, a zero and a 19-month-old E. urophylla) were chosen to represent contrasting climates (mediterranean and tropical) and edaphic conditions. Basic studies on fine root growth in E. globulus and associated ECM fungi were undenaken. A 4-year-old E. globulus stand in Australia and a 19-month-old stand of E. urophylla in the Philippines were fertilized with three rates of P (nil = 0, low=100, high=1000 kg P ha-1) and effects on tree biomass, ECM fungi, soil hyphae, fine roots and litter were examined. Finally, to investigate the potential role of ECM fungi in mixed plantations, an indigenous dipterocarp species was introduced into a 25-monthold E. urophylla stand in the Philippines. Growth of fine roots in E. globulus was maximum in April (0.27 kg m-3) and minimum in August (0.09 kg m-3) when soil moistures were 5.4 and 15.6%, respectively. Over 76% of the fine root biomass and 73% of the soil hyphae were concentrated in the 0-20 cm soil horizon. Fungal diversity under the E. globulus (6 genera and 9 species) was higher than under E. urophylla (3 genera and 3 species). The common genera under E. globulus were Laccaria, Pisolithus, and Scleroderma, whereas Scleroderma and Thelephora were abundant in E. urophylla. The annual basidiocarp biomass was 18 to 23 kg ha-1 under E. globulus compared to over 5.8 kg ha-1 under E. urophylla. The application of P to E. globulus reduced the number of basidiocarps by 5 (low P) to 14 % (high P), basidiocarp and soil hyphal biomass by 26 to 40 % and 29 to 44 %, respectively, without influencing above-ground ECM fungal diversity. Whole tree biomass or litterfall was not affected, but low P increased fine root biomass in ingrowth cores at 6 months to 364 kg ha-1. Accumulation of N, P, K and Cu generally declined in fungi and litterfall with P, but P and K increased in tree biomass. The total nutrient load was in the order: above-ground tree > soil hyphae > below-ground tree > litter > fine roots > basidiocarps. By contrast, the application of P to E. urophylla had no effect on fungal diversity, fungal biomass, tree growth or litter production, but substantially reduced soil hyphal length by 31 to 52%. The nutrient content of E. urophylla aboveground was approximately equal to the sum of the nutrient load in roots, litter and ECM fungi. In the E. urophylla plantation where Shorea contorta was introduced, there were 4 ECM fungal species above-ground and 18 ECM morphotypes (11 in 5. contorta and 7 in E. urophylla) below-ground. From RFLP analysis, it was concluded that some species of Scleroderma were able to naturally colonize roots of Shorea and Eucalyptus. Outplanted S. contorta, which were mycorrhizal, had better survival (33-48%) than non-mycorrhizal plants at 18 months.
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32

Piper, Scott Douglas. "Effects of Habitat Fragmentation on Avian Nesting Success within Subtropical Australian Eucalypt Forests". Thesis, Griffith University, 2007. http://hdl.handle.net/10072/366541.

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Fragmentation-related increases in levels of predation at birds’ nests, and changes to nest predator assemblages, have often been reported in Northern Hemisphere temperate forests. In many cases these changes have been attributed to an influx of matrix-associated avian predators from neighbouring agricultural or urbanised land. Well-documented increases in the abundance of avian nest predators, which are ecologically similar to those causing edge effects elsewhere, occur in Australian agricultural and urban habitats, and near edges within remnant eucalypt forests. Therefore, increases in levels of nest predation, similar to those occurring elsewhere, may be expected to occur near edges and within small remnant patches of Australian eucalypt forests. The same processes would not be expected to occur at the edges of eucalypt forests which border plantations of exotic Pinus tree species, because edge-related nest predation has seldom been reported in Northern Hemisphere temperate forest mosaics. Furthermore, avian nest predators do not generally increase within Australian Pinus plantations, or near edges within remnant forests fragmented by Pinus plantations. The primary aim of this thesis was to assess the potential impacts of habitat fragmentation on levels of predation at birds’ nests, and predator assemblage composition, within subtropical Australian eucalypt forests. Four separate experiments were conducted in south east Queensland’s lowland eucalypt forests. A common methodology was employed throughout, consisting of deploying five or ten artificial open-cup nests along a transect, each baited with a quail egg, and with two imprint-receptive plasticine eggs which allowed assessment of the nest predator assemblages. These nests were exposed for six or seven days, to estimate nest predation levels and assess nest predator assemblages amongst a variety of contexts. In each experiment, treatments consisted of differing fragmentation contexts, in which there were replicate sites which were distributed across a wide area at the landscape scale. Throughout these experiments the unit of replication was a site containing a single transect, and two nest predation measures were used: 1. predation of the quail egg, providing a more conservative predation measure involving larger, stronger predators which would be less likely to be thwarted by parental defence at a real nest; and 2. predation of any egg, which provides a less conservative measure that is likely to include activity by even the smallest potential nest predators. In an initial experiment, effects of distance to edge and type of adjoining land use were tested within large (>400 ha) eucalypt forest remnants. Shrub-nests were deployed at distances of 0-30, 60-90, and 235-265 metres from edges adjacent to areas of urban, pasture, and Pinus plantation. There were eight replicate sites of each edge type, scattered widely across a 30 000 km2 study area. When predation of the quail egg was used to calculate predation levels, predation varied significantly with edge type but not distance to the edge, due to relatively low levels of predation within sites bordering Pinus plantations. When predation of any egg was used to calculate predation levels, predation was not significantly affected by edge type or distance to the edge. Predation levels within eight independent forest interior transects, distributed throughout the study region and located 500-800 m from the nearest edge, were similar to those within transects 0 m from edges. Birds were the most important class of predator within all combinations of site type and distance to edge, and accounted for 92% of predation events for which a predator could be identified. In most of these cases, damage to imprint-receptive eggs was consistent with large-bodied nest-depredating species bird species from the family Artamidae (butcherbirds, currawongs and Australian magpie). In a second experiment, potential effects of edge and type of adjoining land use on predation at artificial nests were again assessed within large (>400 ha) eucalypt forest remnants, using a different spatial layout of sites over a region of about 10 000 km2. Nine sites were selected in each of three contexts: forest/pasture edge, forest/urban edge, and forest interior. Edge sites were 0-30 m from edges, and interiors were located 500-1000 m from the nearest edge. Within each site, nests were placed at each of two heights (ground and shrub), and this experimental design was used yearly for three years at interior and urban edge sites, and two years at pasture edge sites. Averaged across the three years, 62% more ground-nests, and 54% more shrub-nests, were depredated near edges than within forest interiors. Furthermore, complete depredation of all nests within a site was much more common near edges than within forest interiors, particularly for shrub-nests. Predators were identified for 250 of 369 depredated nests, of which 80% had been preyed upon by birds, 12% by mammals, and 7% by reptiles. It is argued that the increase in predation at edges was primarily caused by large-bodied avian predators, particularly species within the family Artamidae. The general occurrence of edge-related nest predation in subtropical eucalypt forests was further supported by a third experiment, which investigated potential impacts of internal fragmentation by picnic areas on nest predation. Bird assemblages and nest predation levels at eight transects abutting picnic areas (‘picnic area edges’) were compared with two types of matched control transect within forest about 150 m away ( ‘forest interiors’), and, ‘context references’, which were similar to the picnic area edges in their proximity to access roads and forest external edges. Within the picnic areas there was an assemblage of relatively large-bodied, aggressive birds, including several avian nest predators (Torresian crow, grey and pied butcherbirds) as well as the Australian magpie and noisy miner, resembling that found in urban areas within the study region. Bird assemblages at picnic area edges, which were dominated by the noisy miner and Australian magpie, clearly differed from those of forest interiors, which were characterised by a number of smaller-bodied insectivorous species. Levels of predation at artificial nests were several-fold greater adjacent to the picnic areas than at forest interiors 150 m from the picnic area edges. Context reference transects were similar to forest interiors when associated with narrow roads, but similar to picnic area edges when associated with roads incorporating wide grassy verges. These results showed that picnic areas exert strong localised edge effects on forest bird assemblages, and appeared likely to cause reduced reproductive success for small-bodied forest bird species if they attempted to nest nearby. A fourth experiment investigated whether levels of nest predation and predator assemblages varied between interiors of small (10-20 ha) urban remnant patches (>50 m from external edges), and extensive tracts (>400 ha) of subtropical Australian eucalypt forest (>500 m from external edges). Artificial nests were deployed both on the ground and in shrubs. Most predation of shrub-nests in both remnants and extensive forests was by birds, although there were some differences in the assemblages involved. Ground-nests were far more likely to be depredated by mammals or lizards in the remnants than in the extensive forests. This may have been caused by mesopredator release, or because small remnants provided more favourable habitat than extensive forests for these predators. However, overall nest predation levels did not differ significantly between remnants and extensive forests, suggesting that any edge-related predation was of insufficient spatial extent to strongly affect the interiors of remnants in this size class. Finally, nest predation results from the second and fourth experiments were reassessed with respect to landscape composition. The relationship between nest predation levels and the proportional cover of pasture, crop, settlement, and forest, within a 5 km radius of each site was investigated. There was no significant association between nest predation levels and surrounding landscape composition at that scale, suggesting that the occurrence of more local scale impacts (such as edge effects) was not influenced by landscape-scale processes. Edge-related nest predation in North American and European forests has often been explained with reference to an influx of relatively large-bodied avian nest predators from the matrix, where they show increases in abundance and diversity compared with unfragmented forests. Species of predator which have often been implicated have included the blue jay and American crow in North America, and the magpie, hooded crow, and jay in Europe. They may proliferate within agricultural and urbanised landscapes because of increased foraging opportunities, and then may penetrate some distance into remnant forests. Fragmentation had been expected to similarly cause increases to nest predation levels within Australian eucalypt forests because bird assemblages within Australian pasture and urban habitats are often dominated by relatively aggressive, medium- to large-bodied native species, including nest predators such as the laughing kookaburra, and species from the families Corvidae and Artamidae. My results supported the general occurrence of such an edge effect of increased predation at birds’ nests within eucalypt forests. However, this effect was caused by sedentary avian species which show increased abundances at edges within eucalypt forests, rather than by an influx of avian predators from the matrix.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
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33

