Dissertations / Theses: 'Silviculture'

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Sheeter, Eric. "Mechanical silviculture." Thesis, Loughborough University, 1991. https://dspace.lboro.ac.uk/2134/10527.

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Problem: How to mechanise tree planting in North American logged sites? Trees are presently hand planted. Preliminary exploration identified the following collection of sub-problems. Vehicle: How to carry tools reliably and cost effectively over rough obstacle strewn ground? Results: U.S.A. - patent granted European Patent Office - patent granted Canada - patent granted The patents cover the main form and mode of operation of a simple but unconventional vehicle. Silvicultural/mechanical: How to mechanise the handling and placement of trees? Results: Two International Patents allowed. They cover a magazine/feed mechanism and a placement mechanism. They form a planting tool. One man guides the vehicle/tool system. An array of planting tools is carried. Two problems arise from the need to make guidance manageable and the planting rate fast enough. Spacing: How to cause the members of a collection of simultaneously operating tools to space themselves appropriately the spacing being driven by machine perceived cues? Choice: How to cause a tool to move to and halt over a plan table spot, tool action being driven by machine perceived cues? Results: One International Patent allowed. Spacing: A conceptual solution is described. Choice: A semi-automatic solution is described. It involves a system of tool guidance and a system of tool set-up, both light guided. Two methods for the detection of light signals in the presence of sunlight have been investigated. Choice-automatic; two solutions have been explored. One uses standard data processing, the other "parallel" processing. Here an idealised device is described which will compare for likeness two two-dimensional patterns.

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Björse, Gisela. "Near-natural forests in southern Sweden : silvicultural and palaeoecological aspects on nature-based silviculture /." Alnarp : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 2000. http://epsilon.slu.se/avh/2000/91-576-5868-4.pdf.

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Olivotto, Giuseppe Gerrard. "Finance for silviculture in British Columbia." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26510.

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Government funding for silviculture in British Columbia has expanded recently, but remains well short of the level recommended by many foresters. This thesis contains a proposal to replace government funding with investment from capital markets. It describes the funding mechanism, analyzes the implications to government, and introduces a method of distributing investment funds through a system of competitive bidding between forest management companies. In return for their participation, investors and forest companies would both receive equity in future timber production. The thesis concludes that at a cost of foregoing 50% of its future stumpage revenue, government might replace its current spending on intensive forest management with a funding level from capital markets of $500 million to $800 million per year.
Forestry, Faculty of
Graduate

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Corrêa, Augusto Ormazabal de Faria. "Percepções dos principais atores envolvidos no zoneamento ambiental na silvicultura do Rio Grande do Sul : uma perspectiva jurídico-institucional." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2009. http://hdl.handle.net/10183/17500.

