Rozprawy doktorskie: „Litterfall”

1

Thomas, Raquel Simone. "Forest productivity and resource availability in lowland tropical forests in Guyana". Thesis, University of London, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325358.

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2

Zhang, Ping. "Nutrient inputs from trees via throughfall, stemflow and litterfall in an intercropping system". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0003/MQ43241.pdf.

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3

Martinez-Sanchez, Jose Luis. "Aspects of rain forest nutrition dynamics at Los Tuxtlas, Mexico". Thesis, University of Stirling, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311704.

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4

Firmino, Paulo Neves. "Análise do módulo da queda de folhada em eucaliptais no modelo 3-PG". Master's thesis, ISA/UTL, 2011. http://hdl.handle.net/10400.5/3946.

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Mestrado em Engenharia Florestal e dos Recursos Naturais - Instituto Superior de Agronomia
An underestimation of accumulated leaf biomass obtained with the 3-PG model when applied to a fertilization and irrigation trial of Eucalyptus globulus, conduced to install three plots in seminal high forest of Eucalyptus globulus with different ages and different site indexes to support the tendency observed in the fertilization and irrigation trial. Plots 1 and 2 were installed in a 4,5 years old eucalyptus stand, while plot 3 was installed in a 8,5 years old stand. Acummulated litterfall (dried) biomass during the period 15 March – 26 October 2011, was 1,12 Mg ha-1, 1,86 Mg ha-1 e 2,82 Mg ha-1 respectively. A higher site index distinguished results of the same age stands, while the plot at the older stand achieved superior biomass. Although the reduced number of litterfall collects, estimates obtained by 3-PG when applied to the three plots confirm the underestimation of litterfall. It’s necessary to complete this study for at least one year and possibly install more plots in different combinations of age and site index to confirm the need of improvement of the litterfall module of 3-PG model in Portugal.

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5

Oelbermann, Maren. "Litterfall and nutrient fluxes across the terrestrial-aquatic ecotone in a rehabilitated riparian environment". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0004/MQ43193.pdf.

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6

Coelho, Joaquim Matheus Santiago. "Serrapilheira aplicada como biomonitor na avaliação do bosque urbano do Instituto de Pesquisas Energéticas e Nucleares, São Paulo,SP". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/85/85134/tde-24082012-162944/.

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Diversos processos são considerados responsáveis pela manutenção de ecossistemas. Entre eles podemos destacar a ciclagem mineral que corresponde ao ciclo dos elementos químicos que fluem entre os compartimentos bióticos, folhas e serrapilheira, e abióticos, atmosfera e solo. Esses elementos químicos se acumulam de forma ativa via absorção nos tecidos desses organismos, possibilitando sua aplicação como biomonitor na avaliação da qualidade do ambiente. Partindo dessa premissa é possível, a partir do estudo de ciclagem bioquímica de serrapilheira, conhecer a proveniência dos elementos químicos observados nas folhas diagnose das árvores. Este trabalho teve como objetivo avaliar, em escala espacial e temporal, as características da produção e sazonalidade da deposição da serrapilheira bem como estudar a composição química das folhas originadas desta serrapilheira depositada no campus do Instituto de Pesquisas Energéticas e Nucleares, IPEN, São Paulo, (RMSP) visando seu emprego como indicador do estagio de conservação ou degradação das áreas estudadas. Foram instalados 10 coletores de serrapilheira, com as dimensões de 1m x 1m, profundidade de 45 cm e 2 mm de malha, dispostos a 20 cm do solo sob a copa das árvores. Para determinação da produção de serrapilheira foram recolhidas deposições mensais nos coletores entre os meses: Fevereiro/2010 à Janeiro/2011. A determinação dos elementos químicos foi realizada utilizando as técnicas de fluorescência de raios-X por dispersão de comprimento de onda (WDXRF) e espectrometria de emissão ótica com fonte de plasma de argônio induzido (ICP-OES). Para a análise estatística dos dados foi aplicada a análise de componentes principais. A heterogeneidade temporal observada foi conseqüência da sazonalidade, interferindo na produção de serrapilheira em relação à quantidade e às porcentagens das frações. A produção de serrapilheira (base seca) durante o período de desenvolvimento da pesquisa foi de 5,86 Kg m-2 ano-1 sendo a espécie Psidiumguajara com maior índice de serrapilheira. Entre as frações, o compartimento folhas foi o mais representativo com 53,12% seguido do compartimento madeira com 26,84% e das partes reprodutivas que representou 20,04% de toda serrapilheira. Os elementos analisados foram Ca, Si, K, P, Fe Cl, Ni, Sr, Zn, Cu, Th, U, Mn, Al, Ti, Na, Mg, S e Br. Os elementos mais abundantes foram Ca, Si e K (1,8%, 0,5% e 0,6%, respectivamente) representando a composição foliar. Apesar de no passado ter havido unidades piloto de purificação de urânio e de tório, bem como considerando as atuais instalações do ciclo do combustível, foi observado que o material monitorado não se apresentou impactado quanto aos elementos químicos avaliados, e as instalações existentes não afetaram o ciclo biogeoquímico das plantas. O estudo trouxe resultados extremamente relevantes para se entender melhor em que estado se encontra o bosque em torno das instalações nucleares do IPEN/SP.
Several processes are considered responsible for ecosystems maintaining. Among them we can highlight mineral cycling that corresponds to the cycle of chemical elements that flow between the biotic compartments, leaves and litterfall, and abiotic, atmosphere and soil. These chemical elements accumulate of the active form through the absorption in the tissues of these organisms, allowing its use as a use as biomonitor in the environment quality evaluation. Based on this premise it is possible, from the biochemical cycling study of litterfall, to know the origin of chemical elements observed in diagnosis leaves of trees. The objective of this study was evaluate, on spatial and temporal scale, the characteristics of the production and seasonality of the litterfall deposition and study the chemical composition of leaves arising from this litterfall deposited on the campus of the Nuclear and Energy Research Institute IPEN, São Paulo (RMSP), aiming the employment as an indicator of the conservation or degradation stage of the studies areas. Were installed 10 litterfall collectors, measuring 1m², depth of 45 cm and 2 mm mesh, placed at 20 cm from soil under the crown of 10 trees. To determinate the production of litterfall was collected the deposition monthly during the months of February/2010 through January/2011. The determination of chemical elements was realized by X-ray fluorescence for dispersion of wavelength (WDXRF) and inductively coupled plasma optical emission spectroscopy (ICP-OES). For the statistical analysis was applied to principal component analysis. The temporal heterogeneity observed was consequence of seasonality, interfering in the litterfall production relative to the amount and percentages of fractions. The production of litterfall (dry basis), during the development of the research was 5.86 kg m² year-1, being the Psidiumguajava species with the highest litterfall rate. Among the fractions, the most representative compartment was leaves with 53.12%, followed by wood with 26.84% and reproductive parts thats represented 20.04%, of all litterfall. The elements analyzed were Ca, Si, K, P, Fe Cl, Ni, Sr, Zn, Cu, Th, U, Mn, Al, Ti, Na, Mg, S e Br. The most abundant were Ca, Si, and K (1.8%, 0.5% and 0.6 respectively) representing the leaf composition. Although in the past have been pilot units of uranium and thorium purification, as well considering the current fuel cycle installations, it was observed that monitored material not be presented impacted as to the chemical elements evaluated, and the installations existing do not affect the biogeochemical cycle of plants. The study brought highly relevant results to better understand in what state is the forest around the nuclear facilities of IPEN/SP.

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7

Acker, Marty. "Base cation concentration and content in litterfall and woody debris across a northern hardwood forest chronosequence". Lexington, Ky. : [University of Kentucky Libraries], 2006. http://lib.uky.edu/ETD/ukyfore2006t00460/Acker.pdf.

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Thesis (M.S.)--University of Kentucky, 2006.
Title from document title page (viewed on August 22, 2006). Document formatted into pages; contains: vi, 79 p. : ill. Includes abstract and vita. Includes bibliographical references (p. 71-78).

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8

Acker, Marty. "BASE CATION CONCNETRATION AND CONTENT IN LITTERFALL AND WOODY DEBRIS ACROSS A NORTHERN HARDWOOD FOREST CHRONOSEQUENCE". UKnowledge, 2006. http://uknowledge.uky.edu/gradschool_theses/286.

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Forest floor calcium (Ca) declines in northern hardwood forests are of interest because Ca availability may limit future forest growth. In the 1990s investigations into Ca pools and fluxes across a northern hardwood forest chronosequence showed decreases across stand age in the mass of forest floor base cations and litterfall cation concentrations. I undertook a study of factors that influence litterfall chemistry to develop a better understanding of base cation biogeochemistry in developing northern hardwood forests. Although Ca, potassium (K), and magnesium (Mg) concentrations in litterfall significantly declined with stand age, species composition and soil nutrient availability also influenced litterfall chemistry. The interplay between these factors, such as the distribution of species with different nutrient demands in areas of base cation availability or limitation, influences forest floor chemistry and may impact the time in which soil Ca depletion occurs. Additionally, I examined the quantity and qualities (species composition, decay class, size, and nutrient concentrations and contents) of woody debris across the same northern hardwood forest chronosequence. The objectives of this study were to quantify cation pools in woody debris, describe how the qualities of these woody debris pools change with stand development, and establish a baseline for long-term measurements of woody debris accumulation and chemistry with stand age. Decomposition of woody debris transfers base cations to the forest floor, and may be partially responsible for forest floor Ca gains in young stands. Calcium and K pools in woody debris were most strongly influenced by woody debris biomass, whereas Mg content was influenced by both woody debris biomass and species composition. In young stands, woody debris pools were strongly influenced by management practices during harvest. By 20 years since harvest woody debris pools reflected processes of stand development. For example, from 20 to nearly 40 years since harvest woody debris biomass and species composition was dominated by mortality of early successional species. Woody debris in more mature stands reflected small-scale stochastic disturbances including disease and single-tree mortality. Litterfall and woody debris are each components of within-stand cation cycling that will be critical to future forest growth with limited Ca availability.

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9

Morris, David Michael. "Biogeochemical cycling of macroelements in black spruce (Picea mariana (Mill.) B.S.P.) ecosystems, quantifying precipitation and litterfall fluxes". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0022/NQ51042.pdf.

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10

SANTOS, AGNI HEVEA DOS. "LANDSCAPE TRANSFORMATION OF AN URBAN FOREST IN PEDRA BRANCA MASSIF: THE LITTERFALL AS A TOOL OF ANALYSIS". PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2009. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=33004@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
A compreensão da estrutura e funcionalidades ecológicas inscritas na transformação da Mata Atlântica fluminense, compreendida por fragmentos florestais em meio à crescente urbanização, são de suma importância ao entendimento do conteúdo da paisagem via história ambiental e ecologia da paisagem. A complexidade ambiental característica da contemporaneidade geográfica instaura a coadunação de diversas abordagens tanto epistemológicas quanto metodológicas na apreensão da paisagem enquanto mosaico e resultante das multiescalares intervenções de seus elementos fundantes: estruturais e funcionais. Tais elementos encontram-se estabelecidos sob diferenciadas condições devido à orientação da encosta –vertentes soalheiras e Noruega - apresentam níveis de umidade, temperatura e precipitações diferenciadas em até 160 porcento. O estudo utiliza os parâmetros e métodos de análise ambientais como: fitossociologia, físico-química do solo, aporte, decomposição e retenção hídrica de serrapilheira na compreensão da resultante ecológica das distintas orientações e sítios topográficos. Para tanto a influência de tais variáveis na produtividade florestal foram analisadas utilizando-se 12 coletores de serrapilheira no sítio amostral da bacia do Camorim – sítio St. Agostinho, relancionando-os aos dados de pluviosidade da estação meteorológica do Riocentro (GEORIO). Foram realizadas coletas quinzenais para a produção e trimestrais para o estoque de serrapilheira durante um ano. A produção de serrapilheira na orientação NE (bacia do Camorim) foi de 10.733,80 kg.ha.ano-1 e superior em relação à orientação SW no mesmo período (Bacia do Caçambe), com 9.463,88 kg.ha.ano-1, sendo a fração folhas preponderante às demais. Os resultados sugerem a influência tanto dos usos pretéritos – legado dos carvoeiros, quilombolas e agricultores tradicionais – quanto das variáveis ecológicas – orientação de encosta, sítio topográfico, precipitação e a condição vegetacional da floresta atlântica, etc. Entretanto, os limites analíticos vão além da impossibilidade de generalizar e simplificar a paisagem. As imprecisões científicas – comuns aos diversos campos epistemológicos – inscrevem-se na abordagem co-evolutiva ao apontar os desafios da padronização e modelagem da paisagem. A transformação da Mata Atlântica mesmo que no recorte espacial (bacias do Camorim e Caçambe) adotado, não é passível de simplificação analítica e os resultados obtidos confirmam tais limitações.
The comprehension of the ecological structure and functions wrote by transformation of Atlantic Rainforest, understood as forest fragments involved by rising urbanization, is of basic importance in the understanding of the landscape by Environmental History and Landscape Ecology. The characteristically environmental complexity of the contemporary Geography settles the approaches convergence both epistemological as methodological in the landscape understandings, so as a patch and as a resultant of the multiscalar actions of their foundations elements: structurals and functionals ones. These elements are found under different conditions due to slope aspect – with different humidity, temperature and rainfall almost as 160 percent in the north slope. The currently study uses some parameters and environmental analysis as: phytosociology, soil phical-chemestry and litterfall production, decomposition and hydrological retention capacity in the understanding of the ecological resultants of the different orientation and topographic sites – soalheira and noruega slope. To investigate the influence of these variables on the forest productivity the litter dynamics were analyzed employing 12 littertraps randomly distributed at the sample site in Camorim basin – St. Agostinho site, and investigating the relation between pluviosity regime using rainfall data from GEORIO Metereological Station of Riocentro. The samples were collected at each 15 days for litter production and at three months for litter stock during one year. The litter production at NE aspect (Camorim Basin) was 10.733,80 kg.ha.ano-1 and greater than that found at Caçambe Basin (SW) - 9.463,88 kg.ha.ano-1, with leaf fraction greater than the others. The results suggest that the past uses - environmental legacy of the use of the coal collectors, quilombolas and traditional agriculture – and the ecological variables – slope aspects, topographic sites, precipitation, and rainforest vegetal condition etc. Despite that, the analytical limits bypass the impossibilities of landscape simplification. The science inaccuracies – common to all epistemological science areas – are written on the coevolutive approache when shows the challenges of landscape standardization and modeling. The rainforest transformation, even in the case of a well known adopted area (Camorim and Caçambe basins), were not easy to an analytical simplification as was demonstrated by the observed results.

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11

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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12

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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13

Rindy, Jenna. "Urban Trees as Sinks for Soot: Deposition of Atmospheric Elemental Carbon to Oak Canopies and Litterfall Flux to Soil". Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1157527/.

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Elemental carbon (EC), a product of incomplete combustion of fossil fuels and biomass, contributes to climate warming and poor air quality. In urban areas, diesel fuel trucks are the main source of EC emissions from mobile sources. After emission, EC is deposited to receptor surfaces via two main pathways: precipitation (wet deposition) and directly as particles (dry deposition). Urban trees may play an important role in removing EC from the atmosphere by intercepting and delivering it directly to the soil. The goal of this research was to quantify the magnitude of EC retention in leaf waxes (in-wax EC) and EC fluxes to the soil via leaf litterfall in the City of Denton, Texas. Denton is a rapidly growing urban location in the Dallas-Fort Worth metropolitan area. A foliar extraction technique was used to determine EC retention in leaf waxes. Foliar samples were collected monthly, from April through July, from pairs of Quercus stellata (post oak, n=10) and Quercus virginiana (live oak, n = 10) trees. Samples were rinsed with water and chloroform in a two-step process to determine EC retained in leaf waxes. A Sunset OC/EC aerosol analyzer was utilized to analyze the EC content of extracts filtered onto quartz-fiber filters. From April through July, leaf litter was collected bi-weekly under 35 trees (20 post oak, 15 live oak), and oven dried to determine dry weight. EC retained by tree canopies was estimated by multiplying in-wax EC by canopy leaf area index, while EC flux to soil was estimated by multiplying in-wax EC by leaf litterfall mass. This study shows that through retention of EC in leaf waxes, urban tree canopies represent important short-term sinks for soot in urban areas.

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Lins, Sílvia Rafaela Machado. "Nutrients dynamics in tropical forest fragments located in an area of Atlantic Forest of the state of Alagoas". Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-17102017-103106/.