Williams, Moira Caroline. "The ecological impacts of invasive Pinus radiata in eucalypt vegetation: pattern and process". Thesis, The University of Sydney, 2007. http://hdl.handle.net/2123/2761.

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Early recognition of plant invaders is key to their successful management. Yet knowledge of the ecological impacts of species before they become widespread is poor. This thesis examines the ecology of invasive Pinus radiata, a species which is known to spread from introduced plantings in Australia but is currently a low profile invader. Pinus invasions are considered major ecological problems in New Zealand and South Africa where wildlings are beginning to dominate natural areas and suppress native vegetation. Invasion success elsewhere and the large softwood estate in Australia suggest that pines may begin to dominate native eucalypt forests bordering large commercial plantations. This research focused on three components of impact of P. radiata; extent, abundance and effect per individual. The borders of 29 P. radiata plantations in NSW were surveyed in order to quantify the current level of invasion and to identify factors facilitating pine spread. Of particular interest was the role of propagule pressure, vegetation type and fire in the invasion process. The area of land in NSW currently invaded by P. radiata was estimated at almost 4 500 ha, although this is likely to be an underestimate due to an inability to detect wildlings (self-sown pines) at long distances from the plantation. Twenty six of the 29 plantations produced wild pines, however most of the sites are in the very early stages of invasion. Noticeable wildling populations were recorded at nine sites indicating that P. radiata is capable of establishing within native vegetation. Pine spread was most severe in the world heritage listed Blue Mountains region where pine densities reached up to 2000 per hectare in areas adjacent to the plantation and isolated pines were recorded up to 4 km from the source. The presence of isolated pines within intact native vegetation suggests that disturbance is not required for pine establishment in forested environments. Furthermore, high pine emergence and survival rates in eucalypt woodland and evidence of self reproduction by wildlings suggest that in the absence of adequate control measures pines may become established invaders in the Australian landscape. While low levels of current invasion at many sites hindered the ability to examine the factors facilitating invasion some variables that appear to be driving pine success were identified. At the landscape scale plantation size and residence time were significant predictors of the level of invasion at a site. Areas of native vegetation vi adjacent to plantations less than 40 years experienced very low levels of invasion suggesting a lag period between plantation establishment and invasion. However, pines with diameters up to 60 cm were observed growing adjacent to plantations younger than 40 years implying that the first colonisers are capable of establishing soon after plantation trees become reproductive. Propagule pressure was also found to have a strong influence on invasion success on a smaller scale manifesting in a significant positive relationship between the age of a plantation compartment and the likelihood of invasion. A negative relationship between plantation size and level of invasion was a surprising result and was influenced by just two large sites that happened to be located in areas of high rainfall. All sites receiving more than 1300 mm annual rainfall experienced low levels of invasion suggesting that this is a limiting factor for pine spread in NSW. There were significant differences in the level of invasion between vegetation types implying that some communities are more susceptible to invasion. Patterns of spread confirmed ideas regarding the facilitative effect of disturbance in the invasion process and the resistance of wet sclerophyll forest to invasion in Australia. An absence of wildlings in cleared land and areas of remnant bushland was attributed to high levels of grazing pressure. Wind direction did not appear to influence the distribution of pines close to the plantation, but evidence of long distance wind dispersal of pines was provided by an investigation of pine spread from the air at one site where large pines were found growing 10 km downwind from a mature plantation. Fire was found to have both a positive and negative influence on the invasion process. High intensity wildfires are capable of destroying large pines with diameters exceeding 50 cm. However, fire can stimulate seed release from cones resulting in large post-fire recruitment pulses. Seedling densities of up to 3050 per hectare were recorded almost 3 years after wildfire, suggesting that follow up control prior to recruits reaching coning age, i.e. within 5 years, would be beneficial. Surveys of wildling pines exposed to low intensity hazard reduction burns suggest that the majority of pines greater than 3 m in height and with a diameter of more than 10 cm will survive the fire. Low intensity prescribed fires that are carried out after pines have reached this size will fail to control wildling populations. To examine the influence of P. radiata once it has established in the native community this study focused on two mechanisms of impact, the addition of pine litter and increased shade due to an increase in canopy cover. Collection of pine litterfall vii within an invaded eucalypt woodland over a 2 year period recorded rates of up to 1400 kg/ha/year in the most heavily invaded area with a pine basal area of 11.3m2/ha. More than 70 % of pine litter fell directly below the pine canopy suggesting that the most severe litter effects will be limited to these areas. Glasshouse and field experiments were conducted to examine the influence of this increased litter load on the emergence of P. radiata and two native species. Recruitment of native plant species was impeded by litter levels of 6000 kg/ha, the equivalent of approximately 4 years of pine litterfall. Both P. radiata and the two natives responded similarly to pine and eucalypt litter suggesting the two litter types are influencing the recruitment phase equally. However, where pines are added to the system, increased litterfall rates could potentially result in the doubling of the litter load and hence a greater barrier to seedling establishment. Pine invaded eucalypt woodlands are also subjected to three fold increases in canopy cover. Trends in reduced emergence of native species under a pine canopy suggest that the addition of pines to eucalypt forests is likely to have a negative influence on native recruitment and may result in a shift towards a shade tolerant community. However, reversal of trends in emergence below pine canopy between seasons implies that quantifying invasion impacts requires a consideration of temporal variation. Increased levels of disturbance, forest fragmentation and an increasing pine estate are likely to lead to the infestation of new areas. Furthermore the lag phase associated with pine spread means that even if no new plantations are established the number of invasion events will increase. This study has identified a number of risk factors that can be used to guide plantation establishment and the management of invasion events. Minimising disturbance at plantation borders and increasing the ‘no planting’ zone will help to reduce the impacts of pines. Where possible new plantations should be established upwind of cleared land or at least, wet sclerophyll forest. Frequent monitoring of the borders of plantations yet to source invasions, particularly those greater than 40 years of age, will help identify problem areas before control becomes difficult and costly. Maps of the 29 plantations marked with areas of pine infestation will help prioritise sites for control and provide base level knowledge for future monitoring of pine spread. Stringent legislation that binds plantation managers to control wildlings beyond their boundaries is critical for the effective management of pine invasions. With infinite numbers of invaders and limited funds to dedicate to their control, a method of triaging species for management is critical. This is particularly difficult viii when information is typically biased towards invaders that are already widespread. By focussing on the ecological impacts of invaders it becomes possible to rank species on the basis of the threat they pose to native communities. Ecological research is capable of providing the knowledge to quantify invasion impacts and must remain at the centre of policy decisions.
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34

Low, Petah Alexandra. "The ecology and behaviour of eucalypt-feeding caterpillars in response to predation risk". Thesis, The University of Sydney, 2016. http://hdl.handle.net/2123/15898.