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O meio ambiente e as interações humanas estão redesenhando a ética ambiental, a fim de torná-la mais clara e dotada de maior alcance. A ordem internacional ambiental vem merecendo espaços significativos dada a sua crescente importância na tutela dos ecossistemas do planeta. As políticas nacionais foram contempladas com novos elementos, como ocorreu com a Política Nacional do Meio Ambiente, que trouxe novas leis, instrumentos legais e diversas inovações para seu campo. Há alguns anos atrás, quando entrava no Estado uma nova atividade econômica, não havia arcabouço legal que desse guarida às questões ambientais e disponibilizasse instrumentos para a gestão do meio ambiente. Não existiam exigências legais, tampouco as preocupações globais que induzem os Estados e nações a assinar protocolos de intenção ou documentos de cooperação para satisfazer esses fins. Deste modo, esta pesquisa se propôs a estudar o instrumento do Zoneamento Ambiental da Atividade da Silvicultura elaborado para o Estado do Rio Grande do Sul, analisando esse instrumento sob uma ótica jurídico-institucional. Para isto, foi utilizada como metodologia a pesquisa qualitativa, dividindo-se esta em bibliográfica e documental e pesquisa de campo, através de entrevistas com representantes de alguns órgãos ambientais, órgão do Poder Público e algumas instituições privadas integrantes do setor florestal gaúcho. Os resultados encontrados demonstram que há dúvidas quanto à aplicação da legislação sobre o Zoneamento Ambiental e quanto à subordinação legal das instituições ambientais e sua atuação. Na percepção dos entrevistados há divergências técnicas quanto às diretrizes utilizadas para a implementação desse instrumento e ainda não há consenso, inclusive judicial, que atenda aos anseios das instituições do setor florestal gaúcho. No entanto, existe conciliação quanto a eventuais impactos gerados pela atividade e a necessidade de regrá-la, permitindo maior segurança para investimentos no setor. A ciência poderá trazer as respostas necessárias para esclarecer esse impasse ambiental.
The environment and the human interactions are redesigning the environmental ethics in order to make them clearer and gifted of a wider reach. The environmental international order has been getting significant spaces given its increasing importance under the custody of the planet ecosystem. The domestic politics were contemplated with new elements as took place with the Domestic Politics of Environment that has brought new laws, legal instruments and several innovations for its field. Some years ago when a new economic activity joined the Government there was no legal features that sheltered the environmental matters and made instruments available for the environment management. There were no legal demands, nor global concern that motivated Governments and nations to sign protocols of intentions or cooperation documents to attend this aims. Thus, this research suggested studying the instrument of Environmental Zoning of the Silviculture Activities elaborated for the State of Rio Grande do Sul, analyzing such instrument under the legal-institutional view. For such, a research qualitative methodology was adopted, one dividing it in bibliographical and documental and field survey, through interview with members of some environmental institutions, organ of Judicial Power and some private institutions members of the State of Rio Grande do Sul forestial sector. Results found demonstrate that there are doubts concerning application of legislation on Environmental Zoning and concerning its legal subordination of environmental institutions and its acting. Under the view of the interviewees there are technical divergences concerning policies taken for implementing this instrument and there is still no consensus, nor a legal one, that follows the needs of the State of Rio Grande do Sul forestial sector institutions. However, there is conciliation concerning eventual impacts caused by the activity and the need to rule it, allowing more safety for investing in the sector. Science will be able to bring the necessary answers to make this environmental dilemma clearer.

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Mohamad, Aminuddin Bin. "Ecology and silviculture of Calamus manan in Peninsular Malaysia." Thesis, Bangor University, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.291685.

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Mohamed, Azmy. "Silviculture and management of Gigantochloa scortechinii in peninsular Malaysia." Thesis, Bangor University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.389522.