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The Northeastern Atlantic Forest of Brazil contains thousands of forest fragments at different stages of regeneration, some recovering from abandoned agricultural fields, while others recovering from chronic disturbances such as fire, logging, and poaching. Some of these fragments kept protected for several reasons: corporate responsibility, compliance with the forest code, preservation of biodiversity, among others. Although these fragments are far from having the same species richness of plant and animal, they can perform important ecosystem services, such as protection of water bodies, reservoir of important nutrients and carbon (C). This is especially important if we consider that there are global initiatives such as REDD + with the objective of assessing secondary forests and forests in recovery process as important C pools. On the other hand, the management and preservation of these fragments depends on a solid knowledge about their structure and nutrient cycle. There is a relatively rich literature on the loss of biodiversity in these Northeastern forest fragments. Much less is available, however, about the structure and function of these fragments. This work intends to contribute to fill this gap, providing solid scientific information on four forest areas and a secondary forest, where a restoration program was implemented in the State of Alagoas, Northeast of Brazil. After a brief introduction, chapter one discusses the structure of these fragments through a complete forest inventory, where individuals density, height and diameter at breast height (DBH) were measured for each tree with DBH >= 10 cm. With these allometric data, we estimated the basal area and aboveground live biomass (AGLB), comparing these attributes with other estimates available in the literature. In chapter two, we investigated the distribution of nutrients in the forest fragments, where we measured the foliar concentration of C, nitrogen (N) and phosphorus (P). At the same time, we measured the litterfall mass in each fragment and its nutrient content for a one year period of sampling. With this information we were able to establish how these areas cycled their main limiting nutrients and C. Finally, in the last chapter we approached the partition of C and nutrient stocks, above and belowground, in order to evaluate the importance of C pools and nutrients in the forest fragments and understand the role of these fragments in a world that urgently needs to store C in a sustainable reservoir.
A Floresta Atlântica do Nordeste do Brasil contém milhares de fragmentos de florestas em diferentes estágios de regeneração, alguns se recuperando de campos agrícolas abandonados, enquanto outros se recuperam de distúrbios crônicos como incêndio, extração de madeira e caça furtiva. Alguns desses fragmentos ficaram protegidos por várias razões: responsabilidade corporativa, cumprimento do código florestal, preservação da biodiversidade, entre outros. Embora estes fragmentos estejam longe de ter a mesma riqueza de espécies vegetais e animais, podem desempenhar importantes serviços ecossistêmicos, como proteção de corpos d\'água, reservatório de importantes nutrientes e carbono. Isso é especialmente importante se considerarmos que há iniciativas globais como o REDD+ que visam avaliar florestas secundárias e de recuperação como importantes reservatórios de carbono (C). Por outro lado, a gestão e preservação destes fragmentos dependem de um conhecimento sólido sobre a sua estrutura e ciclo de nutrientes. Há uma literatura relativamente rica sobre a perda de biodiversidade nestes fragmentos florestais do Nordeste. No entanto, muito menos está disponível sobre a estrutura e o funcionamento destes fragmentos. Este trabalho pretende contribuir para o preenchimento desta lacuna, fornecendo informações científicas sólidas sobre quatro áreas florestais e uma floresta secundária, onde foi implantado um programa de restauração no Estado de Alagoas, Nordeste do Brasil. Após uma breve introdução, o capítulo um discute a estrutura desses fragmentos através de um inventário florestal completo, onde a densidade indivíduos, sua altura e diâmetro à altura do peito (DAP) foram medidos para cada árvore com DAP >= 10 cm. Com esses dados alométricos, estimamos a área basal e a biomassa viva acima do solo (AGLB), comparando esses atributos com outras estimativas disponíveis na literatura. No capítulo dois, investigamos a distribuição de nutrientes nos fragmentos florestais, onde medimos a concentração foliar de C, nitrogênio (N) e fósforo (P). Ao mesmo tempo, medimos durante um ano a massa da serapilheira em cada fragmento e seu teor de nutrientes. Com essas informações pudemos estabelecer como essas áreas ciclam seus principais nutrientes limitantes e C. Finalmente, no último capítulo abordamos a partição dos estoques de C e nutrientes, acima e abaixo do solo, com o objetivo de avaliar a importância dos pools de C e nutrientes nos fragmentos de floresta e entender qual o papel desses fragmentos em um mundo que necessita urgentemente estocar C em um reservatório sustentável.

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Tahmasbian, Iman. "Rapid Assessment and Dynamics of Carbon and Nitrogen Cycling in a Suburban Native Forest Ecosystem in Response to Prescribed Burning". Thesis, Griffith University, 2017. http://hdl.handle.net/10072/378724.

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The risk of wildfire has been increased in Australian forests due to climate change, poor quality of foliage and low rates of herbivory. In response, prescribed burning (PB) is applied, under specified conditions, for reducing the risk of wildfire and protecting the built-up areas by reducing the accumulated forest fuels. The application of PB, however, has shown to affect carbon (C) and nitrogen (N) dynamics in the burned forest ecosystems. For example, concentrations of labile C and N increase after PB due to the improved C and N mineralisation and incorporation of ashes in soils. Repeated burning, however, results in the reduced soil C and N concentrations over the time after PB. Volatilization of C and N from the soil during burning is an important factor decreasing the soil C and N levels in the affected forests. The variations in soil C and N pools influence the plant ecophysiological status, litterfall mass production (LM) and litterfall quality. Although there are studies investigating the effects of PB on soil C and N dynamics in forest ecosystems, the information is still limited about the short- to long- term effects of PB on soil C and N cycling in subtropical urban forests. Hence, a 23- month study was conducted to understand the variations in C and N pools after PB in Toohey Suburban Forest, South-East Queensland, subtropical Australia. Since the measurements of C and N concentrations in soil and plant samples using mass spectroscopy are expensive and time-consuming, the possibility of using hyperspectral image analysis, as a cost-effective and rapid technology, for predicting C and N concentrations in soil and litterfall samples was also investigated. The objectives of this study, addressed in each chapter, were (1) understanding the short- (within the first 12 months) to medium-term (up to 23 months) variations in soil C and N pools after PB using frequent (monthly to every three months) sampling (Chapter 3); (2) investigating the short- to medium-term effects of PB as well as climatic factors on litterfall quantity and quality in the forest ecosystem (Chapter 3); (3) elucidating the mechanisms involved in the short- to medium-term changes in C and N cycling in the forest ecosystem subjected to PB (Chapter 3); and (4) investigating the possibility of using hyperspectral image analysis to predict TC, TN, δ13C and δ15N of the litterfall (Chapters 4) and soil (Chapter 5) as well as C functional group distributions in decomposing litterfall samples (Chapter 6). In Chapter 3, the dynamics of labile C and N pools under the influence of PB in Toohey Forest were investigated. Soil and litterfall samples were collected from two study sites (B0 and B1). The soil and litterfall samplings were commenced at the site B0 from month 1 to month 12 after PB and at the site B1 from month 5 to month 23 after PB. The soil and litterfall samples were collected monthly from month 1 to 6 and then every three months from month 6 to 12 after PB at the site B0. The samples were collected every three months at the site B1 (month 5 to 23 after PB). Soil labile C and N pools, soil C and N isotopic compositions (δ13C and δ15N), litterfall LM, TC, TN, δ13C and δ15N and tree leaf photosynthesis in dry and wet seasons in Eucalyptus Baileyana and Eucalyptus Planchoniana were determined. The gas-exchange measurements were conducted in dry (July 2015) and wet (February 2016) seasons at the site B0. The results indicated that soil labile C and N pools fluctuated within the first 12 months after PB which might be attributed to the incorporation of ashes in the soil and the re- establishment of soil microbial abundance and activity after PB. The highest values of soil δ13C were observed immediately after PB followed by a gradual decrease until end of the experiment. This high δ13C after PB might be due to the addition of ashes with high values of δ13C to the soil. The litterfall δ13C variations were mainly driven by photosynthetic capacity influenced by soil labile N variation after PB and climatic factors (temperature). There were seasonal and interspecies variations in photosynthesis (A1,400) and stomatal conductance (gs) with their higher values observed in the dry season, which might be attributed to the more favourable temperature in the dry season. The LM was also driven by climatic factors (rainfall) and N availability after PB. Overall, soil N availability and climatic factors (rainfall and temperature) were the main driving factors of C and N cycling in the studied forest after PB. In Chapter 4, a visible to near-infrared (400–1700 nm) hyperspectral imaging system was employed to capture the hyperspectral images from the 462 litterfall samples. The spectra extracted from the images were correlated with their corresponding values of litterfall TC, TN, δ13C and δ15N using partial least-square regression (PLSR) models. The wavelengths with higher β coefficient were selected as the most important wavelengths and were used to develop the final models. The final models were, then, tested using an external validation set (90 samples). The results showed that the data of litterfall TC and δ13C could not be fitted to the PLSR model, possibly due to small variations observed in the litterfall TC and δ13C data and low resolution of the cameras (~10 nm). The models, however, were successfully developed to predict litterfall TN (R2 = 0.76; RMSE = 0.50 %) and δ15N (R2 = 0.72; RMSE = 0.98 %). The external validation R2t of the prediction was 0.64 and 0.67, and the RMSEt was 0.53 % and 1.19 ‰, for litterfall TN and δ15N respectively. The ratio of performance to deviation (RPD) of the predictions was 1.48 and 1.53, respectively for litterfall TN and δ15N. The obtained RPDs show that the models were reliable for the prediction of TN and δ15N in the new forest leaf litterfall samples. In Chapters 5 and 6, a hyperspectral camera with higher resolution (~ 1.3 nm) was used in the spectral region of 400–1000 nm to capture hyperspectral images from 120 soil samples and 118 decomposing litterfall samples. In Chapter 5, PLSR models were used to correlate the spectra extracted from the images with their corresponding values of TC, TN, δ13C and δ15N in the soil samples. The wavelengths with higher β coefficient were selected as the informative wavelengths and were used to develop the final models. The developed models provided acceptable predictions with high R2 and low RMSE for soil 93 TC (R2 = 0.82; RMSE = 1.08 %), TN (R2 = 0.87; RMSE = 0.02 %), δ13C (R2 = 0.82; RMSE = 0.27 ‰) and δ15N (R2 = 0.90; RMSE = 0.29 ‰). The prediction abilities of the final models were then evaluated using the spectra of the external test set (24 samples). The models provided acceptable predictions with high R2t and RPD of test set for soil TC 97 (R2t = 0.76; RPD = 2.02), TN (R2t = 0.86; RPD = 2.08), δ13C (R2 = 0.80; RPD = 2.00) and δ15N (R2t = 0.81; RPD = 1.94). The results indicated that the laboratory-based hyperspectral image analysis has the potential to estimate and predict soil TC, TN, δ13C and δ15N. In Chapter 6, the potential of hyperspectral image analysis for predicting C functional group distributions in decomposing litterfall samples was investigated. Particle swarm optimisation (PSO) technique was used to select the most important wavelengths before developing the models. Then PLSR and artificial neural network (ANN) models were used to correlate the most important wavelengths with their corresponding values of C functional group distributions, determined using 13C-NMR spectroscopy, in the calibration data sets (86 samples). The developed models were then validated using the external test sets (21 samples). The results showed high accuracies of prediction of alkyl- 109 C (R2t = 0.72; RPD = 1.86), O,N-alkyl-C (R2t = 0.73; RPD = 1.82), di-O-alkyl-C1 (R2 = 110 0.71; RPD = 1.78), di-O-alkyl-C2 (R2 = 0.74; RPD = 1.71), aryl-C1 (R2t = 0.76; RPD = 1.90), aryl-C2 (R2 = 0.75; RPD = 1.76) and carboxyl derivatives (R2t = 0.63; RPD = 1.43) in the external test sets using PLSR models. The ANN models also successfully predicted 113 O,N-alkyl-C (R2t = 0.62; RPD = 1.54), di-O-alkyl-C1 (R2t = 0.68; RPD = 1.76), di-O-alkyl- 114 C2 (R2t = 0.69; RPD = 1.52), aryl-C1 (R2 = 0.82; RPD = 2.10) and aryl-C2 (R2t = 0.67; RPD = 1.72) in the external test sets. With the exception of aryl-C1, the results indicated more reliable predictions of the C functional group distributions using the PLSR model compared to those of ANN models given the limited amount of training data. Neither the PLSR nor the ANN model was successful in the prediction of the carbohydrate-C and O- aryl-C. Overall, the soil labile C and N and δ13C, were influenced by the incorporation of ashes in the soil after PB. The litterfall quality was mainly influenced by N availability and climatic (seasonal) factors. The hyperspectral image analysis in combination with the PLSR modelling could successfully predict litterfall TN and δ15N, soil TC, TN, δ13C and δ15N and C functional group distributions in the decomposing litterfall samples in Toohey Forest ecosystem under PB.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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McConnell, Steven P. "Effects of gypsy moth defoliation on acorn production and viability, litterfall, and litter layer depth and biomass in north-central Virginia and western Maryland". Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/45883.

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The effects of gypsy moth defoliation on acorn production (the seed source for oak regeneration), and the forest floor regeneration environment were investigated. Parameters measured included: acorn quantity, weight, development, and viability; litterfall; and forest floor depth and biomass. Nineteen plots in north-central Virginia and western Maryland on which trees suffered heavy, moderate, or no defoliation were monitored over a two-year period.

Master of Science

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Winters, Amanda. "Effects of Warming and Predation on Invertebrate Activity". Bowling Green State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1499357799174464.

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Tabatchnick, Melissa Danielle. "Mercury Speciation in Temperate Tree Foliage". Wright State University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=wright1284516685.

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Menezes, Luciano Carlos Sobral de. "Estrutura e produção de serapilheira de floresta de mangue na região estuarina-lagunar do baixo São Francisco sergipano". Universidade Federal de Sergipe, 2010. https://ri.ufs.br/handle/riufs/6546.

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The watershed of São Francisco River has suffered drastic degradation processes, with emphasis on the environmental damages created in the lower São Francisco. The river estuary has very extended mangrove areas threatened by human actions such as shrimp farming and the removal of timber to be used in construction. The characteristics of mangrove areas at the mouth of the river have not been enough studied mostly from changes occurred in the last two decades. The structural behavior of mangrove forests is a response to environmental conditions and greater structural development is related to subsidies of rainfall and tidal near the equatorial zones, under the influence of the intense convective activity of the intertropical convergence zone. This zone, in general, includes latitudes between 10 ° and 15 ° from the Equator. The structure of the forest is defined based on various parameters, such as species composition, diameter at breast height (1.30 m substrate), height, basal area, density, spatial distribution and distribution by class of diameter, and spatial patterns of species distribution. Significant amount of nutrients can return to the soil through the decomposition of leaves, stems, fruits, flowers and animal remains and fecal material, components that defines litterfall or litter, and is a parameter frequently used to evaluate the ecosystems productivity. The objective of this work was to evaluate the structural behavior of the mangrove litter production and estuarine river San Francisco.
A Bacia Hidrográfica do São Francisco vem sofrendo processos de degradação, merecendo destaque o passivo ambiental criado no seu baixo curso. Uma extensa área de manguezal da região estuarina do São Francisco destaca-se por apresentar áreas constantemente ameaçadas por ações antrópicas como a carcinicultura assim como a retirada de madeira para utilização na construção de habitações. A especificidade das características das áreas desse manguezal ainda não foi suficientemente estudada, principalmente a partir das alterações ocorridas no baixo curso do rio nas duas últimas décadas. O comportamento estrutural dos bosques de mangue é uma resposta às condições ambientais existentes, e estes ecossistemas atingem maior desenvolvimento estrutural onde são grandes os subsídios das chuvas e das marés próximas às zonas equatoriais, que estão sob influência da intensa atividade convectiva da zona intertropical de convergência. Essa zona, de forma geral, compreende latitudes com limite máximo entre 10° e 15° a partir do Equador. A estrutura do bosque é definida em função de diversos parâmetros, cabendo destaque para composição de espécies, o diâmetro à altura do peito (1,30 m do substrato), altura, área basal, densidade, distribuição espacial e distribuição por classe diamétrica, e padrões de distribuição espacial das espécies componentes da floresta. Significativa quantidade de nutrientes pode retornar ao solo por meio da decomposição das folhas, caules, frutos, flores, bem como restos de animais e material fecal, componentes que formam a serapilheira ou litter, sendo este um parâmetro freqüentemente usado para avaliação da produtividade de ecossistemas. O objetivo deste trabalho foi avaliar o comportamento estrutural do manguezal e a produção de serapilheira na região estuarina do rio São Francisco.

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Cabianchi, Giovana Mendonça. "Ciclagem de nutrientes via serapilheira em um fragmento ciliar do rio Urupá, Rondônia". Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/64/64135/tde-05102010-144343/.