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It was traditionally assumed that predator effects were lethally transmitted, however there is now increasing evidence of the importance of their non-consumptive effects. I outline a conceptual framework that integrates both the consumptive and non-consumptive pathways for predator effects on insect herbivores. Using this framework, I aimed to improve our understanding of predator effects on insect herbivores in the Eucalyptus system. First I investigated how the plant traits- leaf age and location- affect predation risk, and also whether this risk varied with type of predator. I found no evidence for a difference in risk. I then manipulated head capsule stacks on Uraba lugens larvae to investigate their putative defensive function. I found that the retention of moulted head capsules provides some protection against natural enemies by serving as a false target as well as a weapon to fend off attackers. Next I investigated the behavioural responses of caterpillars to variation in a direct physical cue of predation risk, non-lethal predator attacks varying in location and frequency. I found that the type and extent of response varied according to the location and frequency of attack, suggesting that these caterpillars have the capacity to distinguish different levels of risk. I also investigated how both the behaviour and physiology of caterpillars are influenced by multiple cues of predation risk. I found that the direct physical cue invoked both short term behavioural responses and long-term physiological ones, while the indirect chemical cue invoked only short-term physiological responses. Finally my thesis also addressed a number of methodological aims regarding the use of model prey. I confirmed the validity of models as surrogates for real prey in a field setting. I also collated a comprehensive reference collection of attack marks and established guidelines for identifying predators responsible for attacks on models.
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35

Guedes, Marcelino Carneiro. "Ciclagem de nutrientes após aplicação de lodo de esgoto (Biossólido) sobre latossolo cultivado com Eucalyptus grandis". Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-09112005-134208/.

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O tratamento das águas residuárias gera um resíduo, o lodo de esgoto, que poderia ser utilizado para aumentar a produtividade de culturas agrícolas e florestais. O objetivo geral deste trabalho foi estudar como a utilização do biossólido em um povoamento de Eucalyptus grandis afeta a ciclagem biogeoquímica de nutrientes. O estudo foi desenvolvido na Estação Experimental de Itatinga, vinculada ao Departamento de Ciências Florestais da ESALQ/USP. O experimento foi instalado em março de 1998 em um delineamento em blocos casualizados, com cinco tratamentos (testemunha, adubação mineral, 10 Mg ha-1 de biossólido + KP, 20 Mg ha-1 de biossólido + K e 40 Mg ha-1 de biossólido + K). Os resultados mostraram que a aplicação de biossólido alterou o desenvolvimento e o estado nutricional dos eucaliptos, bem como os padrões de reciclagem dos nutrientes. A produção de fitomassa arbórea pelos eucaliptos que receberam 10 Mg ha-1 de biossólido + K e P mineral foi significativamente maior do que no tratamento testemunha e, em média, maior também do que na fertilização mineral. Com as doses de biossólido, também foi verificado um significativo aumento na produção de serapilheira e na devolução de nutrientes ao solo. Durante quatro anos de desenvolvimento, as árvores que receberam a maior dose de biossólido produziram e devolveram ao solo 20 Mg ha-1 de folhedo, 5340 kg ha-1 de folhas senescentes a mais do que as árvores testemunhas e 2422 kg ha-1 a mais do que os eucaliptos que receberam adubação. O biossólido alcalino utilizado apresentou reduzidas taxas de degradação. Apenas o biossólido que foi aplicado em uma dose de 20 Mg ha-1 diminuiu sua massa seca em mais de 50%, chegando a taxa média igual a 2,42 Mg ha-1 ano-1. A aplicação de biossólido não alterou a taxa de perda de massa do folhedo de eucalipto. No entanto, o resíduo afetou a dinâmica de mineralização e liberação de nutrientes, principalmente, evitando a imobilização de N e acelerando sua liberação das folhas em decomposição. Os eucaliptos do tratamento "10+KP" apresentaram maior quantidade de fitomassa epígea acumulada em todos os componentes, o que resultou em 62% a mais de fitomassa total nessas árvores em relação às testemunhas. Para esses eucaliptos, que apresentaram maior produtividade, a fitomassa total de tronco acumulada em cinco anos foi de 94,9 Mg ha-1; conseqüentemente, o incremento médio anual (IMA) foi de 19 Mg ha-1 ano-1. Este tratamento “10+KP” apresentou também maior mineralomassa de N, P, S e Zn. Por outro lado, apresentou menores valores de mineralomassa de Ca do que os os tratamentos “20+K” e “40+K”, assim como menor mineralomassa de Mg do que os eucaliptos que receberam adubação mineral. A aplicação de biossólido propiciou, na fase final da rotação, maiores estoques de nutrientes em todos os compartimentos do ecossistema. O capital lábil de P, Ca e Zn no solo onde foi aplicado biossólido foi maior do que no solo adubado, o que evidencia maior capacidade em manter a sustentabilidade produtiva do ecossistema quando se aplica biossólido.
The treatment of wastewaters generates the sewage sludge, a residue that could be used to increase the productivity of both farming and forest plantations. The general aim of this work was to evaluate how biosolid affects the biogeochemistry of nutrients at an Eucalyptus grandis plantation. The study site is at the Experimental Station of Itatinga, linked to the Forest Sciences Department of the ESALQ/USP. The trial was installed on March 1998 in randomized blocks design, with five treatments (control, inorganic mineral fertilizer, 10 Mg ha-1 of biosolid + KP, 20 Mg ha-1 of biosolid + K and 40 Mg ha-1 of biosolid + K). The results showed that the biosolid application alters both the development and the nutritional state of eucalypts, as well as the patterns of nutrients recycling. There was an significant increment in the arboreal biomass production of the eucalypts that received 10 Mg ha-1 of biosolid + mineral K e P, in relation to the control treatment, and higher average production than the eucalypts that received full mineral fertilization. With the increase of biosolid rates, there was a significant increase on the production of litter-fall and on the nutrients soil devolution. During four years, the trees under the largest biosolid dose produced and returned to the soil 20 Mg of leaves-fall, 5340 kg more than the control trees and 2422 kg more than the eucalypts that received fertilization. The used alkaline biosolid presents reduced degradation rates. Just the biosolid applied at a 20 Mg ha-1 dose reduced the dry mass by more that one half, reaching a medium rate of 2.42 Mg ha-1 year-1. The biosolid application does not alter the leaves-fall eucalypts mass loss rate, appraised in senescent leaves. However, the residue affects the mineralization dynamics and nutrients liberation, mainly, by blocking the immobilization of N and accelerating its liberation from the leaves decomposing. The eucalypts under the treatment "10+KP" presented more accumulated biomass in all of their components, so they reached 62% more aboveground biomass in comparison to the control plants. For those eucalypts that presented the highest productivity, the total biomass of trunk accumulated in five years was 94,9 Mg ha-1; consequently, the mean annual increment (MAI) was of 19 Mg ha-1 year-1. The treatment "10+KP" also presented high mineral mass of N, P, S and Zn. By the other hand, the treatment "10+KP" presents smaller values of mineral mass of Ca than the eucalypts under the treatments "20+K" and "40+K" and smaller mineral mass of Mg than the eucalypts that received mineral fertilization. In the final phase of the rotation, the biosolid increased the nutrients stocks in all compartments of the ecosystem. The P, Ca and Zn labile pool soil was higher with biosolid application than fertilized soil, what assures higher capacity in maintaining sustainability productivity of the ecosystem when biosolid is applied.
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36

Leite, Regina Marques [UNESP]. "Efeito da escória de siderurgia na nutrição e desenvolvimento inicial de eucalipto". Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/90609.