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Melo, Raoni de [UNESP]. "Avaliação de um sistema florestal de curta rotação de Eucalyptus spp. em função da desbrota e adubação." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/138336.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A preocupação com as questões ambientais e o desenvolvimento de diversos tipos de energias alternativas estimula a participação cada vez maior de fontes renováveis de energia. A energia gerada por meio da queima da biomassa é o maior destaque dentre as fontes renováveis, sendo uma das mais exploradas atualmente. O aumento da demanda de biomassa aumentou a necessidade de gerar uma maior quantidade de material em menor tempo e em áreas cada vez mais reduzidas. O presente estudo avaliou o crescimento e a produção da biomassa aérea em plantio de Eucalyptus grandis (Clone G21), no sistema de talhadia com enfoque na produção de biomassa florestal ao fim do ciclo de dois anos. O trabalho foi realizado na Universidade Estadual Paulista (UNESP), em área experimental da Fazenda Lageado, localizada no município de Botucatu – SP. A floresta de Eucalyptus grandis foi implantada em março de 2012 no sistema florestal de curta rotação em espaçamento de 3 x 1 m e colhida com a colhedora florestal FR 9060 da New Holland. A segunda rotação foi conduzida a partir da rebrota do plantio anterior com início em de outubro de 2013. A área foi subdivida em quatro tratamentos, os quais foram dispostos em dois fatores: com a desbrota e sem a desbrota; e com a aplicação da adubação comercial e sem a aplicação de adubação. O trabalho foi desenvolvido em um experimento inteiramente casualizado e considerou-se um esquema fatorial (2 x 2) com dois fatores, desbrota e adubação, foi realizado a ANOVA e quando apresentou diferença significativa foi realizado o teste TUKEY para a comparação entre as médias. A produção de biomassa florestal seca resultou em uma média geral dentre os tratamentos de 17,34 toneladas por hectare e o fuste foi o componente arbóreo que mais produziu tanto biomassa fresca quanto biomassa seca por hectare, o qual representa cerca de 91 % de toda a biomassa produzida na área. A densidade básica da madeira também não apresentou diferença estatística quando comparado os fatores silviculturais, obtendo uma média de 369 kg m-3. A umidade apresentou-se maior no componente fuste seguido das folhas e os galhos. Para os materiais voláteis e o teor de cinzas apenas apresentaram diferença no componente fuste, que apresentou maior média de materiais voláteis e menor média de carbono fixo. As folhas apresentaram o maior poder calorífico dentre os componentes, mas representam apenas 4,1% do total de biomassa por hectare. Nenhuma prática silvicultural comparada neste trabalho, desbrota e a adubação, apresentou um resultado com diferença significativa a 5% de probabilidade para a produção de biomassa e para a produção de energia. Desse modo, pode-se afirmar que para a talhadia de sistemas florestais de curta rotação com o enfoque para a produção de biomassa e bioenergia não faz necessário realizar as adubações e nem a desbrota, sendo que estas duas operações são onerosas, tanto economicamente como no dispêndio energético, mas para que isso ocorra devem-se atentar as boas práticas silviculturais no primeiro ciclo, principalmente para o fator adubação.
The power generated by biomass burning is the biggest highlight from renewable sources, one of the most currently used. With the increasing use of biomass, the need arises to produce more biomass in less time in a smaller area. This study aims to evaluate the growth and biomass production of Eucalyptus grandis, G21 clone, the coppice system, with a focus on production of forest biomass. The study was conducted at São Paulo State University (UNESP) in the experimental area of Lageado Farm, located in Botucatu SP. The Eucalyptus grandis forest was established in March 2012 in forest system of short rotation with spacing of 3 x 1 m at 18 months of age was held the first thinning in total area, with forest harvester FR 9060 New Holland, which gathers all the tree components, stem, branches and leaves. After harvesting the area was subdivided into 4 equal parts where set 4 treatments, which are arranged on two factors: With the completion of thinning and without the use of thinning; and the application of commercial fertilizer or without the application of commercial fertilizer. The study was conducted in a completely randomized experiment and considered a factorial arrangement (2 x 2) with two factors, thinning and fertilizing. It was found that the thinning and fertilization influenced some physical properties of forest biomass. The components of biomass differed in all the treatments. Especially the leaves which had the highest average values of the gross calorific value (20.9 MJ kg-1 ), higher fixed carbon (15 %). The highest dry matter yield, 18,690 kg, was presented by the treatment without thinning and fertilization. The same treatment also showed the highest amount of energy potential, 336.06 GJ ha-1 . Fertilization worked significantly in the production of dry biomass and consequently the energy potential per area.

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Jacoboski, Lucilene Inês. "Variação na diversidade funcional e taxonômica de aves em plantios de Eucalyptus sp." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2014. http://hdl.handle.net/10183/96856.