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Os objetivos deste estudo foram: estimar a produção e a decomposição de serapilheira, quantificar os macronutrientes, além de avaliar a estrutura da vegetação e a composição florística de uma floresta de várzea em uma região sob forte influência antrópica no sudoeste da Amazônia. O conhecimento destes processos é extremamente importante, uma vez que tais informações fornecem dados essenciais para estimar a produção líquida destes sistemas, sua ciclagem de nutrientes, além de auxiliar na recuperação de áreas degradadas através de planos de manejo adequados. As coletas de serapilheira foram realizadas quinzenalmente, durante o período de Setembro de 2005 a Agosto de 2007 e o experimento de decomposição foi realizado no período de um ano. O levantamento florístico e as medidas de estrutura florestal foram realizadas em campanha intensiva em Agosto de 2009. A produção média anual de serapilheira foi de 12,7 t ha-1, com elevado grau de sazonalidade, apresentando maior produção durante os meses mais secos do ano. A produção para as frações obedeceu à seguinte ordem: folhas >> galhos > miscelânea. O retorno médio anual de carbono via serapilheira foi de 5,4 t ha-1. Em termos de proporção, existem quase duas vezes mais carbono sendo depositado no período seco do que no chuvoso. A devolução média anual de N foi de 199,6 kg ha- 1.O grande retorno deste elemento está relacionado à elevada deposição de serapilheira. A eficiência na utilização de nutrientes (EUN) foi de 57,9, valor considerado relativamente baixo, indicando que o suprimento de nitrogênio não é limitante nesta floresta. A razão C:N foi alta para as duas etapas do experimento de decomposição, atingindo valor máximo no início da estiagem (40,0), influenciando o processo de decomposição, que foi relativamente lento, principalmente durante os meses mais secos do ano. O valor médio anual do coeficiente k foi de 0,9 para os litterbags e 0,7 para o método da serapilheira acumulada. Durante o processo de decomposição predominou a imobilização de N e houve liberação lenta de C. O balanço parcial de carbono indica que cerca de 342,3 kg ha-1 de carbono são liberados anualmente para outros compartimentos do ecossistema, representando cerca de 34,2% da troca líquida do ecossistema. Para o inventário florestal foram medidos todos os indivíduos com DAP > 3,2 cm, totalizando 2.170 indivíduos. As árvores com DAP < 20,0 cm representaram 49,1% do total da floresta. Foi observado decréscimo progressivo na concentração de indivíduos conforme o aumento do diâmetro, indicando que a população está estável e provavelmente, crescendo. Para a composição florística foram identificados 266 indivíduos com DAP > 10 cm, sendo observadas 43 espécies, 17 famílias, e 4 espécies não identificadas. As principais famílias encontradas foram Leguminoseae (30,2%), Palmae (9,3%), Anonaceae (7,0%) e Sapotaceae (7,0%). O índice de diversidade de Shannon-Winer (H) foi 3,2. A área basal foi de 24,3 m2 ha-1. Estes valores são similares aos encontrados em florestas na região sul/sudoeste da Amazônia, situando-se abaixo dos valores na Amazônia Central. Os menores valores de área basal implicam em menor biomassa florestal, e consequentemente, em menores emissões de CO2 nesta região em caso de queimadas
The objectives of this study were to estimate litterfall production and decomposition, macronutrients and to evaluate the structure and floristic composition of a varzea Forest in a region under strong anthropogenic influence in southwest Amazonia. Knowledge about these processes is extremely important, since they provide information on ecosystem net production, nutrient cycling and can serve as basis for degraded áreas restoration based on adequate management strategies. Litter was sampled biweekly from September 2005 to August 2007, while decomposition was measured during one year. Floristic survey and forest structure measurements were done in August 2009. Average annual litter production was 12.7 t ha-1, with strong seasonality and higher production during drier months. In terms of different litter fractions production followed the order leaves>>branches>miscellaneous. Average annual C deposition via litterfall was 5.4 t ha-1. Proportionally, almost twice as much C returns to the forest ground in the drier season. Average annual N deposition was 199.6 kg ha-1, which is related to relatively high litterfall deposition. Nutrient use efficiency (NUE) was 57.9, a value that can be considered relatively low, indicating that nitrogen supply is not a limiting factor in this forest. C:N ratios were high in both seasons, with maximum (40) occuring at the beginning of dry season, which probably influenced and promoted low decomposition rates, specially during drier months. Average annual k was 0.9 for litterbags and 0.7 based on litter accumulation. During decomposition N imobilization and slow C release predominated. Partial carbon budget indicates that around 342.3 kg C ha-1 are cycled via litterfall, representing 34.2% of net ecosystem exchange. For the forest inventory all individuals with diameter at the breast height (DBH) >3.2 cm were measured, totalling 2.170 individuals. Trees with DBH < 20.0 cm represent 49.1% of the forest. A progressive decrease in individuals as diameter size increase indicated that this forest is stable or even growing. The floristic composition was based on 266 individuals with DBH > 10 cm, composed of 43 species, 17 families and 4 unidentified species. Major families were Leguminoseae (30.2%), Palmae (9.3%), Anonaceae (7.0%) e Sapotaceae (7.0%). Shannon-Winer index (H) was 3.2. Basal area was 24.3 m2 ha-1. These values are similar to other findings in the south and southwest of the Amazon and lower than those of the central Amazon. Smaller basal area indicates smaller forest biomass and consequently smaller CO2 emission in case of fires in this region

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XUE, Li, 立. 薛, Yoshiya TADAKI i 良也只木. "スギのリターフォールおよび養分の季節変化と養分利用効率". 名古屋大学農学部付属演習林, 1996. http://hdl.handle.net/2237/8717.

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Bizuti, Denise Teresinha Gonçalves. "Ciclagem do fósforo em floresta ombrófila densa dos núcleos de Picinguaba e Santa Virgínia - SP". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/91/91131/tde-30062011-154523/.

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Atualmente observa-se a necessidade de projetos direcionados à interação solo-planta em ecossistemas naturais, envolvendo a recuperação de áreas degradadas. Vários estudos têm demonstrado que a ciclagem de nutrientes, principalmente em solos de baixa fertilidade, é a responsável pela manutenção das florestas. Em especial, a ciclagem do fósforo requer maiores atenções pelo fato da baixa disponibilidade e da elevada capacidade de adsorção desse elemento em solos tropicais. Dessa forma, o fósforo orgânico assume considerável importância por reduzir os efeitos de adsorção, permanecendo na forma de compostos orgânicos no solo. O objetivo desse trabalho foi avaliar a ciclagem do fósforo ao longo da topossequência na Floresta Ombrófila Densa, na Restinga e na pastagem dos Núcleos de Picinguaba (Ubatuba-SP) e Santa Virgínia (São Luis do Paraitinga-SP), determinando quantitativamente os compartimentos inorgânicos e orgânicos nos quais o fósforo está retido. Na Floresta Ombrófila Densa foram avaliadas as áreas de Mata de Restinga (5 a 20m de altitude), de Floresta Ombrófila Densa de Terras Baixas (50 a 100m), de Floresta Ombrófila Densa Submontana (300 a 600m de altitude), de Floresta Ombrófila Densa Montana (ao redor de 1000m de altitude) e também uma área de pastagem (810m). Foram coletadas amostras de serapilheira de acordo com a variação sazonal (estações seca e úmida). Os estudos da fertilidade do solo foram realizados até 0,4m de profundidade (0-5, 5-10, 10-20, 20-30 e 30-40 cm no perfil do solo), para cada um das áreas estudadas. O fracionamento sequencial e estoques de fósforo foram realizados para cada camada. No solo e na serapilheira foram quantificados os teores e estoques de N e C para correlacioná-los com o P. As maiores produções de serapilheira foram verificadas nas fitofisionomias de menores altitudes. Quanto aos teores e estoques de C, N e P na serapilheira apenas os teores de N diferiram entre as áreas. Com relação às áreas estudadas, a Restinga apresentou maior eficiência na ciclagem de P, como também tendência a uma menor resiliência em relação às demais fitofisionomias. As áreas avaliadas apresentaram a mesma capacidade de fornecimento do compartimento de Po moderadamente lábil (Po NaOH), independente da altitude, da presença dos agentes fixadores e da idade geológica do solo. Através do fracionamento sequencial do P, verificou-se que a contribuição dos fósforos orgânicos (Po NaHCO3 e Po NaOH) presentes no solo, em função dos compartimentos lábeis e moderadamente lábeis disponíveis à planta a curto e médio prazo, em geral, atingiu 50% para as camadas superficiais do solo.
Currently projects regarding soil-plant interaction in natural ecosystems that involve recovery of degraded areas are in high demand. Studies have shown that nutrient cycling, especially in low fertility soil, is responsible for forest maintenance. Phosphorus cycling demands higher attention because of its low availability and high adsorption capacity in tropical soil. Therefore, organic phosphorus is important for reducing the effect of such processes, maintaining itself in the form of organic compounds in soil. The aim of this study was to evaluate phosphorus cycling throughout altitudinal gradient of Rain Forest in the Picinguaba (Ubatuba-SP) and Santa Virginia (São Luis do Paraitinga) Study Centers, quantitatively determining organic and inorganic compartments in which phosphorus is retained. In the Rain Forest, areas of Restinga Forest (altitude of 5 to 20m), Lowland Forest (50 to 100m), Submontane Forest (300 to 600m), Montane Forest (aroud 1000m altitude) and also pasture areas (810m) were evaluated. Litterfall samples were collected according to seasonal variation (dry and wet seasons). Soil fertility studies were carried out up to 0.4m of depth, in layers of 0-5, 5-10, 10-20, 20-30 e 30-40 cm, a total of five layers of soil for each ecosystem studied. For each layer, sequential fractionation of phosphorus was carried out. In soil and litterfall, chemical analysis of N and C contents to evaluate the relation of such compounds with P were also carried out. The highest productions of litterfall were found in lower altitude phytophisionomies. As for levels and storage of C, N and P of litterfall, only the levels of N differed among the areas. Related with the studied areas, Restinga presented higher efficiency in P cycling, as well as lower resilience regarding other phytophisionomies. The evaluated areas presented the same supplying capacity as the moderate labile Po compartment (Po NaOH), independent of altitude, fixating agents and of geological age of soil. Because of sequential fractionation of phosphorus, the contribution of organic phosphorous (Po NaHCO3 and Po NaOH), present in the soil, achieved in general 50% of topsoil layers, because of labile and moderate labile compartments available to plants in a short and medium term.

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Chaves, Filipe de Oliveira. "Caracterização e relações ambientais da produção de serapilheira em florestas de mangue da baía de Guanabara, Rio de Janeiro - Brasil". Universidade de São Paulo, 2007. http://www.teses.usp.br/teses/disponiveis/21/21131/tde-19072007-133914/.

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Este trabalho objetivou a quantificação da serapilheira produzida nas florestas de mangue e a análise da sua relação com fatores ambientais na baía de Guanabara. A produção total média bianual variou entre 4,7 e 22,8 t.ha-1.ano-1, com média de 13,4 (± 3,79) t.ha-1.ano-1 em vinte quatro estações distribuídas no estuário. Na baía a salinidade da água intersticial nas estações demonstrou uma relação inversamente proporcional com a produção. A produção da folha abrangeu, em média, 60% da queda total de serapilheira, seguido por propágulos (18,7%) e galhos (13%). As variações temporais foram sazonais, com diferença estatistica significativa entre os meses de maior (verão) e menor (inverno) produção. Os anos de amostragem também apresentaram grandes diferenças na produção de serapilheira, ligada a queda de propágulos, particularmente de Rhizophora mangle, responsáveis em muitos casos pelos picos encontrados. As variáveis estruturais definiram importantes relações nas transversais, com regressão negativa entre a densidade e uma positiva para o DAP médio e a produção de serapilheira. Obteve-se uma correlação positiva entre a variação da produção e a temperatura média do ar, mas com coeficientes baixos. Ao final do estudo foi possível atestar a elevada importância dos manguezais como produtores de detritos na baía realçando seu importante papel dentro do estuário.
This work objectified the quantification of litterfall produced in mangrove forests and the analysis of its relation with environmental factors in Guanabara bay. The biannual average total production varied between 4,7 and 22,8 t.ha-1.year-1, with an average of 13,4 (± 3,79) t.ha-1.year-1 in twenty four stations distributed in the estuary. In this bay, the salinity of interstitial water demonstrated an inversely proportional relation with production. Leaf production comprised, on average, 60% of total litter fall followed by propagule (18,7%) and wood (13%). The temporal variation was seasonal with a maximum in the summer season and minimum in the winter season. The two years of sampling also showed great differences in litterfall production that were linked to the fall of propagules, particularly of Rhizophora mangle, responsible in many cases for the formation of peaks. Structural variables defined important relations for the transects, with negative regression between density and positive for DBH and litterfall production. Litter production was highly variable and negatively correlated with air temperature. In the end of this study, it was possible to attest the importance of mangrove forests as producers of litter in the bay, enhancing its important role for the estuary.

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Toscan, Maria Angélica Gonçalves. "Produção de serapilheira e chuva de sementes no corredor de biodiversidade Santa Maria, PR". Universidade Estadual do Oeste do Parana, 2013. http://tede.unioeste.br:8080/tede/handle/tede/730.

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Made available in DSpace on 2017-07-10T14:38:36Z (GMT). No. of bitstreams: 1 Maria Angelica.pdf: 2408502 bytes, checksum: e0db92a0df4c5e411e73b051a6b0cc76 (MD5) Previous issue date: 2013-02-28
This study aimed to characterize litter production and seed rain of RPPN Fazenda Santa Maria, considered a forest fragment late (FT), and to compare these indicators of ecological succession in a initial fragment (FI) and a fragment reforested (FRt). For this, were sampled nine plots of 20 x 20 m in RPPN Fazenda Santa Maria, and three of these plots were selected for the comparison of indicators of ecological succession with the other two fragments, which were also sampled three permanent plots in each. In these plots were distributed four traps of 0,5 x 0,5 m, the material deposited was collected monthly from jun/2011 to May/2012 and separated in the fractions of leaves, branches, reproductive materials and miscellaneous. From the reproductive materials the seed rain was analyzed. Among the results obtained in the characterization of RPPN Fazenda Santa Maria (FT) are the annual litterfall production of 11.886 kg.ha-1, being August and September the months of higher productions. In seed rain were collected 18,300 seeds distributed in 79 morphospecies. The months with the highest abundance of seeds were September (19%), October (20%), November (27%) and March (15%). The life form predominant was tree with 76,27% of the species, followed by climbers with 20,34% and herbaceous with 3,39%. Among the tree species, 39,02 % were represented by successional category of pioneer, while the early and late secondary categories accounted for 21,95% each and the climax 17,07%. The zoochory predominated among dispersal syndromes with 52,54%, while anemochory occurred in 38,98% and autocory in 8,47%. Already the results obtained in the comparative study of litterfall production and seed rain between the different fragments were: FT with the highest annual production (11.560 kg.ha-1), followed by FRt (9.330 kg.ha-1) and FI (7.838 kg.ha-1), but these values were not significantly different by ANOVA. In FRt were collected 7.167 seeds of 33 species and in FI 4.751 seeds of 38 species, both with predominance of seeds of pioneer and anemochoric species. In FT (RPPN Fazenda Santa Maria) were collected 2.173 seeds of 49 species, with a predominance of seeds of late secondary and climax and zoochoric species, where it was also possible to observe the asynchronism in the production of fruits by species of trees and climbers. Despite the reduction in the number of replicas which led to a reduction in the number of seeds and species, the FT fragment showed the best results among the other two. Through the characterization of litter production and seed rain, the RPPN Fazenda Santa Maria can be considered an area of forest late, with high potential for regeneration and high availability of fruit to the fauna. And with the comparative study between the two indicators, it can be observed that considering the studied areas and the number of replicas in each fragment, the seed rain was a better indicator of ecological succession in relation to litterfall production
Este trabalho teve como objetivo caracterizar a produção de serapilheira e a chuva de sementes da RPPN Fazenda Santa Maria, considerada um fragmento de floresta tardia (FT), bem como comparar estes indicadores de sucessão ecológica em um fragmento inicial (FI) e um fragmento reflorestado tardio (FRf). Para isso, foram amostradas nove parcelas de 20 x 20 m na RPPN Fazenda Santa Maria, sendo que três dessas parcelas foram selecionadas para a comparação dos indicadores de sucessão ecológica com os outros dois fragmentos, onde também foram amostradas três parcelas permanentes em cada. Nessas parcelas foram distribuídos quatro coletores de 0,5 x 0,5 m, o material depositado foi coletado mensalmente de jun/2011 a mai/2012 e triado nas frações de folhas, ramos, materiais reprodutivos e miscelânea. A partir dos materiais reprodutivos a chuva de sementes foi analisada. Entre os resultados obtidos na caracterização da RPPN Fazenda Santa Maria (FT) estão produção anual de serapilheira de 11.886 kg.ha-1, sendo agosto e setembro os meses de maiores produções. Na chuva de sementes foram coletadas 18.300 sementes, distribuídas em 79 morfoespécies. Os meses com maior abundância de sementes foram setembro (19%), outubro (20%), novembro (27%) e março (15%). A forma de vida predominante foi arbórea com 76,27% das espécies, seguido de lianas com 20,34 % e herbáceas com 3,39%. Entre as espécies arbóreas, 39,02% pertenciam à categoria sucessional de pioneiras, enquanto as categorias secundárias iniciais e tardias representaram 21,95% cada e as climácicas 17,07%. A zoocoria predominou entre as síndromes de dispersão com 52,54%, a anemocoria ocorreu em 38,98% e a autocoria em 8,47%. Já os resultados obtidos no estudo comparativo da produção de serapilheira e chuva de sementes entre os diferentes fragmentos foram: FT com a maior produção anual (11.560 Kg.ha-1), seguida de FRt (9.330 Kg.ha-1) e FI (7.838 Kg.ha-1), porém esses valores não apresentaram diferença significativa pela ANOVA. Em FRt coletaram-se 7.167 sementes de 33 espécies e em FI 4.751 sementes de 38 espécies, ambos com predomínio de sementes de espécies pioneiras e anemocóricas. Em FT (RPPN Fazenda Santa Maria) coletaram-se 2.173 sementes de 49 espécies, com predomínio de sementes de espécies secundárias tardias e climácicas e zoocóricas, onde também foi possível observar o assincronismo na produção de frutos por espécies arbóreas e lianas. Apesar da redução no número de réplicas o que levou a redução no número de sementes e espécies, o fragmento FT apresentou os melhores resultados entre os outros dois. Por meio da caracterização da produção de serapilheira e da chuva de sementes, a RPPN Fazenda Santa Maria pode ser considerada uma área de floresta tardia, com elevado potencial de regeneração e elevada disponibilidade de frutos para a fauna. E com o estudo comparativo entre os dois indicadores, pode-se observar que considerando as áreas estudadas e o número de réplicas em cada fragmento, a chuva de sementes foi um melhor indicador de sucessão ecológica em relação à produção de serapilheira

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Mello, Ricardo Silva Pereira. "Detecção de padrões de coexistência arbórea e processos ecológicos em zona de contato de florestas ombrófilas montanas no sul do Brasil". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2006. http://hdl.handle.net/10183/10941.