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A escória de siderurgia é um dos resíduos gerados durante a produção de ferro-gusa. O Brasil é um dos maiores produtores de ferro-gusa e isso significa geração de aproximadamente dez milhões de toneladas por ano deste passivo ambiental. Entretanto, as escórias básicas de siderurgia podem ser usadas como corretivos de acidez do solo, fornecendo cálcio, magnésio e silício, sendo que o seu uso evita a extração de outros produtos da natureza, como o calcário, por exemplo. Os objetivos deste trabalho foram avaliar a influência das escórias de siderurgia no crescimento e nutrição do eucalipto na sua fase inicial (6 meses pós plantio) e nos atributos químicos do solo. O experimento foi conduzido em Latossolo e Neossolo Quartzarênico e foi analisado de duas formas: 1ª) avaliação do efeito da aplicação de doses crescentes de escória (doses proporcionais a zero; 300; 600; 1200 e 2400 kg/ha); e 2ª) comparação do tratamento equivalente a 2400 kg/ha de escória com testemunha absoluta, adubação química (somente NPK) e calcário. O delineamento experimental foi o de blocos inteiramente casualizados, com seis repetições. Foram realizadas análises químicas de solo aos três e aos seis meses após o início da condução do experimento. Avaliou-se mensalmente a altura e o diâmetro das plantas e, ao encerramento, quantificou-se massa verde e massa seca de folhas, galhos, tronco e raízes, área foliar, teores de macro e micronutrientes e silício nas folhas, galhos, tronco e raízes. Os dados foram analisados estatisticamente com o auxílio do programa SISVAR.2 Os resultados indicaram que, após três meses, a aplicação de 2400 kg/ha de escória proporcionou aumento do pH e V% do solo e redução da acidez potencial em ambos os solos. Após seis meses do plantio, os valores de pH foram semelhantes quando se comparou a dose de 2400 kg/ha com o calcário...
Blast furnace slag is one of residues generated during cast-iron production. Brazil is one of the largest producers of cast-iron. This means the generation of approximately ten million tonnes per year of environmental liabilities. However, slag can be used as soil pH-correcting material supplying calcium, magnesium and silicon, and that its use prevents the extraction of other products of nature, such as limestone, for example. The objectives of this study were to evaluate the influence of blast furnace slags on growth and nutrition of eucalyptus in its initial phase (6 months after planting) and chemical soil attributes. The experiment was conducted in Oxisol and a Typic Quartzipsamment and was analyzed in two ways: 1st) evaluation of the effect of application of increasing slag doses (rates proportional to zero, 300, 600; 1200 and 2400 kg / ha), and 2nd) comparison of a treatment equivalent to 2400 kg / ha of slag against an absolute control, chemical fertilization (NPK only) and limestone. The experimental design consisted of completely randomized blocks with six repetitions. Soil chemical analyses were performed three and six months after installation of the experiment. It was evaluated monthly height and diameter of the plants and the closure, is quantified green and dry mass of leaves, branches, trunk and roots, leaf area; macronutrient, micronutrient, and silicon in the leaves, branches, trunk and roots . The data were analyzed statistically using the SISVAR software program. The results indicated that, after three months, the application of 2400 kg / ha of slag increased soil pH and V%, and decreased potential acidity in both soils. Six months after planting, pH values were similar when the 2,400 kg / ha dose was compared with the dose of limestone. Increased slag doses provided increased green and dry mass production of leaves, leaf area, and dry mass of branches, increased leaf... (Complete abstract click electronic acess below)
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SILVA, Diene Elen Miranda da. "Quantifica??o da resist?ncia parcial em esp?cies de eucalipto ? ferrugem (Puccinia psidii)". Universidade Federal Rural do Rio de Janeiro, 2012. https://tede.ufrrj.br/jspui/handle/jspui/1764.

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The incidence of rust occurs on nursery seedlings and plants in the field, this disease caused by of Puccinia psidii is the most severe on Eucalyptus tree. The objective of this work is to quantify the partial resistance of ten species of Eucaliptus: E. propinqua, E. citriodora, E. grandis, E. urophylla, E. microcorys, E. urograndis, E. robusta, E. saligna, E. dunni and E. phaeotricha to eucalypt rust. For it some experiments were performed in greenhouse of Department of Entomology and Plant Pathology of UFRRJ. Were used 200 eucalypt seedlings of 3 months old obtained from seeds. The experimental design was totally randomized, with 10 treatments and 10 repetitions, with 1 plant to each repetition. The inoculation was performed by atomization of leaves with suspension of urediniospores in the concentration of 2x 104 spores/mL, obtained from fresh pustules. Later the seedlings were incubated in wet chamber in the dark by 48 hours. The parameters of resistance evaluated were: number of pustules by leaflet, severity, average latent period, AUDPC (area under the disease progress curve). The data otained were transformed too 0,5 and ?and submitted to ANOVA and mean comparison by Scott-Knott test at 5% probability, using the software SAEG. Meaningful differences were found among the eucalypt species for the parameters studied. The species E. urograndis showed a lower average number of pustules per leaflet, lower severity, greater mean latent period and small values of AUDPC (area under the disease progress curve), thus showing greater partial resistance to the rust.
A incid?ncia da ferrugem ocorre em mudas de viveiro e em plantas jovens no campo, essa doen?a causada por Puccinia psidii ? uma das mais severas do eucalipto. O presente trabalho teve como objetivo quantificar a resist?ncia parcial de dez esp?cies de Eucaliptus: E. propinqua, E. citriodora, E. grandis, E. urophylla, E. microcorys, E. urograndis, E. robusta, E. saligna, E. dunni e E. phaeotricha ? ferrugem do eucalipto. Para isso foram conduzidos dois experimentos em casa de vegeta??o no Departamento de Entomologia e Fitopatologia da UFRRJ. Foram utilizadas 200 mudas de eucalipto com tr?s meses de idade, obtidas a partir de sementes. O delineamento experimental utilizado foi inteiramente casualizado, com dez tratamentos e dez repeti??es, sendo uma planta por repeti??o. A inocula??o foi realizada por meio da atomiza??o de folhas com suspens?o de uredosporos na concentra??o de 2x104 esporos/mL, obtidos a partir de p?stulas frescas. Em seguida, as mudas foram incubadas em c?mara ?mida e escura por 48h. Foram avaliados os par?metros de resist?ncia: n?mero m?dio de p?stulas por fol?olo, severidade, per?odo latente m?dio e AACPD. Os dados obtidos foram transformados em 0,5 e ?100, e submetidos ? an?lise de vari?ncia e ? compara??o de m?dias pelo teste de Scott-Knott ao n?vel de 5% de probabilidade, por meio do software SAEG. Foram encontradas diferen?as significativas entre as esp?cies de eucalipto para os par?metros estudados. A esp?cie E. urograndis apresentou um menor n?mero m?dio de p?stulas por fol?olo, menor severidade, maior per?odo latente m?dio e valores menores da ?rea abaixo da curva do progresso da doen?a, tendo dessa forma maior resist?ncia parcial ? ferrugem.
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Almado, Roosevelt de Paula. "Flutuação populacional de lepidópteros desfolhadores de eucalipto em Bom Despacho, Minas Gerais". Universidade Federal de Viçosa, 2006. http://locus.ufv.br/handle/123456789/3978.