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As alterações no uso do solo decorrentes das atividades humanas modificam as condições ambientais, o que pode levar a mudanças na estrutura de comunidades locais. A expansão da silvicultura ao redor do mundo tem causado uma crescente preocupação em termos de conservação da biodiversidade. Isto por que ela resulta em uma simplificação e homogeneização do habitat originalmente nativo. Este estudo avaliou a estrutura da assembleia de aves em áreas de silvicultura e em floresta nativa, sendo que os principais objetivos foram: 1) avaliar o possível impacto da silvicultura sobre a riqueza, abundância e composição de espécies de aves, considerando diferentes idades de plantio; 2) avaliar se as espécies de aves registradas em áreas de silvicultura representam um subconjunto daquela registrada na floresta nativa; 3) analisar as respostas da diversidade funcional e dos atributos funcionais morfológicos e comportamentais das espécies de aves. Foram amostrados plantios de eucalipto de quatro idades de cultivo assim como áreas de floresta nativa num total de 150 pontos de escuta. A riqueza, a abundância de espécies de aves e a diversidade funcional foram significativamente maiores na floresta nativa. A composição de espécies também apresentou diferença significativa entre a floresta e os plantios de diferentes idades. Entretanto apesar da diferença na composição, as espécies que ocorrem nos plantios de eucalipto representam subconjuntos daquelas encontradas na floresta nativa, com um elevado índice de aninhamento para os plantios de idade mais avançada. Os resultados deste estudo indicam a ação de um filtro ambiental imposto pela silvicultura, selecionando espécies com requerimentos de habitat e atributos similares, assim como um maior número de espécies generalistas de habitat. Pode-se inferir então que áreas de silvicultura oferecem um habitat pouco complexo para a avifauna com um nível limitado de recursos e com isso, uma perda de funções ecológicas essenciais ao ambiente, como a dispersão de sementes.
Changes in land use resulting from human activities modify the environmental conditions, which can lead to changes in the structure of local communities. The expansion of silviculture around the world has caused a growing concern for biodiversity conservation. This is because it results in a simplification and homogenization of originally native habitat. This study evaluated the structure of the assembly of birds in areas of native forest and silviculture, and the main objectives were : 1) to evaluate the possible impact of silviculture on the richness, abundance and composition of bird species, with different ages of planting and 2) assess whether the bird species recorded in areas of silviculture represent a subset that recorded in native forest, 3) analyze the responses of functional diversity and functional morphological and behavioral traits of birds species. Eucalyptus plantations four ages of cultivation as well as areas of native forest in a total of 150 point counts were sampled. The richness, abundance of bird species and functional diversity were significantly higher in the native forest. The species composition also showed a significant difference between the forest and plantations of different ages. However despite the difference in composition, species that occur in eucalyptus plantations represent subsets of those found in the native forest, with a high level of nestedness for plantations older age. The results of this study indicate the action of an environmental filter arising for silviculture, selecting species with similar habitat requirements and traits, as well as a greater number of generalist species habitat. It can be inferred then that silviculture areas offer a bit complex habitat for birdlife with a limited amount of resources and thus, a loss of ecological functions essential to the environment, such as seed dispersal.

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Kaminski, Kyle J. "Cerulean warbler initial response to silviculture treatments in southern Indiana." CardinalScholar 1.0, 2010. http://liblink.bsu.edu/uhtbin/catkey/1567415.

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The Cerulean Warbler is a small migratory that is currently considered a species of special concern. Cerulean Warbler response to two types of silvicultural treatments in southern Indiana was assessed by comparing relative abundance and territory data collected during the two years prior to tree harvest to data collected one year immediately following the harvest. ArcGIS was then used to identify spatial attributes of territories that appeared to be important to the species. Lastly, a method of sampling canopy openings by using a Global Positioning System (GPS) unit was introduced. The results suggest that Cerulean Warblers were not negatively affected by the harvest and that moderate prescribed silviculture treatments that create small canopy openings can benefit the species.
Immediate Cerulean warbler response to silviculture in southern Indiana -- Effects of silviculture on spatial characteristics of Cerulean warbler territories -- A method of sampling canopy openings associated with Cerulean warbler territories.
Department of Biology

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Sydow, Verônica Gisela. "Vegetação de sub-bosque em monocultura de Eucalyptus saligna Sm. (Myrtaceae)." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2010. http://hdl.handle.net/10183/25146.