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A tese versa sobre a detecção e avaliação de padrões de coexistência de espécies arbóreas, buscando esclarecer as relações entre a diversidade fito-estrutural e os fatores condicionantes em escalas local e regional em uma zona de contato entre duas regiões fitoecológicas (Florestas Ombrófilas Mista e Densa). O trabalho está dividido em duas abordagens; a primeira trata de um inventário fitossociológico de comunidades definidas como “sítios”, onde o grau de singularidade local é avaliado através da identidade das espécies com maior valor de importância (VI) estrutural e de suas possíveis conexões fitogeográficas, bem como através de indicadores de diversidade alfa e beta. Na segunda abordagem, comunidades são definidas estatisticamente (Multivariada, Análise do Valor Indicador das Espécies) com base na composição e abundância de espécies (área basal dos troncos), testando-se a hipótese de que comunidades distintas devem diferir pelo menos na diversidade específica, fertilidade do solo e ou produtividade primária (produção de serrapilheira PS). O estudo foi realizado no Centro de Pesquisas e Conservação da Natureza Pró-Mata, localizado na borda sudeste do Planalto Meridional Brasileiro (29o30’S; 50o11’W). Cinco sítios de 100m x 100m (dois sítios no planalto, dois na encosta e um na borda planalto-encosta) foram selecionados, onde em cada sítio as árvores (DAP>10 cm) foram medidas e determinadas em vinte e uma unidades amostrais de 100m2 (regularmente distribuídas). Sessenta e seis espécies foram levantadas, no conjunto Cabralea canjerana e Myrcia retorta tiveram os maiores valores de importância. A primeira caracteriza a encosta e a segunda o planalto, sendo ambas co-dominantes no sítio da borda do planalto-encosta. Riqueza e diversidade foram maiores nessa borda, menor no planalto e intermediária na encosta. A beta-diversidade apresenta-se maior com medidas de abundância do que apenas com a composição de espécie, em função da diferenciação das dominantes, caracterizando comunidades discretas, indicando ao mesmo tempo um contínuo gradiente florístico. As análises de ordenação e agrupamento foram utilizadas com dois tamanhos de unidade amostral (100 m2 e 500 m2), das quais somente a última apresentou padrões interpretáveis, similares aos obtidos fitossociologicamente nos sítios, onde dois principais tipos de vegetação apresentam afinidades fitogeográficas e riqueza de espécies peculiares. Os subgrupos refletiram processos histórico-ecológicos mais recentes, como a perturbação antrópica e condições locais especiais. A determinação de espécies com valores indicadores significativos é útil para a diferenciação ecológica dos tipos de comunidades. Apenas uma comunidade diferiu significativamente das demais na fertilidade do solo, devido à condição especial topográfica e litológica. A produção de serrapilheira destas florestas foi similar aos valores médios das florestas brasileiras tropicais e subtropicais. Conclui-se que, na zona de transição estudada, tende a ter um ecótono da vegetação associado à transição geomorfológica planalto-encosta. Algumas considerações sobre o alcance metodológico de detecção de biodiversidade e das perspectivas de pesquisas integradas sobre os processos ecossistêmicos são apresentadas.
This thesis searches to detect patterns of the arboreal species coexistence on a transition zone of two phyto-ecological regions, Mixed and Dense Rainforests, contributing to the knowledge of ecological processes on the local to regional scale. The work is divided in two approaches; the first is a phytosociological inventories aiming to answer if in this zone exists a set of local communities with similar floristic-structural patterns, or not, and what are their phytogeographical affinities; the second tests the hypothesis that the communities types statistically defined have indicator species and differs in specific diversity attributes, soil fertility and the primary productivity (litterfall). The study was carried out at CPCN Pró-Mata, a research center located on the southeastern border of the Meridional Brazilian Plateau (29o30’S; 50o11’W). Five sites of 100 x 100m (two plateau sites, two slope sites, and one plateau-slope site) were selected; the trees (DBH>10cm) were measured and determined and twenty-one sampling units of 100m2 (regularly distributed), in each site. Sixty-six species were surveyed. Cabralea canjerana and Myrcia retorta had the highest importance value indexes. The first species characterizes the slope; the second species characterizes the plateau; and both are co-dominant at the slope-plateau site. Richness and diversity (Shannon index) were higher at slope-plateau transition, lower at the plateau and intermediate at the slopes. The Beta diversity shows that the sharpness between slope and plateau communities is more associated to species abundance than to species composition only. The Ordination and Cluster analyses were used with two sized sampling units (100 m2 and 500m2), which only the latter showed interpretable patterns, similar to those phytosociological results, where emerges the two main vegetation types indicated the broader regional floristic affinities and its influence on species richness. The sub-groups reflected more recent local historical-ecological processes, mainly identified as anthropic disturbance regime and special local conditions. The Indicator Species Analysis was very responsive to the present objective helping to define the best indicative species and ecological context. Soils differ significantly only for one group, differentiated by special topographic condition and lithologic origin. The annual litterfall of these forests were equivalent among sites and they are similar to register for average the tropical and subtropical Brazilian forests. Conclude that in this transition zone trends to have a vegetation ecotone is associated to the geomorphologic transition slope-plateau. Then, communities types statistically defined reflect hierarchically phytoecological regional affinities and particular ecological conditions. Some considerations about methodological biodiversity detection integrated to researches about ecosystem process are shown.

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Silva, Julio Cesar Medeiros da. "Ciclagem biogeoquímica de nutrientes em Eucalyptus dunnii Maiden em uma microbacia hidrográfica experimental do bioma Pampa". Universidade Federal de Santa Maria, 2014. http://repositorio.ufsm.br/handle/1/3776.

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The planting of large areas with exotic species is a consequence of the evolution of an entire industrial structure; it aims to meet the demand for forest products. The use of these species requires knowledge on the techniques of soil preparation, fertilization, weed competition, and residue management and harvest intensity, among others. The objective of this study was to evaluate aspects of biogeochemical cycling of nutrients in Eucalyptus dunnii established in a watershed located in the Pampa biome, municipality of Alegrete/RS in area belonging to Stora Enso S.A. The following parameters were evaluated monthly: the rainfall, within and outside the forest stand, litterfall deposition, the total biomass and the output of nutrients by runoff from the watershed. Precipitation was sampling through twelve collectors of internal precipitation, twelve collectors solution resulting from stemflow and three external collectors. The runoff was sampling with aid of container for water collection of 500 ml, made in the spillway of a flume. Sampling of litterfall was obtained through sixteen collectors of 0.5 m² of floor area, to evaluate the fractions of leaves and miscellany, in addition, sixteen areas of collecting thick branches. The determination of biomass occurred after the cutting of twelve trees, considered representative of four diameter classes, with the excavation of their respective roots. The rainfall within the forest stand, litterfall deposition and biomass were evaluating in four installments. The rainfall, biomass production and litterfall and the output of ecosystem nutrients by runoff were evaluating for quantity, the concentration of elements and the contribution thereof. It was founded that the total rainfall was 1385.28 mm yr-1 corresponding to the average of 2012 and 2013 value and the internal precipitation was 91.4% and the stemflow was 1.3%, where 7.61% were intercepting by the canopy. The annual effective precipitation was 1242.69 mm, corresponding to approximately 90% of the local rainfall. It has been found that the interaction of rain with the results in the leaching of surface of the tissue, increasing in 421% the concentration of K, 24.0% the concentration of Ca and 185% the concentration of Mg. In the internal precipitation, the order of predominance was Cl > K+ > SO4- > Ca²+ > Mg²+ and the stemflow, in the order of predominance was K+ > Cl > Mg²+ > Ca²+ > SO4- . The total biomass of the stand was 67.49 Mg ha-1, with a decreasing sequence of accumulation of biomass: wood stem > root > trunk bark > branches > leaves. The total quantity of nutrients in kg ha-1, was: 211.51 of N; 22.12 of P; 199,88 of K; 39,70 of Ca; 86.42 of Mg and 25.05 of S; and the micronutrients in g ha-1, was 562.57 of B; 401.46 of Cu; 9913.28 of Fe; 31877.82 of Mn and 766.96 of Zn. There was accumulation of Mn in biomass components, in addition that the highest concentrations of nutrients are in the tissues of the canopy. The average litterfall production was 7.0 Mg ha-1 yr-1. The forming material of the litterfall consists of sheets, contributing the majority of the deposition (64.3%) followed by twigs (17.5%), thick branches (10.2%) and miscellaneous (7.9%), being Ca the most representative element into leaves, twigs and boughs, presenting only in the miscellaneous fraction, less than N. The P and S elements reported the lowest concentrations. The total transfer of macronutrients was 163.0 kg ha-1 and micronutrients was 9.7 kg ha-1, the macronutrient levels found in litterfall followed the descending order Ca > N > K > Mg > S > P and micronutrient followed the descending order of Mn > Fe > B > Zn > Cu. Three harvesting systems were simulated, completely tree above the ground; wooden trunk + bark and stem wood only. In all simulations, the balances were positive. The total retention of crop residues on the forest site can provide a higher percentage of return of nutrients to the soil. The weight of the harvest Eucalyptus dunnii Maiden, planted in sandy soil and low fertility affected, albeit positively, differently biogeochemical cycling of nutrients
O plantio de grandes áreas com espécies exóticas é uma consequência da evolução de toda uma estrutura industrial, que tem como objetivo atender a demanda por produtos florestais. O uso destas espécies exige conhecimentos quanto às técnicas de preparo de solo, adubação, mato-competição, além de manejo de resíduos e intensidade de colheita, dentre outras. O objetivo deste trabalho foi avaliar aspectos da ciclagem biogeoquímica de nutrientes em um povoamento de Eucalyptus dunnii, estabelecido em uma microbacia hidrográfica localizada no bioma Pampa, município de Alegrete/RS, em área pertencente à empresa Stora Enso S.A. Os seguintes parâmetros foram avaliados mensalmente: a precipitação pluviométrica, dentro e fora do povoamento, a deposição de serapilheira, biomassa total, além da saída de nutrientes por deflúvio da microbacia hidrográfica. A precipitação foi amostrada por meio de doze coletores de precipitação interna, doze coletores de solução decorrente do escorrimento pelo tronco e por três coletores externos ao plantio florestal. O deflúvio foi amostrado com auxílio de recipientes de 500 ml para coleta de água, realizada no vertedouro com uma calha tipo flume. A amostragem da serapilheira foi obtida por meio de dezesseis coletores de 0,5 m² de área útil, para avaliação das frações folhas e miscelânea, além de dezesseis parcelas de coleta de galhos grossos. A determinação de biomassa ocorreu a partir da derrubada de doze árvores, consideradas representativas de quatro classes de diâmetro, junto da escavação das respectivas raízes. A precipitação dentro do povoamento, a deposição de serapilheira e a biomassa foram avaliadas em quatro parcelas. A precipitação, a produção de biomassa e de serapilheira e a saída de nutrientes do ecossistema por deflúvio, foram avaliadas quanto à quantidade, a concentração de elementos e ao aporte dos mesmos. Constatou-se que a precipitação total foi de 1.385,28 mm ano-1, valor correspondente à média de 2012 e 2013, já a precipitação interna foi 91,4% e o escorrimento pelo tronco foi 1,3%, sendo que 7,61% foram interceptados pelo dossel. A precipitação efetiva anual foi 1.242,69 mm, correspondendo a aproximadamente 90% da precipitação pluviométrica local. Verificou-se que a interação da chuva com as copas possibilitou a lixiviação de metabólitos presentes na poeira atmosférica depositada na superfície dos tecidos, aumentando em 421% a concentração de K, em 24,0% à concentração de Ca e em 185% a concentração de Mg. Na precipitação interna, a ordem de predominância foi Cl- > K+ > SO4- > Ca²+ > Mg²+ e para o escorrimento pelo tronco a ordem de predominância foi K+ > Cl- > Mg²+ > Ca²+ > SO4-. A biomassa total do povoamento foi de foi de 67,49 Mg ha-1, com sequência decrescente de acúmulo de biomassa: madeira do tronco > raiz > casca do tronco > galhos > folhas. A quantidade total de macronutrientes, em kg ha-1, foi de: 211,51 de N; 22,12 de P; 199,88 de K; 39,70 de Ca; 86,42 de Mg e 25,05 de S; e a de micronutrientes, em g ha-1, foi de 562,57 de B; 401,46 de Cu; 9.913,28 de Fe; 31.877,82 de Mn e 766,96 de Zn. Houve acúmulo de Mn nos componentes da biomassa, além de que as maiores concentrações de nutrientes estão nos tecidos das copas. No entanto, a maior quantidade de biomassa encontra-se na madeira. A produção de serapilheira média foi de 7,0 Mg ha-1 ano-1. O material formador da serapilheira é constituído por folhas, contribuindo com a maior parte da deposição (64,3%) seguida por galhos finos (17,5%), ramos grossos (10,2%) e miscelânea (7,9%), sendo Ca o elemento mais representativo nas frações folhas, galhos finos e galhos grossos, apresentando-se apenas na fração miscelânea, inferior ao N. Os elementos P e S apresentaram as menores concentrações. A transferência total de macronutrientes foi de 163,00 kg ha-1 e de micronutrientes foi 9,73 kg ha-1, teores de macronutrientes encontrados na serapilheira apresentaram a seguinte ordem Ca > N > K > Mg > S > P e os teores de micronutrientes seguiram a ordem decrescente de Mn > Fe > B > Zn > Cu. Foram simulados três sistemas de colheita: árvore inteira; madeira do tronco+casca e somente madeira do tronco. Em todas as simulações os saldos foram positivos. A permanência total dos resíduos da colheita no sítio propiciou um maior percentual de retorno de macronutrientes ao solo. O peso da colheita do Eucalyptus dunnii Maiden, plantado em solo arenoso e de baixa fertilidade natural afetou, ainda que positivamente, de forma diferenciada a ciclagem biogeoquímica dos nutrientes.