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The objective of this work was to identify the species of Lepidoptera primary pests for the eucalyptus and to evaluate the influence of the temperature and rainfall on their population fluctuation in the area of Bom Despacho, Minas Gerais State, Brazil. Five light traps were used during one night, every fifteen days, from January 1994 to December 2001. The species collected were Thyrinteina arnobia and Oxydia vesulia (Geometridae), Sarsina violascens (Lymantriidae), Psorocampa denticulata (Notodontidae) and Eupseudosoma aberrans (Arctiidae). A total of 12,040.5 individuals were collected per trap, being T. arnobia the most abundant species, with 96.05% of the individuals during the eight years of collection. The largest number of individuals was collected in April and May, indicating that the outbreaks of these species are concentrate in these months. T. arnobia had no significant correlations with the temperature and the rainfall but O. vesulia had negative correlation with the rainfall. S. violascens and E. aberrans presented similar population fluctuation with negative correlation with the temperature and the rainfall. P. denticulata presented positive correlation with these factors. The Lepidoptera primary pests of eucalyptus collected in the area of Bom Despacho presented higher number of individuals in the coldest and dry months of the year, especially in April and May, except P. denticulata. This last species had higher number of individuals collected in October and November and in February and March at the beginning and the final of the raining season.
O objetivo deste trabalho foi identificar as espécies de lepidópteros pragas primárias para o eucalipto e avaliar a influência da temperatura e da precipitação pluviométrica na flutuação populacional das mesmas na região de Bom Despacho, Minas Gerais, Brasil. Foram utilizadas cinco armadilhas luminosas acionadas durante uma noite, a cada quinze dias, de janeiro de 1994 a dezembro de 2001. As espécies coletadas foram Thyrinteina arnobia e Oxydia vesulia (Geometridae), Sarsina violascens (Lymantriidae), Psorocampa denticulata (Notodontidae) e Eupseudosoma aberrans (Arctiidae). Foram coletados 1.2040,5 indivíduos por armadilha, sendo T. arnobia a espécie mais abundante, com 96,05% dos indivíduos coletados durante os oito anos de coleta. O maior número de indivíduos foi coletado em abril e maio, indicando que os surtos dessas espécies se concentram nesses meses. Não verificou-se correlação significativa da temperatura e da precipitação pluviométrica com T. arnobia, mas O. vesulia teve correlação negativa com a precipitação pluviométrica. S. violascens e E. aberrans apresentaram flutuação semelhante, com correlações negativas com a temperatura e a precipitação pluviométrica. P. denticulata apresentou correlação positiva para esses fatores. Os lepidópteros pragas primárias de eucalipto coletados, na região de Bom Despacho, apresentaram maior número de indivíduos nos meses mais frios e secos do ano, nos meses de abril e maio, exceto P. denticulata que teve maior número de indivíduos coletados de outubro a novembro e de fevereiro a março coincidindo com o início e final do período chuvoso.
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39

au, asmith@murdoch edu, i Amanda Jessica Smith. "Campsite impact monitoring in the temperate eucalypt forests of Western Australia: An integrated approach". Murdoch University, 2004. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040504.151201.

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This study assessed the social and biophysical impacts of camping in the eucalypt forests of southwestern Western Australia. This was an integrated study examining both biophysical and social impacts in designated, developed and informal recreation areas used for camping. Four existing and proposed national parks and a Reserve, comprised of 110 designated and 12 informal campsites, provided the study sites. Previous research has focused on backcountry campsites and trails in wilderness areas in United States. A combined survey approach using multiple indicator ratings and measures was used to assess the biophysical impacts of camping. Adjustments to monitoring procedures used in backcountry areas were made so that the indicators were applicable to designated, developed campsites where a management footprint has been imposed. Visitors were surveyed at the designated campsites to establish how existing recreation opportunities were being used. Further, potential indicators and standards were identified to determine what kinds of social and resource conditions were acceptable to visitors and managers. A rating system was then developed combining biophysical and social indicators of importance to visitors and managers with their perceptions of acceptable change obtained from the surveys. Based on the indices derived from the rating system and results for a suite of associated indicators, designated campsites were significantly less impacted than informal ones. For both campsite types the amount of tree damage and litter exceeded the standards set by 50% of visitors and managers. Both visitors and managers were generally more concerned about biophysical impacts than they were about social ones, although site cleanliness was of concern. Both were generally satisfied with the size and number of groups encountered, in contrast to study findings from the United States. This study has developed and successfully applied an integrated approach to monitoring the impacts of recreational use on forested campsites in southwestern Australia. This system effectively and efficiently uses a combination of multiple indicator ratings and measures to produce an impact index, plus social surveys to provide information on conditions, indicators and standards of importance to managers and visitors. It also provides a means for the first time, of objectively monitoring designated, developed campsites where it is inappropriate to judge impacts against an undisturbed control.
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40

Smith, Amanda Jessica. "Campsite impact monitoring in the temperate eucalypt forests of Western Australia: an integrated approach". Smith, Amanda Jessica (2004) Campsite impact monitoring in the temperate eucalypt forests of Western Australia: an integrated approach. PhD thesis, Murdoch University, 2004. http://researchrepository.murdoch.edu.au/316/.

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This study assessed the social and biophysical impacts of camping in the eucalypt forests of southwestern Western Australia. This was an integrated study examining both biophysical and social impacts in designated, developed and informal recreation areas used for camping. Four existing and proposed national parks and a Reserve, comprised of 110 designated and 12 informal campsites, provided the study sites. Previous research has focused on backcountry campsites and trails in wilderness areas in United States. A combined survey approach using multiple indicator ratings and measures was used to assess the biophysical impacts of camping. Adjustments to monitoring procedures used in backcountry areas were made so that the indicators were applicable to designated, developed campsites where a management footprint has been imposed. Visitors were surveyed at the designated campsites to establish how existing recreation opportunities were being used. Further, potential indicators and standards were identified to determine what kinds of social and resource conditions were acceptable to visitors and managers. A rating system was then developed combining biophysical and social indicators of importance to visitors and managers with their perceptions of acceptable change obtained from the surveys. Based on the indices derived from the rating system and results for a suite of associated indicators, designated campsites were significantly less impacted than informal ones. For both campsite types the amount of tree damage and litter exceeded the standards set by 50% of visitors and managers. Both visitors and managers were generally more concerned about biophysical impacts than they were about social ones, although site cleanliness was of concern. Both were generally satisfied with the size and number of groups encountered, in contrast to study findings from the United States. This study has developed and successfully applied an integrated approach to monitoring the impacts of recreational use on forested campsites in southwestern Australia. This system effectively and efficiently uses a combination of multiple indicator ratings and measures to produce an impact index, plus social surveys to provide information on conditions, indicators and standards of importance to managers and visitors. It also provides a means for the first time, of objectively monitoring designated, developed campsites where it is inappropriate to judge impacts against an undisturbed control.
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Smith, Amanda Jessica. "Campsite impact monitoring in the temperate eucalypt forests of Western Australia : an integrated approach /". Access via Murdoch University Digital Theses Project, 2003. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040504.151201.

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Thesis (Ph.D.)--Murdoch University, 2003.
Thesis submitted to the Division of Science and Engineering. "Supported by CRC for Sustainable Tourism and Dept of Conservation and Land Management (Western Australia)". Bibliography: leaves 334-355.
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42

Smith, Amanda J. "Campsite impact monitoring in the temperate eucalypt forests of Western Australia: An integrated approach". Thesis, Smith, Amanda J. (2004) Campsite impact monitoring in the temperate eucalypt forests of Western Australia: An integrated approach. PhD thesis, Murdoch University, 2004. https://researchrepository.murdoch.edu.au/id/eprint/316/.

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This study assessed the social and biophysical impacts of camping in the eucalypt forests of southwestern Western Australia. This was an integrated study examining both biophysical and social impacts in designated, developed and informal recreation areas used for camping. Four existing and proposed national parks and a Reserve, comprised of 110 designated and 12 informal campsites, provided the study sites. Previous research has focused on backcountry campsites and trails in wilderness areas in United States. A combined survey approach using multiple indicator ratings and measures was used to assess the biophysical impacts of camping. Adjustments to monitoring procedures used in backcountry areas were made so that the indicators were applicable to designated, developed campsites where a management footprint has been imposed. Visitors were surveyed at the designated campsites to establish how existing recreation opportunities were being used. Further, potential indicators and standards were identified to determine what kinds of social and resource conditions were acceptable to visitors and managers. A rating system was then developed combining biophysical and social indicators of importance to visitors and managers with their perceptions of acceptable change obtained from the surveys. Based on the indices derived from the rating system and results for a suite of associated indicators, designated campsites were significantly less impacted than informal ones. For both campsite types the amount of tree damage and litter exceeded the standards set by 50% of visitors and managers. Both visitors and managers were generally more concerned about biophysical impacts than they were about social ones, although site cleanliness was of concern. Both were generally satisfied with the size and number of groups encountered, in contrast to study findings from the United States. This study has developed and successfully applied an integrated approach to monitoring the impacts of recreational use on forested campsites in southwestern Australia. This system effectively and efficiently uses a combination of multiple indicator ratings and measures to produce an impact index, plus social surveys to provide information on conditions, indicators and standards of importance to managers and visitors. It also provides a means for the first time, of objectively monitoring designated, developed campsites where it is inappropriate to judge impacts against an undisturbed control.
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43

Glen, Morag. "Genetic variation in ectomycorrhizal fungi and its exploitation in ecological investigations of eucalypt forests". Thesis, Glen, Morag (2001) Genetic variation in ectomycorrhizal fungi and its exploitation in ecological investigations of eucalypt forests. PhD thesis, Murdoch University, 2001. https://researchrepository.murdoch.edu.au/id/eprint/51845/.