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A modificação da paisagem e a fragmentação de habitats são consideradas ameaças à biodiversidade mundial. Áreas cobertas por vegetação primária ainda preservadas e unidades de conservação são insuficientes para garantir a conservação de espécies. Cultivos de florestas homogêneas passaram a ser considerados como possíveis habitats alternativos para espécies florestais e podem contribuir para a conservação da biodiversidade. O Brasil é o país com maior área ocupada com plantio de eucalipto e essa vem crescendo nos últimos anos. Identificar quais fatores influenciam a diversidade da biota nos plantios é importante para a conservação de espécies. O objetivo do presente estudo foi conhecer a composição florística do sub-bosque de plantios de Eucalyptus saligna Sm. e avaliar se o tipo de solo e a idade do plantio influenciam a riqueza e a composiçao da vegetação que ocupa esse ambiente. Para isso foi realizado o levantamento das espécies vegetais que ocorrem nos cultivos localizados em solo argiloso e arenoso, nos quais os indivíduos de E. saligna tinham três e sete anos. Foram avaliados como fatores ambientais características do solo, produção de serapilheira pelas árvores do plantio, abertura do dossel, uso do solo no entorno do cultivo e tamanho do plantio. No total, foram encontradas 218 espécies vegetais. As análises estatísticas foram realizadas apenas com as espécies que estavam presentes em pelo menos duas unidades amostrais. Plantios em solo argiloso apresentaram maior riqueza que no solo arenoso e houve diferença significativa na composição de espécies entre os dois tipos de solo. Grande parte dos fatores ambientais mensurados também foram diferentes entre os solos. Não foi possível verificar diferenças na riqueza, na composição de espécies e nos fatores ambientais entre os plantios de diferentes idades. O tipo de solo pode ser um fator mais limitante do que a idade da floresta plantada para determinar a riqueza e composição das espécies que compõem o sub-bosque dos plantios. Embora a riqueza de espécies no solo arenoso seja menor, esse também é importante para a conservação, porque abriga espécies adaptadas à menor disponibilidade de recursos, que não ocorrem em outros ambientes. O grande número de espécies encontrado no sub-bosque destes plantios indica que eles podem auxiliar na conservação de espécies nativas, mas esse potencial deve ser melhor investigado. São recomendados estudos de outros fatores, como a biologia de espécies importantes ecológica e econômicamente, interações entre animais e plantas e diferentes estratégias de manejo, para investigar de que forma eles afetam a biodiversidade e como eles podem ajudar a avaliar e aumentar o potencial de conservação das florestas industriais.
Landscape change and habitat fragmentaiton are recognized as threats to global biodiversity.Areas with remaining primary vegetation and protected areas are insufficient to ensure species conservation. Forest monocultures are potencial alternative habitats for native species and may contribute to the conservation of biodiversity. Brazil is the country with the largest area occupied with eucalypt plantations, this area is also growing in the last years. Identifying which factors influence the biodiversity on plantations is important to species conservation. The objective of this study was to know the understory species composition in Eucalyptus saligna Sm. plantations and to evaluate the influence of soil type and stand age on species richness and species composition. Surveys of vegetation were performed in stands on clay and sandy soils where the eucalypt trees were three and seven years old. Other soil characteristics, litter production by stand trees, canopy open and land use surrounding stands were evaluated as environmental factors. 218 plant species were found in plantations understory. The stands on clay soil were richer than those on sandy soil. Most of the environmental factors evaluated were also different among stands on different soils type. It was not possible to verify differences on species richness and species composition nor environmental factors between stand ages. Soil type could be a more limiting factor than forest age to determine species richness and species composition on plantations understory. Sandy soils are poorer in species, but they are also important to conservation, since species that happen on sandy soils are adapted to low resources availability and do not occur at other locations. The large number of native species founded in eucalypts plantation understory indicates that these plantations may assist some native species conservation. Nevertheless, further research is needed to understand the conservation potential from eucalypt plantations. It is recommended other studies to be done for a better comprehension and to increase the importance of plantation forests to conservation, mainly studies about biology of key species, interactions between animals and plants and the effect of different management options.

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Ribeiro, José Carlos Corrêa. "Discurso e construção do imaginário acerca dos areais nas políticas voltadas à arenização no Sudoeste Gaúcho." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/128035.