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Braga, Antonio Jorge Tourinho. "Estudos ecológicos em floresta estacional semidecidual, Viçosa - MG". Universidade Federal de Viçosa, 2010. http://locus.ufv.br/handle/123456789/535.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
The present work was aims to realize ecologic studies in Seasonal Semideciduous Forest (initial and advanced forests) for manner to valuation the floristic composition and phytossociology, of correlations between soil factors and floristic variation, the litterfall, the seed rain and seed bank. The study was realized in Mata da Agronomia in Viçosa, MG (20°46 S e 42°52 W), individual trees with ≥ 15 cm circumference at breast height (DCH) were sampled in 20 - 25 x 10 m plots (10 plots in each site). On the sampled center was an installed quadrate litter trap with 1x1 m, where was monthly collect the material deposited between April/2007 and March/2008. Forty soil samples total in two distinct period (drought station finish and rainy station finish and arranged for germinate in wooden boxes (0,5 x 0,5 x 0,1 m) in shading of 60%. The soil samples were collected at 0-10 cm depth and submitted to chemical and physics analysis. The floristic lifting registered one total the 820 individuals were registered, once, 440 in the initial forest and 380 in the advanced forest. The families show up in richest in initial forest were Fabaceae (137), Urticaceae (45) and Sapindaceae (41) and advanced forest were Fabaceae (103), Meliaceae (49) e Flacourtiaceae (34). In the continuum the Shannon diversity index (H ) was 3.82 nat.ind.-1 and the Pielou evenness (J ) was 0.84. The initial and advanced forests revealed the low similarity among theses forests by Sorensen index. While, the canonical correspondence analysis (CCA) indicated significant correlation between the trees species availed and the fertility chemical soil. The litter production annual in the initial forest (8,349.5 kg/ha) was superior signification of advanced forest production (6,712.8 kg/ha). On the seed rain study were recognized 84 taxa, where 41 species were identified distributed among 40 families in the initial forest and 24 species belonging to 13 families in advanced forest. The life form dominate was arborous and the dispersion syndrome was zoocory. Hundred nine taxa were sampled in the seed bank the forest altogether, 101 species were identified as belonging to 73 genera distributed among 40 families, 56 species commonness in two successional stages of forest and 49 species commonness of two levy period. The herbaceous individuals predomination in all forests and valuation epoch, whit not representation the fragility of the seed bank, by little quantity inhibitor herbaceous individuals in relation to overmuch herbaceous, arboreus and arbutus individuals wat contribute for successional dynamics.
O presente trabalho teve como objetivo realizar estudos ecológicos em Floresta Estacional Semidecidual (floresta inicial e avançada) por meio da avaliação da composição florística e fitossociológica, das correlações entre os fatores edáficos e vegetacionais, da produção de serapilheira, da chuva de sementes e do banco de sementes. O estudo foi realizado na Mata da Agronomia situada em Viçosa, MG (20°46 S e 42°52 W), onde foram alocadas 10 parcelas de 25 x 10 m em cada trecho, sendo amostrados todos os indivíduos com circunferência do tronco a 130 cm do solo (CAP) ≥ 15 cm. No centro de cada parcela foi colocado um coletor de 1x1 m, no qual foi realizadas coletas mensais do material precipitado entre abril de 2007 e março de 2008. Também foram coletadas 40 amostras do banco de sementes em dois períodos distintos (final da estação seca e chuvosa) e colocadas para germinar em caixas de madeira de 0,5 x 0,5 x 0,1 m sob 60% de sombreamento. Além dessas amostras, outras foram realizadas nas parcelas (camada de 0-10 cm) e submetidas à análise química e física. No levantamento florístico registrou-se o total de 820 indivíduos, sendo, 440 registrados na floresta inicial e 380 na floresta avançada. As famílias de maior riqueza específica na floresta inicial foram Fabaceae (137), Urticaceae (45) e Sapindaceae (41) e na avançada Fabaceae (103), Meliaceae (49) e Flacourtiaceae (34). Para o conjunto, o índice de Shannon (H ) e a equabilidade (J ) foram de 3,82 nat.ind.-1 e 0,84, respectivamente. As florestas inicial e avançada apresentaram baixo índice de similaridade florística. A análise de correspondência canônica (CCA) indicou correlação significativa entre a distribuição das espécies arbóreas avaliadas no perfil topográfico e a fertilidade do solo. A produção anual de serapilheira na floresta inicial (8349,5 kg/ha) foi significativamente superior à produção da floresta avançada (6712,8 kg/ha). No estudo de chuva de sementes foram reconhecidos 84 taxa, sendo 41 espécies pertencentes a 25 famílias na floresta inicial e 24 espécies pertencentes a 13 famílias na floresta avançada. A forma de vida dominante foi arbórea e a síndrome de dispersão predominante foi a zoocórica. No estudo do banco de sementes foram registrados 109 taxa no banco de sementes da floresta como um todo, sendo reconhecidas 101 espécies distribuídas em 73 gêneros de 40 famílias. Ocorreram 56 espécies comuns aos dois trechos de floresta e 49 espécies comuns aos dois períodos de coleta. Os indivíduos herbáceos predominaram em todas as florestas e épocas de avaliação, o que não representou a fragilidade do banco de sementes, pela pequena quantidade de invíduos herbáceos inibidores em relação aos demais herbáceos, arbóreos e arbustivos que contribuem para a dinâmica sucessional.

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Corrêa, Robson Schaff. "Ciclagem de nutrientes em Eucalyptus dunnii estabelecido no bioma Pampa". Universidade Federal de Santa Maria, 2011. http://repositorio.ufsm.br/handle/1/3739.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The goal of this study was to evaluate aspects of nutrients cycling in Eucalyptus dunnii by monitoring a stand throughout a year. This took place in Alegrete town, Rio Grande do Sul state, South Brazil, in an area of Stora Enso S/A, starting when stand was 16.5 months old. It was evaluated monthly rainfall and litterfall. Rainwater inside the stand was collected in 12 throughfall collectors and 12 stemflow collectors. The bulk precipitation was evaluated by two rainwater collectors located outside the stand. Assessing the litterfall, 16 collectors with 0.5 m² area were installed for the evaluation of leaves and miscellaneous (bark, reproductive material and branches - diameter less than or equal to 5 mm) fractions, plus the installation of 16 areas to collect thick branches (diameter greater than 5 mm). Rainwater and litterfall collectors were disposed in 4 blocks. Precipitation and litterfall were assessed for quantity, concentration of nutrients and input of these nutrients. Rainfall was 1586 mm y-1, with 7% interception by the stand. Throughfall accounted for 98% of effective precipitation, and the remaining 2% was stemflow. The concentration of ions in bulk precipitation was low, consistent with the rural areas of non-industrialized regions. Higher inputs occurred after the interaction of bulk precipitation with the forest canopy. It was fell 4.1 Mg ha-1 y-1 litterfall, where leaves corresponded to 93%, 6% of miscellaneous and 1% of thick branches. The higher concentration of macro and micronutrients was in general found in leaves fraction. The nutrient input was higher to litterfall, except for the macronutrient S.
O objetivo deste trabalho foi avaliar aspectos da ciclagem de nutrientes em Eucalyptus dunnii através do monitoramento de um povoamento durante o período de um ano, começando quando as árvores estavam com 16,5 meses de idade, no município de Alegrete, Rio Grande do Sul, em área pertencente à empresa Stora Enso S/A,. Foi avaliada, mensalmente, a deposição atmosférica dentro e fora do plantio, através de coletores de água da precipitação, e a deposição de serapilheira. A precipitação dentro do povoamento foi feita através de 12 coletores de precipitação interna e 12 coletores de solução decorrente do escorrimento pelo tronco. Já a precipitação global foi avaliada por dois coletores de precipitação instalados fora do povoamento e sem interferência do dossel. Para a amostragem da deposição de serapilheira foram instalados 16 coletores de 0,5 m² de área útil para avaliação das frações folhas e miscelânea (casca, material reprodutivo e galhos finos diâmetro menor ou igual a 5 mm), além da instalação de 16 áreas de coleta de galhos grossos (diâmetro maior que 5 mm). Tanto os coletores de precipitação dentro do plantio, quanto a deposição de serapilheira foram avaliadas em quatro parcelas. Precipitação e serapilheira foram avaliadas quanto à quantidade, à concentração de elementos e ao aporte dos mesmos. A precipitação global foi de 1586 mm ano-1, com 7% de interceptação pelo povoamento. A precipitação interna correspondeu a 98% da precipitação efetiva, sendo os 2% restantes relativos ao escorrimento pelo tronco. A concentração de íons, na precipitação global, foi baixa, condizente com áreas rurais de regiões não industrializadas. Ocorreu maior aporte de elementos após a interação da precipitação global com o dossel florestal. Foram depositados 4,1 Mg ha-1 ano-1 de serapilheira, sendo 93% de folhas, 6% de miscelânea e 1% de galhos grossos. A concentração de macro e micronutrientes foi, para a maioria dos elementos, encontrada na fração folhas. A devolução de nutrientes foi maior via deposição de serapilheira, com exceção para o macronutriente S.

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Machado, Deivid Lopes [UNESP]. "Aporte de serapilheira, fauna edáfica e matéria orgânica do solo em diferentes sistemas de restauração florestal". Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/141475.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
A composição e as características funcionais de espécies vegetais possuem grande efeito no funcionamento de ecossistemas florestais. Entretanto, o conhecimento das relações entre as características da vegetação com processos relacionados à ciclagem de nutrientes em sistemas em processo de restauração ecológica ainda é incipiente. Investigamos os efeitos de sítios e sistemas de restauração com composição e estrutura contrastantes na produção de serapilheira e na transferência de nutrientes, na fauna associada à serapilheira e na matéria orgânica do solo (MOS). Estudamos um experimento que foi implantando em 1997, no Câmpus da UNESP/FCA, em Botucatu, SP, em dois sítios com distintas características edáficas, sendo um localizado na Fazenda Lageado, que é caracterizado por apresentar textura argilosa e de maior fertilidade (Sítio 1 - Nitossolo Vermelho) e o outro localizado na Fazenda Edgardia, apresentando textura arenosa e menor fertilidade (Sítio 2 - Argissolo Vermelho Amarelo). O experimento foi delineado em blocos ao acaso, com cinco tratamentos (sistemas de restauração) e três repetições, em parcelas de 50 x 50 m (2500 m2). Em cada sítio foram implantados quatro sistemas de restauração, que se diferenciaram pelo número e composição de espécies utilizadas: semeadura direta (SEM), sistema agroflorestal (AGR), comercial para madeira e lenha (CML) e diversificado (DIV). Também faz parte do experimento um sistema controle (CON), em que não foi feito plantio (restauração passiva), e se encontra em processo de sucessão natural. Próximo a cada sítio estudamos também um fragmento de Floresta Estacional Semidecidual, como referência (REF). Caracterizamos todos os sistemas de restauração e a floresta de referência quanto ao número de espécies (riqueza rarefeita), densidade, área basal, porcentagem de indivíduos de espécies que se associam com bactérias fixadoras de nitrogênio atmosférico e porcentagem de indivíduos de espécies decíduas. Os sistemas que produziram maior quantidade de serapilheira e nutrientes, independentemente das condições do sítio, foram o comercial (CML) e o diversificado (DIV), devido, respectivamente, à maior proporção de indivíduos de espécies potencialmente fixadoras de nitrogênio atmosférico e maior riqueza de espécies. O comercial e o diversificado também foram os sistemas que mais se diferiram do controle e mais se assemelharam à referência. Os sistemas de restauração não influíram na estruturação e composição da fauna, tampouco diferiram do controle e da floresta de referência, sendo as condições do sítio e a sazonalidade os principais fatores responsáveis pelas diferenças ocorridas, um reflexo principalmente da umidade do solo e dos teores de P e Ca da serapilheira estocada. Embora nossos resultados indiquem que a riqueza de espécies e a porcentagem de fixadores de nitrogênio possuem forte influência na dinâmica da MOS, seus efeitos foram constatados somente no Sítio 1, devido à maior quantidade de argila; no Sítio 2, a grande quantidade de areia implicou em baixos teores de MOS. No Sítio 1, mesmo que não tenhamos verificado diferenças entre os sistemas de restauração, nossos resultados indicaram que os sistemas comercial e diversificado são os sistemas que mais se parecem com a floresta de referência, destacando-se o consórcio comercial que, além de altos valores de estoques, apresentou semelhanças com a referência nos valores de nitrogênio total, carbono orgânico total, abundância natural de 15N e carbono associado aos minerais (COam). A partir de uma análise integradora dos diferentes processos aqui estudados, nossos resultados sugerem que, em sentido amplo, a utilização de espécies com características particulares (por exemplo, com potencial de se associar com bactérias fixadoras de nitrogênio atmosférico) é tão eficaz na restauração dos processos de ciclagem de nutrientes, quanto sistemas com alta riqueza de espécies.
Functioning of forest ecosystems is greatly affected by composition as well as functional traits of plant species. However, the relationship between vegetation traits with nutrient cycling related processes in ecological restoration is so far under explored in the literature. We investigated the effects of tree species traits on different aspects of nutrient cycling (litter and nutrients production, litter-associated fauna and soil organic matter - SOM) in different ecological restoration systems. We analyzed a long-term experiment implemented in 1997, at the Campus of UNESP/FCA in Botucatu, at two sites with different soil characteristics. Site 1 has a clayey and higher fertility soil (a fertile loamy Ultisol) and Site 2 has a sandy texture and lower fertility soil (Alfisol). The experiment was designed in randomized blocks with five treatments (restoration systems) and three replications in 50 x 50 m plots (2500 m²). Four different restoration systems were implanted at each site. Restoration systems are differentiated by the number and composition of species used: direct seeding (SEM), agroforestry (AGR), commercial timber and firewood and (CML) and diversified (DIV). A control system (CON), with no planting and natural succession processes are following its own way (passive restoration) was also analyzed. Furthermore, we studied a fragment of seasonal semideciduous forest next to each site as a reference (REF). We assessed the number of species (rarefied richness), density, basal area and percentage of nitrogen fixing species and percentage of individuals of deciduous species in all restoration systems and forest reference. Litter and nutrient yield were higher both in the commercial (CML) and diversified (DIV) systems, regardless of site condition, which was due, respectively, to the largest proportion of individuals of putative nitrogen fixing species and higher species richness in those systems. The commercial and diversified systems were also the ones who most differed from the control and were the most similar to the reference. Restoration systems did not influence the soil fauna community structure, neither differed from the control and reference forest, while site conditions and seasonality were the main factors explaining differences, a reflection mainly of soil moisture and levels of P and Ca from litter stock. Although our results indicate that species richness and percentage of nitrogen-fixing species had a major influence on SOM dynamics, this was only observed at Site 1, due to the greater clay content. In Site 2, the high sand proportion resulted in low SOM levels. In Site 1, athought we have not found differences amidst restoration systems, our results indicated that the commercial mixed planting (CML) and diversified (DIV) systems were the most similar ones to the reference forest, especially the COM, regarding total nitrogen, total organic carbon, natural 15N abundance and carbon associated with minerals (COam). By means of an integrative analysis of all processes studied here, our results suggest that the choice of species with particular traits (for example, putative nitrogen biological fixation) are as effective at restoring processes nutrient cycling, as systems with high species richness.
CAPES: 99999.004653/2014-09
FAPESP: 2011/23593-1
CNPq: 14/2011

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Chang, Cheng-Ping, i 張正平. "A Research of Litterfall in Nanjenshan Lowland Rain Forest". Thesis, 1998. http://ndltd.ncl.edu.tw/handle/61870756386900114509.

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碩士
國立臺灣大學
植物學系研究所
86
The purpose of this study is to understand the pattern of litterfall along altitudinal gradient in the Nanjenshan lowland rain forest, and to compare the litterfall from 1992 to 1993 in the Lanjenshi plot. 45 traps were placed systematically along the northwestern ridge of Nanjenshan. All samples were collected monthly and separated into leaves, branches, flowers, fruits, and miscellaneous fractions. Annual litterfall from October 1995 to September 1997 was 11.77 and 9.43 t/ha, respectively, of which 7.96 and 6.43 were leaves, 2.42 and 1.82 woody parts, 0.56 and 0.57 fruits, 0.15 and 0.13 flowers. The annual litterfall was similar with other tropical forests and higher than that of th eLanjenshi plot. The seasonal pattern of litterfall showed two pronounced peaks: during the growth season (from March to May) and the typhoon periods (from July to September). The effect of northeastern monsoon (from October to March) on litterfall was not significant. Leaf-fall can be divided into three patterns: the growth season, the typhoon periods and the northeastern monsoon periods. Except the typhoon periods belonging to the unsteady litterfall pattern, the growth season leaf-fall was the most important pattern. A total of 140 species, belonging to 64 families and 102 genera, were collected. Among them 88 were trees, 11 shrubs, 8 ferns and 33 lianas. The most dominant species was Ficus benjamina (7.89% of leaf litter), followed by Bischofia javanica (6.39%) and Cyclobalanopsis championii (4.15%). Lianas, responsible for about 17.14% of leaf litter, showed tropical characteristics. The dominant species of lianas were Schizostachyum diffusum (4.04% of leaf litter), Schizostachyum diffusum (3.71%), and Erycibe henryi (2.99%). Result of DCA indicated that the traps on transect can be divided into three groups along the altitudinal gradient. This coincides with the three vegetation zones from crown data. The litterfall of valley zone was higher than other zones, and was dominated by Ficus benjamina, Bischofia javanica, Ilex rotunda. The slope zone was dominated by Michelia compressa, Schefflera octophylla and Syzygium euphlebium. On the ridge zone, Cyclobalanopsis championii, Syzygium kusukusense, and Cyclobalanopsis longinux were the dominant species of leaf litter.