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Australian eucalypt forests have extremely high species richness and taxonomic diversity of ectomycorrhizal fungi which are root symbionts. Molecular techniques have the potential to distinguish the species present as root associations. PCR-RFLP (polymerase chain reaction - restriction fragment length polymorphism) has been useful in northern hemisphere ecosystems, but further development was needed for Australian taxa. Primers and conditions were optimised for the specific amplification of basidiomycete DNA. RFLP analysis of the amplified fragments distinguished 96 of 109 species of ectomycorrhizal fungi from a study site in the jarrah (Eucalyptus marginata) forest, though some difficulties arose in the Cortinariaceae. In addition, intraspecific variation occurred in a large proportion of the species for which multiple collections were tested. The PCR-RFLP profiles from identified sporocarps were stored in a database to facilitate identification of fungal species colonising ectomycorrhiza. The basidiomycete ectomycorrhizal fungal communities of two adjacent forest blocks with different management histories were characterised by PCR-RFLP analysis. Both blocks had a high degree of biodiversity in the ectomycorrhizal fungal communities. Fourteen taxa, including the most abundant species on each of the blocks, were identified by reference to the database of PCR-RFLP profiles from sporocarps. Another 135 PCR-RFLP profiles from root-tips were not matched to profiles from sporocarps. These profiles were probably caused by species which had not been sampled as basidiomes, implying that species richness is even greater than has been estimated from sporocarp surveys. There was a considerable difference between the blocks in the predominant fungal species. The most common and abundant ectomycorrhizal fungus on block A, which has remained unburnt for the last 66 years, was Russula clelandii. This species was not detected on root tips from block P, which has been burnt every 5-6 years during the last 66 years. Conversely, the most commonly found species on block P, Amanita xanthocephala, was found in very low abundance in only two soil cores from block A. The second most abundant fungus on block A was not matched to the database of PCR-RFLP profiles from sporocarps, and the ITS sequence did not retrieve a close match from searches of Genbank. EMBL or private DNA databases. As the species delimitation of R. clelandii is not clearly defined and collections show a wide range of morphological characters, DNA sequences of collections from across Australia of R. clelandii and two other red-capped Russula species were analysed. In comparison to the level of intraspecific variation seen in other species, a surprising degree of sequence variation among the R. clelandii collections was found, but with no sub-specific grouping which would permit separation of taxa. This is congruent with morphological characters which also show a high degree of variation without unambiguous groups. R. clelandii appears to be a species complex with a very high level of genetic variation.
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Yang, Dongsheng. "The response of two eucalypt subspecies to water stress and fertilizer at early seedling stage". Thesis, Canberra, ACT : The Australian National University, 1987. http://hdl.handle.net/1885/140223.

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Rocha, Julenice Bonifácio de Oliveira. "Diagnose nutricional de plantios jovens de eucalipto na região litorânea do Espírito Santo e sul da Bahia". Universidade Federal de Viçosa, 2008. http://locus.ufv.br/handle/123456789/5402.

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The survival and the success of eucalypt plantations depend on the proper use the soil preparation techniques, of the weed control, of the selection of genetic materials and of the fertilization. Among the factors responsible for the growth of eucalypt plantations there is the mineral nutrition. The consequences of inadequate nutrition will be a smaller growth of the trees especially in their beginning stages until the cutting age, with losses in the final productivity. The results of foliar chemical analyses of young plantations adequately interpreted allow the nutritional diagnosis for eventual corrections on the fertilization, contributing to a better growth of the plants. Thus, the main objective of this study are as follows: to establish rules for the use in methods that evaluate the balance (Kenworthy) and the nutritional equilibrium (DRIS) of young eucalypt stands in the coastal region of the Espírito Santo State and South of the Bahia State, Brazil, checking the influence of the cultivation region of the planting period, and of the genetic material within the values of these rules; to compare the result of the diagnoses between the methods Kenworthy (KW) and the DRIS and among specific and general rules, to check their universality; and to identify and to hierarchize the nutritional limitations in these stands. Data used were from the foliar analyses of eucalypt stands of the Arcel S.A., sampled at six months of age. The reference population was composed by stands of plants that had a height greater than the average + 0.4 standard deviation, at six months of age, and that with a high productivity at three years. It was concluded that the cultivation region, the planting time and the genetic material influence the rule values and the diagnosis of nutritional status of young plantations; that the KW methods was insufficiently sensitive to evaluate the nutritional status for nutrients with high variability of the rules; and that the most limitant nutrients of the plantations studied were Ca, Cu and Mn for the locality of Aracruz; Cu, Mn and Ca for São Mateus; and B, Mg and Mn for the south of Bahia.
A sobrevivência e o sucesso de plantios de eucalipto dependem do uso adequado das técnicas de preparo do solo, do controle de plantas infestantes, da seleção de materiais genéticos e da adubação. Dentre os fatores responsáveis pelo crescimento de plantios de eucalipto está a nutrição mineral. A nutrição inadequada terá como conseqüência o menor crescimento das árvores já nos estádios iniciais, até a idade de corte, com perdas na produtividade final. Os resultados de análises químicas foliares de plantios jovens devidamente interpretados possibilitam o diagnóstico nutricional para possíveis correções na adubação, contribuindo para o melhor crescimento das plantas. Neste intuito, este estudo teve como principais objetivos: estabelecer normas para uso em métodos que avaliam o balanço (Kenworthy) e o equilíbrio nutricional (DRIS) de povoamentos jovens de eucalipto, na região litorânea do Espírito Santo e sul da Bahia, verificando a influência da região de cultivo, da época de plantio e do material genético nos valores dessas normas; comparar o resultado dos diagnósticos entre os métodos Kenworthy (KW) e DRIS e entre normas específicas e gerais, para verificar a sua universalidade; e identificar e hierarquizar limitações nutricionais nesses povoamentos. Os dados utilizados foram provenientes de análise foliar de povoamentos de eucalipto da Arcel S.A., amostrados aos seis meses. A população de referência foi composta por talhões com plantas cuja altura era maior que a média + 0,4 desvio-padrão, aos seis meses de idade, e que tivessem alta produtividade aos três anos. Conclui-se que a região de cultivo, a época de plantio e o material genético influenciam os valores das normas e o diagnóstico do estado nutricional de plantios jovens; que o método KW foi pouco sensível em avaliar o estado nutricional para nutrientes com elevadas variabilidades das normas; e que os nutrientes mais limitantes nos plantios estudados foram Ca, Cu e Mn para a localidade de Aracruz, Cu, Mn e Ca para São Mateus e B, Mg e Mn para o sul da Bahia.
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Fernandes, Loane Vaz. "Normas e determinação de faixas de suficiência para diagnose foliar com base no crescimento relativo de eucalipto". Universidade Federal de Viçosa, 2010. http://locus.ufv.br/handle/123456789/5440.