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A arenização e a silvicultura vêm ocupando a pauta das políticas ambientais da região sudoeste do estado do Rio Grande do Sul desde a década de setenta. São temas fortemente associados, na medida em que a arenização é apontada como o principal processo de degradação ambiental da região sudoeste do estado, enquanto a silvicultura é priorizada como solução técnica capaz de controlar esse processo e reverter os areais. Objetiva-se, no âmbito da presente tese, demonstrar que as formulações, presentes nas políticas voltadas à arenização no sudoeste gaúcho, cristalizam um ideário amplamente favorável aos interesses privados, especialmente os das empresas silvicultoras. Com efeito, esse ideário desempenha importante papel na construção do imaginário social acerca dos areais, erroneamente denominados “desertos”. Interpelados por esse discurso, técnicos e políticos da região convertem-se em mediadores locais de interesses políticos e econômicos. A validação da presente tese consistiu na análise do discurso das principais políticas públicas e privadas voltadas à arenização, e na análise perceptual dos mediadores locais. A análise dos documentos elaborados no contexto das políticas de intervenção no processo de arenização do sudoeste gaúcho, assim como dos documentos elaborados no contexto das Nações Unidas sobre a desertificação, demonstra a transversalidade (interdiscurso) que conecta as políticas desenvolvidas nesses deslocados contextos (formações discursivas). A análise perceptual dos mediadores locais (técnicos, extensionistas rurais, membros do executivo e legislativo municipal, entre outros), realizada por meio de entrevistas estruturadas e questionários, demonstra que o imaginário desses mediadores, acerca dos areais, filia-se ao ideário cristalizado pelas instituições que elaboram as políticas de intervenção nos processos de arenização e desertificação. Esse ideário materializa-se num discurso, de viés alarmista e produtivista, construído ao longo de quatro décadas, que reconhece os areais como anomalias, transformando-os em um problema para a sociedade e uma oportunidade para a iniciativa privada.
Sandization and silviculture have been on the environmental policies agenda of the southwest region of Rio Grande do Sul since the 70's. These are strongly correlated terms in that sandization is pointed out as the main problem concerning environmental destruction. On the other hand, silviculture is seen as the technical solution capable of controlling and reversing the sandization process. Our purpose, in the scope of this thesis, is to demonstrate that the linguistic formulations in policy programs dealing with sandization in Rio Grande do Sul crystallize the ideas that represent private interests, especially the ones of silviculture companies. This ideology does indeed play an important role in the construction of social consciousness about this problem. "Areais" (sand deposits) are therefore mistakenly called "deserts" in the jargon of technical staff and officials in the region. Called upon by this discourse, they act as local mediators of political and economic interests. The discourse analysis of public and private policy programs regarding sandization and the perceptual analysis of local mediators constitute the validation of this thesis. The analysis of documents produced in the intervention context of the sandization process in this region, along with documents written in the United Nations context about desertification, shows transversality (interdiscourse) connecting policy programs shaped in different backgrounds. Perceptual analysis of local mediators (technical staff, rural extensionists, members of the local legislative and executive branches, among others), performed via structured interviews, give evidence that the mediators conception of the "areais" goes along with the ideology crystallized by institutions that elaborate intervention programs against sandization and desertification processes. This concept is materialized in an alarming and production-oriented discourse built along four decades. It assumes that "areais" are anomalies and turns them into a problem for society and an opportunity for the private sector.

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Rodrigues, Philippa Maria Joan. "Economic analysis of ecologically based mixedwood silviculture at the stand level." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/mq28983.pdf.

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Snow, Roger Dustin. "THE EFFECTS OF SILVICULTURE ON THE WOOD PROPERTIES OF SOUTHERN PINE." MSSTATE, 2007. http://sun.library.msstate.edu/ETD-db/theses/available/etd-06142007-162915/.

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The ability to predict wood properties would aid in the growing of southern pine timber for specific end uses. Three wood properties, specific gravity, shrinkage, and knottiness, were chosen as the focus of this study. Silvicultural studies focusing on southern pine management were researched for any information on their impacts on wood properties. The information from silvicultural studies was then used to evaluate growth and yield models for ease of adaptation to predict wood properties. The information necessary to predict all wood properties is not currently available. Although, specific gravity has significantly more information available than the other properties and it is probably the most predictable.

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Dyson, David Samuel Loewenstein Edward F. "Influence of competition on longleaf pine seedling recruitment in selection silviculture." Auburn, Ala., 2010. http://hdl.handle.net/10415/2045.