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Liu, Xiang Yao, i 劉湘瑤. "Litterfall production and nutrient content in nanjenshan subtropical rain forest". Thesis, 1994. http://ndltd.ncl.edu.tw/handle/48839723173479583665.

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32

Lin, Chin Han, i 林京翰. "Litterfall dynamics of Abies kawakamii Stand at Mountain Hehuan, Taiwan". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/30873028771986407980.

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碩士
國立臺灣大學
森林環境暨資源學研究所
100
Litterfall is one of the important processes in ecosystem studies, which hasn’t been studied on Abies kawakamii forests. Litterfall traps were set up near the tourist center in Xiao-Feng-Ko, Hehuan mountains. Litterfall was collected once every two weeks in 2011. Results showed that annual litterfall was 3129 ±445 kg ha-1 ( mean ± standard error of the mean ), which was composed of foliage ( 69% of total annual litterfall ), branch ( 12% ), bark ( 11% ), reproductive part ( 1% ), and miscellaneous ( 7% ), respectively, showing that foliage was the major path for litterfall. The peak of the litterfall was in November ( 640 kg ha-1, 20.4% of the whole year ) and December ( 507, 16.2% ) of which was composed of foliage mainly ( 86.4% of total litterfall in November, 83.2% of total litterfall in December ). This situation could have been caused by the heavy rain fall, hail fall, cold temperature, or a response to the previous drought in September. The peak of branch fall was in January and February (131 kg ha-1 two-mouths-1, 33.1% of the annual branch litterfall ), which could have been caused by snow and gusty wind. Litterfall ( mainly foliage ) increased a little bit near the timing of new foliage expansion ( late April to early June ), which could have been caused by the heavy rain fall in May, or the regeneration of the foliage. No significant typhoon occurred during study period, therefore, litterfall did not increase during summer season. As to the reproductive part, only a few microsporangia were found on roadside stand during the study period, yet no macrosporangia were found. Therefore, 2011 could be considered as a poor year of reproduction for Abies kawakamii.

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33

Baker, AC. "The dynamics of litterfall in eucalypt woodland surrounding pine plantations". Thesis, 2009. http://hdl.handle.net/10453/28694.

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University of Technology, Sydney. Faculty of Science.
Biological invasions pose one of the greatest threats to global biodiversity and frequently result in the widespread loss of flora and fauna. Biological invasions have become a major focus of ecology in recent decades, and in particular, the invasive species radiata pine (Pinus radiata D. Don) is of considerable concern. Radiata pine has a very limited distribution in the northern hemisphere in its natural range. Its utility in the timber and manufacturing industries, however, has lead to widespread planting, especially in the southern hemisphere, where over 4 million hectares of plantations have been established. In fact, radiata pine is now the most commonly cultivated conifer in the world. A growing body of evidence from studies in the southern hemisphere has shown that pines are spreading invasively beyond the confines of plantations, displacing native species and becoming the dominant species in a number of vegetation types. The negative ecological impacts associated with pine plantations now extend well beyond plantation boundaries. While a number of studies have examined the invasion of individual pines (wildings) from plantations into surrounding vegetation, very few studies have considered the impacts of pine plantations and pine litter on surrounding native plant communities. Pine litter is defined here as structures shed from pines; primarily needles and pollen cones, but also seeds and twigs. In New South Wales (Australia), pine plantations are frequently bordered by native vegetation, providing ideal conditions for pine-litter intrusion to occur. Nevertheless, rates of pine-litter intrusion have never been quantified. Furthermore, the responses of an ecosystem to an influx of pine litter are largely unknown. The aims of this thesis are first to quantify the intrusion of pine litter into native vegetation adjacent to pine plantations and second to determine the impacts of pine litter intrusion on the structure and function of native woodland communities. Fieldwork was conducted at two geographically disparate locations in the Central Tablelands of New South Wales (Australia): Jenolan Caves Karst Conservation Reserve and Gurnang State Forest. At both sites, pine plantations and native woodland are separated by a narrow fire trail that is only a few metres wide. A comparative framework is used, whereby sites in eucalypt woodland that were adjacent to pine plantations (adjacent sites) were compared with sites in eucalypt woodland that were not adjacent to plantations but rather adjacent to eucalypt woodland (reference sites). As the effect of plantations is expected to decrease with increasing distance into native vegetation, sampling plots located at distances of 0, 5, 15, 25 and 50 m from the edge of the native vegetation were established at reference and adjacent sites. This enabled testing of both the impact of plantations on native vegetation, and also the spatial extent of this impact on native vegetation. The first and crucial step in examining the intrusive effects of pine plantations was to quantify the amount of native and exotic litterfall at reference and adjacent sites. At each sampling plot, I measured the amount of native and exotic litterfall (i.e. pine litter intrusion) every 4 weeks for 1 year at Gurnang State Forest and for 2 years at Jenolan Caves Karst Conservation Reserve. Pine needles and pollen cones were found to be a significant component of litterfall in woodlands adjacent to pine plantations. Exotic and native litterfall varied both seasonally and annually. Interestingly, peak needlefall from pines occurred in autumn and winter, which coincided with the minimum native leaffall. Conversely, pine needlefall was at a minimum during summer, during which native leaffall was high. The comparison of two separate woodlands adjacent to plantations revealed similar patterns of pine-litter intrusion although the absolute quantity of pine-litter intrusion was greater at Jenolan compared to Gurnang. Comparison of the carbon (C) and nitrogen (N) content of litterfall revealed subtle yet significant differences between pine and native litterfall. Pine litter generally had a lower N content than native leaffall at Jenolan, but a higher N content than native litter at Gurnang. At both locations, the pine litterfall is additional to native litterfall and as such, pine-litter intrusion is adding additional resources to woodlands adjacent to the plantation. Having determined the rates of pine-litter intrusion, the next step was to determine the fate of pine litter once it had intruded into woodland vegetation. In the absence of fire, plant litter is ultimately broken down through the decomposition process. A three-by-three experimental design was employed, where 3 litter types (pine, native and a 50:50 mix of pine and native litter) were placed under 3 different conditions (‘reference sites’, ‘adjacent sites’, and sites within pine plantations). Litterbags were constructed and filled with a known mass of litter before being placed in the field. Every 8 weeks, for 18 months, litterbags were collected and destructively sampled. Decomposition was measured as a function of weight loss through time, while the corresponding nitrogen and carbon contents were determined. While decomposition was quite slow overall, rates of decomposition were generally faster for native litter than for pine litter. Throughout the experiment, the N concentration of litter increased in all litter types although it was higher in native litter than in pine litter. An important consequence of the slower rate of decomposition of pine litter is likely to be the accumulation of pine litter in woodlands adjacent to plantations. This may have severe implications for the structure and composition of plant communities adjacent to plantations. To test this, I examined the seasonal and spatial patterns of plant community structure of eucalypt woodlands surrounding pine plantations at Jenolan and Gurnang. Eucalypt woodland at Gurnang showed only a minor change in the structure and composition of understorey vegetation at sites nearest the plantation. In contrast, eucalypt woodland at Jenolan showed a much stronger response to plantations, with significantly lower total species richness at adjacent sites compared with reference sites. This resulted in a pronounced ‘edge effect’ up to 15 m into eucalypt woodland adjacent to pine plantations. Canonical correspondence analysis was used to examine the relationship between environmental variables and plant community structure. Pine litterfall explained a significant portion of the variation in plant community structure at reference and adjacent sites at Jenolan, where large quantities of pine litter intrude into native vegetation. At Gurnang, where smaller quantities of pine litter intrude into eucalypt woodland, pine litter intrusion explained a lower portion of the variance between reference and adjacent sites. The plantation at Jenolan consists of large, mature pines that have formed a dense closed canopy, while at Gurnang, the plantation has been established more recently and the pines are not as large, and have not formed a closed canopy. The plantations at Jenolan are therefore a greater source of litter and are also likely to have more pronounced influence on the microclimate compared with the plantations at Gurnang. Lower diversity of flora at Gurnang also may limit the ability to detect differences in plant communities between reference and adjacent sites. Finally, I investigated the impact of pine litter on plant community structure by testing the hypothesis that pine litter facilitates the germination and growth of radiata pine seeds. Using a manipulative glasshouse experiment, radiata pine seeds were sown in pots and exposed to varying quantities of different litter treatments (pine litter, native litter and a 50-50 mix of pine and native litter). The germination and subsequent growth and survival of pines were measured over a period of 2 months. Litter depth but not litter type was found to be an important determinant of pine seedling establishment. With the exception of treatments that were covered by a small layer of litter (i.e. 1 cm) increases in litter depth resulted in delayed and lower rates of seedling emergence. Although pine and native leaves are different shapes (i.e. needle vs. broadleaf) and form very differently structured litter layers (dense mat vs. loosely structured), both litters appear to cause similar physical resistance to seedling establishment. These results indicate that litter accumulation resulting from pine intrusion can alter the establishment of pine seedlings. Given the invasive nature of radiata pine, it is highly likely that increased litter depth resulting from pine-litter intrusion will influence the establishment of many native species. In summary, significant quantities of pine litter were found to intrude into native woodland adjacent to pine plantations, which in turn, appears to be responsible for observed shifts in ecosystem structure and function. This is of particular concern in instances where pine plantations are situated adjacent to native vegetation that has been set aside specifically for conservation purposes. I therefore suggest the provision of a buffer zone around plantations in order to minimise intrusive impacts of plantations on native biodiversity. Whilst this can be achieved using a number of techniques, careful consideration of the structure of native vegetation is needed when selecting the appropriate technique. Having an inappropriate buffer may have an undesirable influence on native vegetation.

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34

Wang, Hsueh-Ching, i 王雪卿. "Patterns of forest biomass and litterfall at different scales in Taiwan". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/61948141450337325992.

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博士
國立臺灣大學
地理環境資源學研究所
103
Forest ecosystem is the major carbon pool in terrestrial biosphere, and understanding dynamics of forest carbon stock and flux is important for carbon budget. This dissertation used remotely sensed imagery to evaluate the pattern of biomass and litterfall in subtropical/tropical forests. The dynamic global vegetation model was also included to model typhoon-induced defoliation and carbon cycle under scenarios of typhoon intensity and frequency. Firstly, this dissertation extracts canopy areas from a high spatial resolution QuickBird image to assess the patterns of carbon stock across topographical gradients and the edge effect in a Chilan montane cloud forest. Mean ( s.d.) carbon per individual was 138  118 kgC with an estimated site carbon density of 119.3 MgC ha-1 in a false cypress (Chamaecyparis obtusa var. formosana, CHFO) cloud forest. The negative trends of temperature and solar radiation along the elevation gradient were observed, and slope played a crucial role in varying CHFO canopy area. The findings suggest that topographical heterogeneity may alter the spatial patterns of nutrients and bioclimate that influence the structure of the vegetation. Secondly, time-series MODIS LST- (land surface temperature) and PV-derived (photosynthetically active vegetation cover) metrics were used to derive litterfall. The mean annual litterfall was 5.1 ± 1.2 Mg ha-1 yr-1 in Taiwan montane forests. The temporal dynamics of the litterfall revealed that typhoons and consecutive drought events might be important for temporal variability of litterfall. The elevation gradient and aspects were critical to dominate spatial patterns of litterfall. Thirdly, a wind built-in function with wind speed, temperature and precipitation variables was developed in a dynamic global vegetation model Hybrid v4.2 to simulate typhoon-induced leaf litter in the Fushan experimental forest. The modeled and observed leaf litter was significant correlation (r2 = 0.33, p < 0.001) with moderate underestimation (15.6%). The leaf litter, leaf area index (LAI), total biomass, gross primary production (GPP) and net primary production (NPP) were higher in non-typhoon environment than in typhoon-affected environment. The raises of typhoon intensity and frequency would increase leaf litter and soil respiration resulting in the decreases of LAI, biomass, GPP and NPP. If the substantial defoliation from more intense or frequent typhoon might affect regional carbon budget at long-term time scale. Overall, using satellite images and a dynamic global vegetation model to monitor spatial and temporal patterns of living biomass, litterfall and carbon flux may facilitate monitoring and predicting of carbon budget and perturbations in forest ecosystems.

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Hwang, Yen-Chi, i 黃彥綺. "Dynamics of Litterfall at Houlong and Shihu Coastal Plantations in Taiwan". Thesis, 2007. http://ndltd.ncl.edu.tw/handle/66114003114117124082.

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碩士
中興大學
森林學系所
95
The purpose of this study was to treat the litterfall dynamics at Houlong and Shihu coastal plantations in western Taiwan. The litterfall was collected once a month for 12 months. In addition, to understand the relationship between leaf area index (LAI) and litterfall, we used hemispherical photographs to evaluate LAI at the beginning of a month and collected litterfall at the end of a month. Furthermore, we combined the climate information to acquaint the influence of climate factors (precipitation, temperature, wind velocity) on litterfall and LAI dynamics. The results showed that the highest annual total litterfall was in Upland of Shihu (C. spp. and Hibiscus tiliaceus mixed plantation) (11,845 kg ha-1 yr-1), the lowest was in Casuarina spp. plantation of Houlong (6,590 kg ha-1 yr-1). This diversity should be the result of difference in stand and environment conditions. Although Upland and Lowland were equally C. spp. and H. tiliaceus mixed plantations in Shihu, the litterfall type between them were different, probably indicate that because passed through tree decay and artificial replanting, the importance of dominated tree species had changed definitely, hence have developed unlike models of the litterfall production. In the dynamics of total litterfall and litterfall components, there were seasonal variations and leaf was the basis. Nutrient content of most elements and litterfall have alike variational trends. Above-mentioned results exhibited that leaf had the conclusive influence on total litterfall and nutrient content. Among of the climate factors, major effect on litterfall was precipitation, but had to depend on locality and stand. Litterfall had higher nutrient concentration during autumn and winter; however, the action of special factors (reproduction and fresh litterfall, leaching, salt mist) made the final nutrient concentration in litterfall slightly different from this trend. The LAI variation increased during spring and summer, but decreased during autumn and winter. As a whole, the litterfall dynamics were mainly influenced by precipitation and salt mist, but litterfall caused by environment impact without senescent process and those from reproductive parts with higher nutrient were also important, and precipitation also controlled the LAI variation. Consequently, precipitation may be concluded as an important effect factor of nutrient recycling in Houlong and Shihu coastal plantations.

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36

Gillman, Lennard N. "Microdisturbance to forest seedlings in New Zealand due to litterfall and animals". 2002. http://hdl.handle.net/2292/1708.