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The eucalyptus plantations in Brazil cover 4.3 Mha of which 22% is in the state of Sao Paulo. Several studies conclude that there is close and positive correlation between nutrient content and eucalyptus growth rate, and nutrient contents in the leaves reflect the flow of water and nutrients in the soil and correlate with productivity. Thus, the nutritional diagnosis based on tissue analysis can be used as a complementary tool to soil analysis to support crop nutritional management. Among the existing methods of plant nutrient diagnosis, that proposed by Kenworthy (KW) evaluates the balance of nutrients, considering each nutrient individually and the variability of nutrient content in the reference population. On the other hand, the Integrated Diagnosis and Recommendation (DRIS), proposed by Beaufils, evaluates the nutrient equilibrium through the ratio between nutrients. For both it is necessary to construct a set of nutrient standards. The objectives of this work were 1) to obtain standards for KW and DRIS methods, applicable to the diagnosis of nutritional status, based on foliar analysis of young eucalyptus plantations in the state of São Paulo, Brazil; 2) to evaluate the degree of universality of the norms or standards and diagnosis; 3) to evaluate the influence of excluding one or more nutrients showing high contents and high variability in their contents on the diagnosis and on the equilibrium of other nutrients; 4) to develop an alternative method with high biologic meaning, for the definition of sufficiency ranges for the KW and DRIS indexes; 5) to contribute to the improvement of the software NUTREELYPTUS, for leaf nutrient diagnosis. We used database from 1,150 plots of young eucalyptus plantations from which leaves were collected for analysis. The available information included N, P, K, Ca, Mg, S, Cu, Fe, Zn, Mn, and B contents and tree stem height. This stratification was performed by determining the reference population, for which height was greater than average height. We calculated specific (by age and region of cultivation, genetic material, previous crop and textural class) and general (by forest company and for the state of São Paulo) sets of standards. Specific standards were compared with those taken as general standards for each situation by the t test for means and F test for variances. Then, using NUTREELYPTUS, parameterized with these standards (specific and general) and ranges of sufficiency, we obtained the diagnosis of the nutritional status of plantations showing low productivity considering the balance sheet (KW indexes) and equilibrium (DRIS indexes and Potential Response to Fertilization - PRA classes), which were compared, at plot level, based on the frequency of concordant diagnostics (FDC). We used the methods of the Boundary Region (BR) and Mathematics Relative Chance (ChMR) to obtain reference values with greater biological significance. Relevant sets of specific standards were obtained for the diagnosis of nutritional status of young eucalyptus plantations in São Paulo State. The degree of universality of KW and DRIS norms varies with the parameter used (mean, variance, or both together) and, independently of the parameter, is smaller than that of diagnostics made using these standards. For a given company, the high values of FDC allow general standards to be used. Excluding Fe and Mn, nutrients for which the average overall contents were elevated and the variability highest, increases the sensitivity of the diagnostic of nutritional equilibrium, but do not change the degree of universality of the diagnoses made. The KW and DRIS indexes obtained by BF and ChMR can be utilized to obtain the limits of sufficiency ranges with greater biological meaning, seeking the interpretation of foliar analyses. The use of these new limits of sufficiency ranges has little effect on the FDC obtained with specific or general standards. For assessing the nutritional status of young eucalyptus plantations it is recommended to use the limits of sufficiency ranges of KW and DRIS obtained by ChMR method, as proposed in this research. Further studies are needed in order to correlate the nutritional status of young eucalyptus plantations to yield at the harvest age.
Os plantios com eucalipto no país ocupam 4,3 megahectares, dos quais 22 % encontram-se no estado de São Paulo. Diversos trabalhos concluem que há correlação positiva e estreita entre acúmulo de nutrientes e taxa de crescimento do eucalipto, e que os teores de nutrientes nas folhas refletem os fluxos de água e nutrientes no sistema e se correlacionam com a produtividade. Assim, a diagnose nutricional com base em análise de tecido pode ser utilizada como ferramenta complementar à análise de solo para subsidiar o manejo nutricional das culturas. Dos métodos de diagnose existentes, o proposto por Kenworthy (KW) avalia o balanço, considerando os nutrientes de forma individual além de incorporar a variabilidade do teor na população de referência. Já o Sistema Integrado de Diagnose e Recomendação (DRIS), proposto por Beaufils, avalia o equilíbrio nutricional por meio de relações entre os nutrientes. Para ambos há necessidade de se dispor de valores de referência, ou seja, de normas. Os objetivos deste trabalho foram: 1) obter normas para os métodos KW e DRIS, aplicáveis à diagnose do estado nutricional, com base em análise foliar, de plantios jovens de eucalipto no Estado de São Paulo; 2) avaliar o grau de universalidade das normas e dos diagnósticos; 3) avaliar a influência da exclusão de nutrientes cujas normas apresentam altos teores e variabilidade sobre a diagnose, quanto ao equilíbrio, dos demais nutrientes; 4) desenvolver método alternativo, com enfoque mais biológico, para a definição das faixas de suficiência para KW e DRIS; 5) contribuir para a parametrização e aprimoramento do aplicativo computacional NUTREELYPTUS. Foi utilizado banco de dados de análises foliares de 1.150 talhões de plantios jovens de eucalipto, em áreas de duas empresas, contendo informações referentes aos teores de N, P, K, Ca, Mg, S, Cu, Fe, Zn, Mn e B e produtividade. Foi realizada a estratificação deste, determinando a população de referência, cuja altura era maior que a altura média. Foram calculados conjuntos de normas específicas (por época e região de plantio, material genético, cultura antecessora e classe textural), e gerais (por Empresa e para o estado de São Paulo). As normas específicas foram comparadas com as normas tidas como gerais para cada situação, mediante o teste t para as médias e o teste F para as variâncias. A seguir, com o auxílio do NUTREELYPTUS, parametrizado com essas normas (específicas e gerais) e faixas de suficiência, foram obtidos os diagnósticos do estado nutricional de plantios de baixa produtividade quanto ao balanço (índices KW) e equilíbrio (índices DRIS e classes de Potencial de Resposta à Adubação - PRA), que foram comparados, em nível de talhão, pela Frequência de Diagnósticos Concordantes (FDC). Foram utilizados os métodos da Região de Fronteira (RF) e da Chance Matemática Relativa (ChMR) para a obtenção de limites das faixas de suficiência com maior significado biológico. Foram obtidos conjuntos de normas específicas e normas gerais úteis à diagnose do estado nutricional de plantios jovens de eucalipto no estado de São Paulo. O grau de universalidade das normas KW e DRIS varia conforme o parâmetro usado (média, variância ou ambas conjuntamente) e independente do parâmetro é menor do que o dos diagnósticos produzidos com o uso destas normas. Numa mesma empresa, os altos valores de FDC permitem que normas gerais sejam utilizadas. A exclusão de Fe e Mn, nutrientes cujas médias em geral apresentaram-se elevadas e com as maiores variabilidades, aumenta a sensibilidade dos diagnósticos quanto ao equilíbrio nutricional, mas não altera de modo relevante o grau de universalidade dos diagnósticos produzidos. Os métodos RF e ChMR podem ser utilizados visando à obtenção dos limites das faixas de suficiência com maior significado biológico, visando à interpretação de índices KW e DRIS. A utilização desses novos limites de faixas de suficiência pouco alterou a FDC obtidos com normas específicas ou gerais. Para a avaliação do estado nutricional de plantios jovens de eucalipto recomenda-se a utilização dos limites das faixas de suficiência KW e DRIS como proposto neste trabalho pelo método ChMR. São necessários estudos adicionais de modo a correlacionar o estado nutricional de plantios jovens de eucalipto com a produtividade na idade de corte.
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Barbour, Robert Charles. "Gene flow from introduced Eucalyptus plantations into native eucalypt species /". 2003. http://adt.lib.utas.edu.au/public/adt-TU20041207.122154.

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48

Barbour, RC. "Gene flow from introduced Eucalyptus plantations into native eucalypt species". Thesis, 2004. https://eprints.utas.edu.au/237/1/01front.pdf.

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There has been a massive expansion of Eucalyptus plantations in Australia in the last decade. As most eucalypt species are native to Australia, this has raised concerns about genetic pollution of native species gene pools. To assess the risk of genetic pollution, five key aspects of gene flow from E. nitens plantations in Tasmania were studied. Firstly, the pattern of pollen dispersal from plantations into native E. ovata forests was examined at three sites. The frequency of F1 hybrids among 119 000 progeny, grown from open-pollinated seed collected from E. ovata trees at varying distances from E. nitens plantations, was determined. A leptokurtic pattern of pollen flow was evident, with the mean level of hybridisation at the plantation boundaries (0-100 m) being 14%, dropping to 1% by 200-300 m and continuing at this level to the extent of the studied areas (max. 1600 m). Secondly, the first exotic E. ovata x nitens F1 hybrids actually established in the wild were discovered and verified using morphological and allozyme analyses. Thirdly, field trials were established to assess the fitness of the exotic E. ovata x nitens F1 hybrids in the wild. The hybrids displayed poorer early-age performance relative to their pure E. ovata half-sibs. However, many were still alive and growing successfully two years after planting. Fourthly, surveys of flowering time were conducted on native Symphyomyrtus species, which were potentially at risk of gene flow from plantations. This was combined with a spatial analysis of the proximity of eucalypt plantations to each native species, and used to produce an overall assessment of the potential for exotic hybridisation and gene flow. These results indicated that at least eight of the 16 Symphyomyrtus species in Tasmania appear to have significant potential for pollination by E. nitens, and will need further study. Finally, the crossability of E. nitens pollen on native female Symphyomyrtus species was assessed using artificial pollination techniques. A number of species did not produce hybrids with E. nitens, indicating that post-mating barriers may be acting to prevent hybridisation. Overall results suggest that the main risk of genetic pollution in Tasmania is limited to a few species. Of those species, the ability of first and later generation hybrids to survive to reproductive maturity and backcross with native populations, allowing the introgression of exotic genes, is yet to be assessed.
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49

Barbour, RC. "Gene flow from introduced Eucalyptus plantations into native eucalypt species". 2004. http://eprints.utas.edu.au/237.

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There has been a massive expansion of Eucalyptus plantations in Australia in the last decade. As most eucalypt species are native to Australia, this has raised concerns about genetic pollution of native species gene pools. To assess the risk of genetic pollution, five key aspects of gene flow from E. nitens plantations in Tasmania were studied. Firstly, the pattern of pollen dispersal from plantations into native E. ovata forests was examined at three sites. The frequency of F1 hybrids among 119 000 progeny, grown from open-pollinated seed collected from E. ovata trees at varying distances from E. nitens plantations, was determined. A leptokurtic pattern of pollen flow was evident, with the mean level of hybridisation at the plantation boundaries (0-100 m) being 14%, dropping to 1% by 200-300 m and continuing at this level to the extent of the studied areas (max. 1600 m). Secondly, the first exotic E. ovata x nitens F1 hybrids actually established in the wild were discovered and verified using morphological and allozyme analyses. Thirdly, field trials were established to assess the fitness of the exotic E. ovata x nitens F1 hybrids in the wild. The hybrids displayed poorer early-age performance relative to their pure E. ovata half-sibs. However, many were still alive and growing successfully two years after planting. Fourthly, surveys of flowering time were conducted on native Symphyomyrtus species, which were potentially at risk of gene flow from plantations. This was combined with a spatial analysis of the proximity of eucalypt plantations to each native species, and used to produce an overall assessment of the potential for exotic hybridisation and gene flow. These results indicated that at least eight of the 16 Symphyomyrtus species in Tasmania appear to have significant potential for pollination by E. nitens, and will need further study. Finally, the crossability of E. nitens pollen on native female Symphyomyrtus species was assessed using artificial pollination techniques. A number of species did not produce hybrids with E. nitens, indicating that post-mating barriers may be acting to prevent hybridisation. Overall results suggest that the main risk of genetic pollution in Tasmania is limited to a few species. Of those species, the ability of first and later generation hybrids to survive to reproductive maturity and backcross with native populations, allowing the introgression of exotic genes, is yet to be assessed.
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50

Horton, BM. "Eucalypt decline and ectomycorrhizal fungal community ecology of Eucalyptus delegatensis forest, Tasmania, Australia". Thesis, 2011. https://eprints.utas.edu.au/12468/2/Horton_PhD_Thesis_FINAL_041111.pdf.

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Ectomycorrhizal fungi underpin critical ecosystem processes which affect tree health. Eucalypt decline is widespread throughout Australia, and its cause has been attributed to a variety of factors, including forest management. In Tasmania, dieback in Eucalyptus delegatensis R.T. Baker has been linked to altered fire regimes and associated changes in mycorrhizal communities. This thesis presents a study that explores ectomycorrhizal species richness and community composition in relation to eucalypt health, understorey vegetation and soil chemistry in the context of fire history. The results further our understanding of ectomycorrhizal ecology and elucidate factors important to the maintenance of a healthy forest ecosystem. Study sites were established in E. delegatensis forest with either sclerophyll understorey (six plots) or rainforest understorey (six plots). Eight of the plots, located in north-east Tasmania, had been established for a study of fire ecology and had known fire histories ranging from 42 years since the last fire to long unburnt (>120 years). Four plots located in north-western Tasmania were long unburnt but had been disturbed by logging 22-25 years previously. Ectomycorrhizal fungal sporocarps, root tips and soil samples were collected during a three-year period from all 12 plots. Samples from soil, root tips and sporocarps gave rise to different but complementary information about ectomycorrhizal communities. Fungal operational taxonomic units were identified through DNA sequencing and phylogenetic analysis. At each site, understorey vegetation was characterised, soil and eucalypt foliage chemistry was analysed, and eucalypt crown condition was assessed. Primary crown dieback was identified as the most effective method for the measurement of eucalypt health. Multivariate statistical analyses were used to explore the relationships among ectomycorrhizal communities, eucalypt health, vegetation and abiotic variables. E. delegatensis forest with rainforest understorey was more than likely to be affected by severe eucalypt decline, had higher concentrations of soil inorganic nitrogen (nitrate and ammonium) and eucalypt foliar nitrogen, and had lower concentrations of soil and eucalypt foliar phosphorus, than forest with sclerophyll understorey. As forest declined in health the ecosystem moved from being nitrogen limiting to phosphorus limiting due to reduced phosphorus availability and plant uptake, potentially due to altered mycorrhizal activity. Ectomycorrhizal communities differed between moderately and severely declining forest and were correlated to crown health and altered soil chemistry associated with the two levels of decline. The Cortinariaceae had high species richness in healthiest sites while the Russulaceae and Thelephoraceae were rich in forest affected by severe decline. In northwestern and north-eastern Tasmania unique and distinctly different ectomycorrhizal fungal communities were found to occur in E. delegatensis forest with rainforest understorey versus those with sclerophyll understorey. Irrespective of understorey type and health status, the Cortinariaceae were highly diverse, and were the most species-rich family within the ectomycorrhizal community of E. delegatensis forest. The Cortinariaceae also was the most abundant family in the root tip community. The Helotiales, Russulaceae and Thelephoraceae also were important components. The importance of the Cortinariaceae in E. delegatensis forest is similar to other Australian eucalypt forests but distinctly different from northern hemisphere forests, which tend to be dominated by the Russulaceae, Thelephoraceae and Corticeaceae. Distance-based multiple linear regression models using only significant predictor variables based on soil and foliage nutrient concentrations and crown health were able to explain 52% of the variation in fungal community composition, and 44% of the variation in ectomycorrhizal community proportional composition at the family level. Soil pH, total soil nitrate, soil organic carbon and soil phosphorus were significant in predicting ectomycorrhizal species composition and proportional composition in the final models. A multiple linear regression model showed that available soil nitrate and phosphorus were significant in predicting ectomycorrhizal community richness. High richness was associated with low available soil nitrate or phosphorus. Northern hemisphere studies which show that changes in soil chemistry, especially mineral nitrogen, can strongly influence mycorrhizal species richness, species composition and community structure corroborate the likely influence of soil nitrogen on the ectomycorrhizal communities of E. delegatensis forest. This is the first study to find a strong correlation between ectomycorrhizal fungal communities and the status of eucalypt forest health. The results support the currently proposed model that, in the absence of fire, premature decline of temperate Australian eucalypt forests is closely linked to changes in soil chemistry, understorey vegetation and mycorrhizal communities.
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