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Whole document restricted, see Access Instructions file below for details of how to access the print copy.
Natural and artificial seedlings were monitored for damage by litterfall and animals over two years in five temperate forests in the North Island, New Zealand. Mortality was also recorded for natural seedlings. Two of the forest sites were Agathis australis/mixed angiosperm forest (Huapai and Cascades), two sites were mixed podocarp/angiosperm forest (Pureora and Ohakune), and one site was Nothofagus forest (Rotokuru). Litterfall damage rates of natural seedlings were similar to those of nearby artificial seedlings, and site means for the two were highly correlated (R2=0.95, P<0.005). However, there was no relationship found between non-trophic animal damage (damage without consumption) to natural seedlings and animal damage to artificial seedlings. Nor was there any correlation between artificial seedling damage, due to animals or litterfall, with natural seedling mortality. Artificial seedlings should not therefore be used to estimate seedling mortality due to microdisturbance. Monitoring natural seedlings enabled non-trophic animal damage to be readily detected and provided additional information on animal-plant interactions. The value of using artificial seedlings is that they provide a measure of the litterfall disturbance potential that is independent of the patchy distribution of natural seedlings within safe sites, and independent of species specific resistance to damage. An important proportion of the natural seedlings damaged at Huapai was due to non-trophic damage by animals (21.4%/yr.). Most of these seedlings were bitten off at the base and left uneaten and the remainder were uprooted. Non-trophic damage to seedlings by animals was negligible at the other four sites. However, a high proportion of palatable species were damaged at the two sites managed as restoration areas (Pureora and Rotokuru) by the Department of Conservation. Litterfall was the cause of an important proportion of the seedling mortality at each forest site (11-18%) except Cascades (2.4%), and it was an important cause of seedling damage at all sites. Annual litterfall damage to artificial seedlings at Huapai was greater than at any other site, and similar to that reported for several tropical forests. Macro-litterfall (>30x1.5 cm) surface area and macro-leaf-fall weight were both correlated with litterfall damage to artificial seedlings (R2>0.96, P<0.005 for both), but total macro-litterfall weight (ie. including deadwood) was not. This suggests that the rate of macro-leaf-fall is the primary factor that determines the litterfall damage regime. Macro-leaf-fall is in turn influenced by climate, because both the abundance of large leaved species and their productivity are linked to climate. However, protective vegetation within 2 m of the ground can reduce the risk of seedling damage by up to 75%. At Huapai and Pureora the rate of damage to artificial seedlings under different species combinations were compared. At Huapai, the risk ranged from 39%/yr beneath canopies with both Agathis australis and Cyathea dealbata down to 2%/yr beneath canopies without A. australis, C. dealbata, or Rhopalostylis sapida. At each site 20 seedling pairs of the two most abundant seedling species were selected. One of each pair was experimentally damaged by pinning to the ground in order to simulate litterfall damage. Pinned seedlings had a higher mortality over two years than the unpinned control group. However, resilience to damage, in terms of survival and height regained, varied substantially between species. Unexpectedly, pinned Nothofagus menziesii and Hedycarya arborea seedlings grew much faster in response to damage than nearby unpinned seedlings of the same species. Heterogeneity in litterfall risk among microsites, and differential resilience to litterfall damage among seedling species, indicates that some species have a greater chance of surviving litterfal in particular microsites than others. The litterfall damage regime, therefore, has the potential to contribute to regeneration niche differentiation and may thereby contribute to plant species richness.

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37

Abelho, Maria Manuela Correia. "Once upon a time a leaf... : from litterfall to breakdown in streams". Doctoral thesis, 2000. http://hdl.handle.net/10316/2143.

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Tese de doutoramento em Biologia (Ecologia) apresentada à Fac. de Ciências e Tecnologia da Univ. de Coimbra
Os ribeiros de floresta são basicamente heterotróficos, i.e., obtêm a maior parte da sua energia do ecossistema que os rodeia. A matéria orgânica alóctona produzida na floresta adjacente entra no rio, é retida e decomposta in situ, fornecendo energia para todo o ecossistema. As cadeias alimentares dos ribeiros de floresta são pois baseadas na decomposição microbiana da matéria orgânica alóctona, principalmente folhas. Os fungos, em particular os hifomicetos aquáticos, são os principais decompositores de folhas em rios. Os hifomicetos aquáticos colonizam as folhas acelerando a sua degradação através de um efeito directo no tecido foliar e indirectamente por aumentarem a palatabilidade dos detritos para os detritívoros. Os detritos são finalmente fragmentados em pedaços progressivamente mais pequenos através da actividade alimentar dos macroinvertebrados e da abrasão física. Os ribeiros de floresta são pois diferentes da maior parte dos ecossistemas no sentido em que obtêm a maior parte da sua energia através da decomposição de matéria orgânica alóctona. O objectivo desta tese é a elucidação de alguns dos aspectos da decomposição de folhas em ribeiros de floresta, com ênfase no papel dos microorganismos no processo. A tese cobre a ligação entre o ribeiro e a floresta circundante, i.e., a entrada de matéria orgânica alóctona no sistema, assim como o destino das folhas dentro do ribeiro. Os resultados obtidos mostram que as generalizações obtidas em ribeiros de outras áreas geográficas são aplicáveis a ribeiros de floresta da zona temperada/mediterrânea: (1) a matéria orgânica alóctona é a principal fonte de energia em ribeiros de florestas caducifólias mistas locais, a maior entrada de matéria orgânica ocorre no Outono e é composta maioritariamente por folhas, (2) a importância relativa dos factores determinantes das taxas de decomposição varia em função de um extenso conjunto de factores internos e externos e (3) os fungos são os principais decompositores microbianos de folhas em rios, pelos menos em termos de biomassa. Os resultados desta tese mostram também que existe um gradiente latitudinal geográfico nas taxas de decom-posição de folhas em rios devido ao desenvolvimento mais rápido (em termos de biomassa) dos decompositores microbianos nos rios tropicais.

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38

Lin, Yen-Zhen, i 林嬿真. "Dynamics of Litterfall of Cryptomeria japonica-Chamaecyparis Formosensis Plantation 7 years after Thinning". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/97565839324032134936.

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碩士
國立宜蘭大學
森林暨自然資源學系碩士班
102
The objectives of study were to examine mass recycling of 51 year-old Cryptomeria japonica- Chamaecyparis formosensis plantation with 3 thinning regimes by low thinning method in Taiping shan area. The results showed that thinning reduced litterfall amount significantly during 7 years after thinned. Mean annual litterfall amount were 1215.0±368.5 kg ha-1 yr-1 in unthinning stand, 992.1±370.6 kg ha-1 yr-1 in weak thinning stand and 972.6±387.4 kgha-1 yr-1 in moderate thinning stand. But there were no significant difference between weak and moderate thinning intensity stand. Litterfall amount of stands8 years after thinned was much than that 7 years after thinned caused by successive typhoon in summer. Leaf fall was the main component of litterfall, especially, leaves of Cryptomeria japonica and Chamaecyparis formosensis, the main canopy species. After thinned, annual leaf fall of Chamaecyparis formosensis was lower than unthinning stand, and there were no significant difference between the two years; Annual perennial organ mass , and leaf fall of Cryptomeria japonica 8 years after thinned was much than that 7 years after thinned caused by typhoon , but there were no significant difference among thinning treatments. Annual propagules mass, and leaf fall of hardwood between thinning treatments and two years were no significant difference. Litterfall amounts were reduced after thinned, but all had same seasonal change. In early spring, litterfall amount slightly increased because new leaves began expand. In winter, the peak leaf fall amount large came mainly from the leaf fall of Chamaecyparis formosensis which caused by cold-temperature. The increase of branches litter amount was due to typhoon and caused that a positive correlation between branch litter amount and monthly precipitation. By the proportion of the annual litterfall and dry mass of forest litterlayer estimated litterfall decomposition constant. Seven years after thinning, there was no significantly different between 3 thinning regimes. Decomposition constant on average was 0.267 and decomposition time was 3.75 years. As the results, the canopy was recovered 7 years after thinning. There were no significant with litterfall decomposition rate, although the amount of litterfall was decreased after thinning.

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39

Huang, Siao-Cian, i 黃筱茜. "Fine root, Litterfall and Litter Layer Dynamics of Natural Hardwoods in Central Taiwan". Thesis, 2012. http://ndltd.ncl.edu.tw/handle/43940705228135928001.

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碩士
國立中興大學
森林學系所
100
The purpose of this study was to investigate fine root biomass, litterfall and litter layer of three natural hardwoods, Mt. Peitungyen, Hui-sun experiment forest and Lienhauchi in central Taiwan from June 2011 to May 2012. Fine root biomass was the highest in Hui-sun experiment forest (2.02 Mg ha-1), following in Lienhauchi (1.81 Mg ha-1) and the lowest in Mt. Peitungyen (1.52 Mg ha-1). Fine root turnover rate was the highest in Hui-sun experiment forest (0.91 y-1), and the lowest in Mt. Peitungyen (0.68 y-1). In 2010, annual litterfall mass in Mt. Peitungyen, Hui-sun experiment forest and Lienhauchi were 6.34, 12.22 and 9.62 Mg ha-1 yr-1, respectively, increased with decreased elevation and were 5.23, 6.43 and 10.15 Mg ha-1 yr-1, respectively in 2011. Litter was the highest in Hui-sun experiment forest (14.07 and 14.00 Mg ha-1, respectively in 2010 and 2011). Decomposition constant increased (0.73, 0.87 and 1.09, respectively) with decreased elevation in 2010, but decomposition constant was 0.50, 0.46 and 0.96 in 2011, indicating decomposition rate decreased in 2011. Results showed that annual litterfall mass increased with decreased elevation, but litter layer was on the contrary. Increased fine root production and biomass resulted in fine root turnover increased, accelerated nutrient cycling in Hui-sun experiment forest.

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40

Wang, Jing-Li, i 王靜莉. "Litterfall Dynamics in a Yellow Cypress Forest at the Chi-Lan Mountain Site". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/37747193009593325738.

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碩士
國立東華大學
自然資源與環境學系
99
Litterfall is the main pathway of internal nutrient cycling in forest ecosystems. From August 2003, aboveground litterfall was monitored in a yellow cypress (Chamaecyparis obtusa var. formosana) forest at the Chi-Lan Mountain site, northeastern Taiwan. The litterfall was collected biweekly using 10 litter traps installed systematically in the stand. From 2004 to 2010, annual litterfall averaged 3,687 kg ha-1 yr-1 (ranged between 2,489- 5,757 kg ha-1 yr-1), where the leaf litter contributed the greatest proportion with an average of 76.7% (ranged between 66.1-86.0%). The annual patterns of total litterfall showed two marked seasonal peaks. The summer peak (from July to October) was caused by typhoon. Woody litter (branch, bark) fell more irregularly through the year, which peak fall varied with typhoon. The winter litterfall peak (from November to December) was caused by leaves. Sexual organs (flowers, fruits, seeds) mainly fell from March to May, while miscellaneous litterfall (mosses, insects) fell irregularly throughout the year. Typhoon disturbance strongly affected annual litterfall input, which contributed an average of 37% of the annual litterfall mass (ranged between 13-73% ).

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41

Chen, Jia-Huey, i 陳佳慧. "Dynamics Changes of Litterfall and Soil Nutrient Content at Different Stands in the Guandaushi". Thesis, 2000. http://ndltd.ncl.edu.tw/handle/29879496815655198976.

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碩士
國立中興大學
森林學系
88
The monthly amount of litterfall, decomposition rate of litter layer and soil nutrient pool of three different stands (natural hardwood stand, NS; secondary hardwood stand, SS; and China-fir plantation stand, CPS) in the Hui-Sun Experimental Forest were monitored from Sep. 1998 to Aug. 1999 by using littertrap and litterbag approaches respectively. We also used data loggers to collect the temperature in the soil layers. The results showed that the amount, one yearly basis, of litter of NS (7,098.9 kg/ha) was the highest followed by SS (6,721.5 kg/ha), CPS which amounted to 4,659.5 kg/ha was the lowest. The amounts of litterfall varied significantly with month and indicated that litter productions showed two peaks during one year. One was in typhoon season (Aug.-Sep.), and the other was in growth season (March-Jun.). The litterfall of which 52.5-61.2 % was composed of foliar litter, 24.3-39.8 % was branch, 6.5-14.5 % was reproduction, and the remainder (1.2-5.8 %) was comprised of other plant materials. Annual amounts of these nutrients included 1.96-2.89 t/ha C, 49.1-1.3.3 kg/ha N, 3.89-8.94 kg/ha P, 24.67-68.31 kg/ha K, 22.91-61.86 kg/ha Ca, and 9.12-18.31 kg/ha Mg, respectively. Total nutrient input from litterfall were NS> SS> CPS. With respect to the decomposition litter collected from NS showed the highest rate during the initial stage (60-254 days), followed by those from SS and CPS. However the rate of litter decomposition collected from CPS became the highest. The mass remaining of litter collected from CPS was 69.5% lower than those from SS (70.52 %) at 254 days, and they were 55.94 %(CPS), 66.54 %(NS), and 61.97 %(SS) at 316 days, respectively. During the study, the trend of the percentages of nutrients remaining of C and Mg increased initially but than decreased, and N and P increased until the study end, and K and Ca decreased initially but than increased. Nutrient content of litter layers in NS was higher than that in SS and CPS, except that Ca was highest in SS. Litter layer nutrient pool were C: 7.73-24.57 t/ha; N: 352-1,312.3 kg/ha; P: 51-262.6 kg/ha; K: 289.7-1,736 kg/ha; Ca: 48.4-407.1 kg/ha; Mg: 29.8-124.8 kg/ha, respectively. Nutrient content of soil layer in NS was also higher than that in SS and CPS, except that K was highest in CPS. Layer nutrient pool were C: 110.56-158.96 t/ha; total N: 4.94-8.06 t/ha; total P: 1.04-2.52 t/ha; total K: 31.97-96.67 t/ha. The available nutrient exist in soil layer were extractable K: 350.07-451.34 kg/ha; extractable Ca: 134.99-481.98 kg/ha; extractable Mg: 78.24-98.95 kg/ha, respectively。 The fluctuations of soil temperature were regular in different soil layers. The lowest temperature was at Feb. and the highest one was at Aug. During fall to winter (from Oct. to Fed.), the temperature at 20 cm depth was higher than at 10 cm depth and at the surface. But when spring began, the temperature at the surface was higher than 10 and 20 cm depth.

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42

Lu, Shu-Wei, i 呂淑瑋. "Nutrient Accumulation and Litterfall Return of Natural Hardwood among Different Elevation in Central Taiwan". Thesis, 2010. http://ndltd.ncl.edu.tw/handle/24570383747085321129.

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碩士
國立中興大學
森林學系所
98
The purposes of this study were to evaluate the internal nutrient cycling of litterfall at different elevation (temperature and rainfall) sites. Litterfall was collected monthly by traps and litter was collected trimonthly in three natural hardwood, Mt. Peitungyen (2,078 m), Hui-Sun experiment forest (1,066 m) and Lienhauchi (782 m) in central Taiwan. Monitoring litterfall amounts, nutrient flux, litter amounts and nutrient accumulation of the three sites from March 2009 to February 2010. Annual litterfall mass and decomposition constant increasing (6,583.2 to 9,180.6 kg ha-1yr-1 and 0.49 to 0.87, respectively) with decreased elevation (increasing temperature). The amount of reproduction was higher (1,031.7 kg ha-1 yr-1) in Mt. Peitungyen than in Hui-Sun experiment forest (788.2 kg ha-1 yr-1) and Lienhauchi (533.0 kg ha-1 yr-1). Nitrogen and potassium concentrations of branch and leaf were the highest in Lienhauchi. The nutrient input by litterfall increased with decreasing elevation. Using the minimum nitrogen and phosphorous concentrations in the fall leaf as the retranslocation thresholds, indicating nitrogen retranslocation was incomplete in the three sites, but phosphorous retranslocation was complete. These results suggested that phosphorous was the limiting nutrient in the three sites. Calcium, potassium, magnesium input to the forest via litterfall corresponds to the exchangeable stock in the top 60 cm soil were the highest in Hui-Sun (14.33%) and the lowest in Mt. Peitungyen (6.23%).

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43

Lee, Chia-ling, i 李佳玲. "A Research of Litterfall in Warm-temperate Evergreen Broad-leaved Forest in Chungtzekuan area". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/23211567817388919482.

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碩士
國立臺南大學
自然科學教育學系碩士班
94
A 2-ha permanent plot is 200 m long and 100 m wide at Chungtze Kuan area of southern Taiwan and is dominated by Fagaceae and Laurceae. The purpose of this study is to understand the pattern of litterfall in different habitats. 40 traps were placed systematically along the transet from east to west in the plot. All samples were collected monthly and seperated into leaves, branches, flower, fruit, buds and miscellaneous fraction. Annual litterfall from January 2004 to December 2005 was 3.4 t/ha and 5.01 t/ha, respectively, of whith 2.24 and 3.32 t/ha were leaves, 0.49 and 1.02 branch, 0.16 and 0.2 flowers, 0.12 and 0.11 fruit, 0.19 and 0.23 buds. The seasonal pattern of litterfall showed two pronounced peaks : during the growthy season and the typhoon period. According to the types of litterfall, trees could be divided into spring-falling, autumn-winter-falling, typhoon, double peaks and general patterns. Typhoons made branches fall in larger amounts in July and August, but leaves were not apparently affected. A total of 87 species,belonging to 42 families and 69 genera, were collected. Among thern 75 were tree, 11 lianas and 1 fern. The dominant species was Cyclobalanopsis longinux (21.68％ of leaf litterfall), followed by Machilus thunbergii (17.17％）and Castanopsis carlesii (13.10％）. The litterfall showed no significance difference in three habitats, but increased by altitude. Compared to the other studies, the litterfall of Chungtzekuan area is lower than the other broad-leaved forest, except Chi-lan mountain and Hui-sun experimental forest in Taiwan.

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44

Chu, Hui-Chun, i 朱慧君. "Estimation of nutrient storage and fluxes of litterfall in a yellow cypress forest ecosystem". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/32195852796082995139.

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碩士
國立東華大學
自然資源管理研究所
93
In forest ecosystems, litterfall is the main pathway of internal nutrient cycling. The purpose of this study was to estimate the fluxes of litterfall and the nutrient storage in the yellow cypress stand at the Yunayang Lake site in northeastern Taiwan. Th litterfall was collected biweekly from August 2003 to December 2004 using 10 litter traps installed systematically in the stand. The annual litterfall during this period was 5,900 kg ha-1 y-1, about 80% of which was contributed by yellow cypress. The leaf-fall is the largest portion (73.7%) of litterfall. Typhoon was an important factor of the quantity and quality of the litterfall. During the study period, litterfall was increased by 70% due to the typhoons. There was no significant seasonal variation of the element concentrations in the litterfall. However, when typhoon attacked the site, the nutrient concentrations of the litterfall were raised. The total nutrient fluxes of litterfall were 3,059 kg ha-1 y-1 for C, 50 kg ha-1 y-1 for N, 78 kg ha-1 y-1 for Ca, 9 kg ha-1 y-1 for K, 8 kg ha-1 y-1 for P, 7 kg ha-1 y-1for Mg and 0.2 kg ha-1 y-1 for Na. The below-ground biomass was investigated by excavating 3 yellow cypress trees and by digging 10 subplots (L * W * D = 30 cm * 30 cm * 40 cm). The stand-scale fine root biomass was estimated using the results from the 10 subplots. The stand-scale coarse root biomass was derived from an exponential relationship between DBH and the mass of coarse root of the 3 sample trees. The total below-ground biomass of yellow cypress was 76,600 kg ha-1. The biomass of coarse root was 70,400 kg ha-1. The biomass of fine root was 6,200 kg ha-1. The biomass of fine root of yellow cypress tended to decrease with soil depth. The element concentrations of fine root were larger than those of coarse root. The total nutrient storage of below-ground were 36,095 kg ha-1 for C, 163 kg ha-1 for N, 135 kg ha-1 for Ca, 114 kg ha-1 for K, 40 kg ha-1 for P, 16 kg ha-1 for Mg and 2.96 kg ha-1 for Na. The total above-ground biomass of yellow cypress was 140,400 kg ha-1. The biomass of stem was 106,400 kg ha-1. The biomass of branch was 16,900 kg ha-1. The biomass of leaf was 17,100 kg ha-1. The total nutrient storage of above-ground were 69,895 kg ha-1 for C, 320 kg ha-1 for N, 424 kg ha-1 for Ca, 192 kg ha-1 for K, 77 kg ha-1 for P, 40 kg ha-1 for Mg and 2.99 kg ha-1 for Na. The total biomass of yellow cypress was 217,000 kg ha-1. The total nutrient storage of yellow cypress were 107,124 kg ha-1 for C, 512 kg ha-1 for N, 570 kg ha-1 for Ca, 307 kg ha-1 for K, 120 kg ha-1 for P, 57 kg ha-1 for Mg and 6.6 kg ha-1 for Na.

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45

Chin, Chieh-Chih, i 金絜之. "Study on the Spatial and Temporal Change of Litterfall in Nanjenshan Lowland Rain Forest". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/98662780568237601521.

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碩士
國立屏東科技大學
森林系所
96
Lowland rainforests consist of abundant wildlife species and complex components; litter fall is an important source of nutrition for the lowland rainforests without any artificial management. The litterfall has been an important parameter in ecological research for decades because it can help to understand the function and structure of an ecosystem, also to estimate forest productivity, regeneration and biomass as well. The main composition of litterfall includes foliage, flower, bark, and fruit. The composition of canopy includes branches and foliage. There is a positive relationship between quantity of foliage and litterfall of foliage. The quantity of foliage could be represented by Leaf Area Index (LAI). The data used in this study consisted of the measurements of the litterfall quantity and variety from 1999-2007 to analyze the variation of litterfall based on the effects of season, long term and wind disturbance. In addition, a discussion on the relationship between litterfall quantity and LAI was also conducted. The study result has shown that there was a significant relationship between litterfall quantity and LAI. Also, a predicting model of litterfall by the explanatory variable of LAI was established with R2=0.57. The average quantity of litterfall was 5.52±0.07 t ha-1yr-1 in these 8 years study period in Nanjenshan area. Different terrains in Nanjenshan area would have different quantity of litterfall, such as: 6.48±1.57 t ha-1yr-1 in the valley, 5.16±0.64 t ha-1yr-1, in the leeward site and 4.56±0.29 t ha-1yr-1 in the windward site. As to the growth and renew of the vegetation, it was the best in the valley, then followed by the leeward site, and the last was the windward site. The seasonal variation of litterfall quantity has shown two peaks in Nanjenshan areas, which were from February to March and from July to August. The results have also shown that where a large quantity of branches litterfall was during northeastern monsoon at windward site. Therefore, the northeastern monsoon would not have significant effect on the quantity of branches litterfall. The disturbance of typhoon is the most affective factor for the long term variation of litterfall in Nanjenshan area. The forests of this area have not yet been restored completely ever since. By integrating the results of this study and those of previous studies in the references, it can be conjectured that forests could be restored within 1 year if there is not any serious disturbance occurred. However, if the forests are disturbed by severe and continuous typhoons, they would need 3 years for restoring their productivity.

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46

Chang, Chia-Ling, i 張嘉玲. "Dynamic of Litterfall and Its Nutrient Contents at Different Stands in Hui-Sun Experimental Forest". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/79695509037174651068.

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碩士
國立中興大學
森林學系
93
In this study, the monthly amounts of litterfall, including leaves, branches, propagules and other materials were collected by using litterfall trap method in three different stands (natural hardwood, NS; China-fir plantation, CPS; and secondary hardwood, SS), located at Hui-Sun Experiment Forest. They were monitored from Nov. 2003 to Apr. 2005 to explicate how the seasonal and monthly changes in litterfall amounts, contents and composition. The dynamic of litterfall nutrients concentration and input in different stands from Jan, 2004 to Dec, 2004 were also investigated. During the period of investigation, The results showed that the highest amount of litterfall was the NS (10.62 t/ha), followed by SS (9.15 t/ha), and that of the CPS (4.52 t/ha) was the lowest. Among the seasonal variability of litterfall amount in different stands, NS and SS were uni-modal distribution pattern, centered in May – July, but in CPS was twin peaks modal distribution pattern, centered in May-July and September respectively.In this study period, the amount of litterfall reached to the peak in June in NS and SS, due to the double effects with strong typhoon ”Minduli” on June and growing season( March-June). Most of the litterfall in three different stands were composed of leaves (61.0 % - 71.0 %), followed by branches (6.2 % - 13.0 %), reproduction (10.0 % -12.6 %)and others（10.2 % - 14.1 %）. All nutrients concentration of litterfall was in the order as C>N>K>Ca>Mg>P in three stands. The highest amount of nutrients returned to the soil through litterfall among three different stands was SS, followed by NS and CPS, respectively. The amount of annual nutrients input in NS and SS were in the order as C>N>K>Ca>Mg>P, that in CPS was C>N>Ca>K>Mg>P。

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47

Hsiao, Yi-Ju, i 蕭怡茹. "Dynamics of Litterfall of secondary forest, Japanese cedar plantation and bamboo plantation in the Wulai Area". Thesis, 2005. http://ndltd.ncl.edu.tw/handle/79315651690958226249.

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碩士
國立臺灣大學
森林學研究所
93
In order to understand the organization of flux from the canopy to soil in 3 forests, this study monitored litterfall dynamics of secondary forest, Japanese cedar plantation, and bamboo plantation in the Wulai area of northern Taiwan from February 2002 to January 2003. Litterfall was collected once a month for 12months (from February, 2002 to January, 2003). Results showed that annual litterfall was 7.13 t/ha/yr, 5.23 t/ha/yr, and 3.67 t/ha/yr for secondary forest, Japanese cedar plantation, and bamboo plantation, respectively, showing these three stands, leaf, which made up 62.2%, 76%, and 55.1% of annual litterfall, was the dominant component of litterfall. In all three stands, there was a litterfall peak flux occurred in July, 2002, resulting from typhoon disturbance, causing massive amount litterfall. In addition, another litterfall peak of secondary forest and bamboo plantation occurred in the growing season in March, 2002, because a large number of old leaves were replaced by new leaves. Furthermore, in Japanese cedar plantation, its secondary peak of littterfall was caused by the thinning treatment in November, 2002. This study clearly showed that litterfall for 3 stands in Wulai area were affected by the phenology of dominant trees, as well as typhoon and human disturbance.

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48

Liao, Jiung-Hao, i 廖駿豪. "The relationships between litterfall and soil dynamics on Kenting Uplifted Coral Reef Nature Reserve Forest Ecosystem". Thesis, 2006. http://ndltd.ncl.edu.tw/handle/61193690817752553639.

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碩士
國立屏東科技大學
環境工程與科學系
94
The Kengting Nature Reserve of Uplifted Coral Reef (KNROUCR) is the largest in area and well protected area for tropic evergreen broad-leaved rain forest in Taiwan. The long-term plot of 10 ha was divided into four habitat types with different species compositions: the autum maple tree (Bischofia javanica)- Taiwan nato tree (Palaquium formosanum) type on the flat terrace whereas was designed as habitat A in this study; the sappan wood (Aglaia formosana) – pouteria (Pouteria abovata) type on the ridge of exposed coral reef, designed as habitat B; the eleplant’s ear (Macar tanarius) – konishi cryptocarya (Cryptocarya concinna) type on the sedimentary basin, designed as habitat C; the pisonia tree (Pisonia umbellifera) type at the bottom of valley, designed as habitat D. Litter productions, and leaf litter decomposition , soil microbial biomass C and N(MBC and MBN), carbon and nitrogen mineralization, and the compositions of soil solution were monitored for 2-year period (Feb. 2004-Feb. 2006) in the four habitats . The aims of this study in the KNROUCR were conducted: (1) to investigate the litter inputs and leaf litter decomposition process in relation to plant habitat types and seasons, (2) to explore the soil organic matter mineralization, (3) to illustrate the influence of soil microbial biomass on the litter decomposition dynamics, and (4) to explore the bioavailability, seasonal dynamics, and flux of soil nutrients. Experimental results indicated that litterfall in all habitats shows a marked seasonal pattern, with the lowest amounts in spring (0.34-0.54 ton/ha/month) and the highest amounts in the summer (0.81-1.32 ton/ha/month) and winter (0.49-0.69 ton/ha/month) seasons because of typhoon and monsoon. In addition, the litterfall production in habitats A and D was significantly (p<0.05) greater than in habitats B and C. It is probably because the dominant tree species of habitat B are relatively adapted to strong wind, and the leaves survived long on the exposed rock; habitat C was secondary forest which dominated by early succession tree species with lower leaf area index. The litter remaining mass percentage in the first year was from 50% to 45.6%, however in the second year was from 25.8% to 18.2%. The litter remaining mass percentage in the 2nd year was lower than 1st year, because of the larger rainfall from frerquent typhoon events in the 2nd year. Nevertheless, the Olson’s decomposition parameters (k and t50) between the leaf littes of four habitats were not significant. Overall, the leaf litter decomposition rate followed the order by Ca > Mg >N> Na > K > P > mass > C. Additionally, the annual return of nutrient followed the order by C (221-4483 kg/ha) > Ca (160-324 kg/ha) > N (58.6-123 kg/ha) > K (24.7-41.7 kg/ha) > Mg (16.2-30.6 kg/ha) > Na (5.35-25.0 kg/ha) > P (0.16-1.95 kg/ha). The surface soil (0-15 cm) MBC ranged in 477-1135 mg/kg in each habitat, whereas is higher than those in general tropical forests (149-667 mg/kg), however, the MBN ranged in 65.7-81.0 mg/kg, whereas is similar to those in general tropical forest (38.0-78.0 mg/kg). The rate of C mineralization (the amount of CO2-C production) ranged in 25.0-36.0 g CO2-C/kg/yr, which is not different from tropical and subtropical forests, however, the rate of C mineralization C in the 2nd year was 4-5 folds than that in the 1st year, because of the dramastic change in soil hydrology in altering doiminant microbes. The NO3--N/NH4+-N ratios ranged in 3-4, and N mineralization, ammonification, and nitrification ranged in (-0.12)-(0.09), (-0.04)-(-0.02), and (-0.27)-(0.08) mg/kg/d. The order of cation concentration in the soil solution is Ca > Si > K > Na > Al > Mg> Fe > NH4 > Mn > Zn > Cu, and it of anion is Cl > SO4 > NO3, respectively. Overall, the input of C and N was much more than the within the study area, so that the forest ecosystem keeps in dynamic balance.

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49

Ma, Shah-Mu, i 馬仕穆. "Using SPOT Remote Sensing Image to Estimate Leaf Area Index and Litterfall in Nanjenshan Forest Ecosystem". Thesis, 2000. http://ndltd.ncl.edu.tw/handle/37986037508881371393.

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碩士
國立屏東科技大學
熱帶農業研究所
88
Leaf Area Index (LAI) and Litterfall are important factors for determining the nutrient cycle in forest ecosystem. Traditional investigation of Leaf Area Index and Litterfall not only requires a great deal of time and manpower but also fails to estimate the spatial distribution. In this study, we integrate the Vegetation Index (VI) of SPOT image with the ground surveying data of LAI and Litterfall to construct a simulating model for the Nanjenshan forest ecosystem, which takes into the account of the spatial and temporal variations. The study area is established at the site of the Nanjenshan long-term forest ecosystem. At the test site, 35 litterfall collecting nets (50cm ×50cm) in the different forest types (Leeward, Windward, Valley) were set up to collect the litterfall and CI-110 (Digital Plant Canopy Image Analysis) was used to measure the value of LAI. The VI at the test site was measured by using SPOT remote sensing image of Nanjenshan and the image was analyzed with IDRISI software. Geographical Positioning System (GPS) was also eagle-eyed to determine the geographical coordinates at each sampling plot. Oneway-ANOVA and t-test were used to analyze the seasonal variance of LAI and Litterfall in forest types. Using the regression analysis, the relationship among LAI, Litterfall and VI was determined. The results are summarized as follows: The LAI of Nanjenshan was 3.297±0.096. In the winter, the variation of the forest types was significantly different. The Litterfall of that area was estimated at 5.87ton/ha/yr, and the Litterfall in the Valley was greater than that of the forest types. The LAI-VI regression equation was LAI=4.4297NDVI0.4332(R2=0.557). The equations for different forest types are presented as follow: Leeward {㏑(Litterfall)=4.937+0.242LAI (R=0.379)}; Windward {㏑(litterfall)=5.148-0.023PVI+1.023㏑LAI+0.018DVI(R=0.703)}; Valley{㏑(litterfall)=1.79-0.041WDVI +1.75㏑PVI (R=0.53)}. Based on the available remote sensing images and the estimated LAI, the spatial and temporal variations in LAI and Litterfall can be determined. This can be used as sequence for simulating ecological processes, which will be of great value to long-term ecological study.

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50

Berry, Melissa. "Effects of climate change across seasons on litterfall mass and chemistry in a northern hardwood forest". Thesis, 2021. https://hdl.handle.net/2144/42229.

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Northern hardwood forests are expected to experience an increase in mean annual air temperatures, and a decrease in winter snowpack and greater frequency of soil freeze/thaw cycles (FTCs) by the end of the century. As a result of these anticipated changes, northern hardwood forests in the northeastern U.S. will also have warmer soil temperatures in the growing season and colder soils in winter. Prior studies show that warmer soils in the growing season increase net primary productivity (NPP) and C storage as a result of increased soil net N mineralization, while increases in soil freezing in winter reduces plant uptake of N and C as a result of root damage. However, the combined effects of warmer soils in the growing season and increased soil freeze/thaw cycles in winter on tree litter mass and chemistry are unknown. We report here results from the Climate Change Across Seasons Experiment (CCASE) at Hubbard Brook Experimental Forest in New Hampshire, USA to characterize the response of leaf litter mass and chemistry to growing season warming combined with soil freeze–thaw cycles in winter. Across the years 2014-2017, litterfall mass and chemistry (%C, %N, C:N) were not significantly affected by changes in soil temperature; however, there was a trend of higher total litterfall mass and litter N mass from plots where soils were warmed in the growing season, but this increase disappeared with the addition of FTCs in winter. These results indicate that while rates of NPP and the total mass of N could be increased with rising soil temperatures over the next century in northern hardwood forests, the combination of warmer soils in the growing season and colder soils in winter may ultimate have little to no impact on litter mass or chemistry. We conclude that considering the combined effects of climate changes in the growing season and in winter is vital for the accurate determination of the response of litterfall mass and chemistry in northern hardwood forests.

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