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Wanginiak, Thayana Cristina Rebello. "Desenvolvimento inicial de guanandi (Calophyllum brasiliense Cambess., Clusiaceae) em sistema sob cobertura e a pleno sol." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/138273.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
A busca por espécies florestais nativas com potencial econômico tem sido crescente, assim como o aumento da demanda de madeiras nobres para fins comerciais. Todavia, muitas vezes pouco se sabe sobre o ciclo de desenvolvimento, tratos silviculturais e manejo adequados para cada espécie. Dentre as espécies que vêm se destacando na silvicultura de espécies nativas está o guanandi, Calophyllum brasiliense Cambess (Calophyllaceae), que apresenta características silviculturais e de qualidade de madeira favoráveis, além da produção de frutos e sementes o que incrementa a lucratividade e possuem propriedades medicinais. Embora a espécie seja capaz de se regenerar naturalmente no interior de florestas higrófilas, é cultivada usualmente em plantios puros a pleno sol, e as informações a respeito do melhor sistema de cultivo são escassas. Buscamos com este trabalho o conhecimento sobre o melhor sistema de plantio para a espécie: sombreado ou a pleno sol. A hipótese inicial da pesquisa era de que as plantas em sistema sombreado teriam melhor crescimento e maior sobrevivência do que as de pleno sol, assim como maior tolerância à seca, por este sistema se assemelhar mais às condições de seu habitat natural. O experimento foi delineado em blocos ao acaso com dois tratamentos (pleno sol e sombreado) e três repetições, com parcelas compostas por 30 plantas. Para as análises, cada planta foi considerada uma medida repetida dentro do fator bloco. As variáveis analisadas foram: sobrevivência, crescimento em altura e em diâmetro da base do colo. Foram também feitas análises fisiológicas das plantas sobreviventes em ambos os sistemas, com estimativas da condutância estomática, potencial hídrico da folha e conteúdo relativo de água. O microclima foi monitorado durante o período de estudo e foram feitas também análises de fertilidade radiação fotossinteticamente ativa (PAR) e umidade do solo. O verão de 2014 (janeiro a março) foi extremamente quente e seco, o que provocou uma alta mortalidade das plantas. Nossa hipótese não foi confirmada, uma vez que as plantas a pleno sol demonstraram melhor sobrevivência, maior crescimento e maior condutância estomática do que as sombreadas, contrariando nossa predição inicial. Embora as condições microclimáticas do sistema sombreado tenham sido mais favoráveis (menores temperaturas máximas, maior umidade relativa do ar), a umidade do solo foi maior no sistema a pleno sol. A maior mortalidade e menor crescimento no sistema sombreado podem ser atribuídos à maior competição por água com as árvores já estabelecidas no sistema sombreado, já que neste ambiente a menor umidade do solo indicaram um maior consumo de água pelas plantas já estabelecidas.
Recently there’s a growing interest in native forest species with economic potential, due to an increasing demand for hardwood timber species. However, to date there is not enough information about developmental cycles, silvicultural treatments and management required by each species. “Guanandi”, Calophyllum brasiliense Cambess (Calophyllaceae), is one of these high potential species due to its silvicultural and wood quality characteristics, besides providing fruits and seed with medicinal properties. Although the species usually regenerates naturally within hygrophyllous forests, it has usually been cultivated as pure stands under full sun. We aimed at investigating the more adequate planting system for C. brasiliense: shaded (enrichment plantings) or under full-sun conditions. Our hypothesis was the plants in shaded system would have better growth and higher survival, as well as greater drought tolerance, as this system is more similar to the species’ natural habitats. We used a randomized block design with two treatments (full-sun and under canopy cover) and three replicates, with 30 within-block repeated measures (plants per plot). The variables analyzed were survival, height and basal diameter growth; stomatal conductance and photosynthetic active radiation (PAR). The microclimate was monitored during all over the study period and soil samples were analyzed for fertility and moisture. The summer of 2014 (January-March) was extremely hot and dry, which caused high plant mortality rates. Our hypothesis was not confirmed, since plants under full-sun had better survival, higher growth and higher stomatal conductance, despite the drier and warmer microclimatic conditions. This shall be attributed to increased competition for water with the canopy trees in the shaded system, as soil moisture was higher in the full-sun plots, in spite of the hotter and drier microclimate.

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Kerr, Gary. "Factor affecting the early growth and form of Fraxinus excelsior L. in Britain." Thesis, Bangor University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369788.

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17

McClure, Adam Blake. "Estimating Heat Tolerance of Tree Buds in the Southeastern United States." Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/101841.

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Tree diameter, bark thickness and texture, litter bulk density and chemistry, and sprouting ability are a few, species-specific adaptations and properties that may be related to an individual tree stem's potential fire resistance. Based upon these features and others, trees exhibiting similar characteristics have been broadly classified as pyrophytic or pyrophobic. To our knowledge, few if any, research studies have been conducted to determine if tree buds may exhibit speciesspecific fire or heat tolerance. Understanding potential relationships between bud characteristics and fire tolerance may assist prescribed fire managers as they target control of specific undesired tree species while promoting desired tree species. Buds of six common hardwood species in the southeastern U.S. were harvested and exposed to different heat dosages using a propane gas tube burner: red maple (Acer rubrum L.), yellow-poplar (Liriodendron tulipifera L.), American beech (Fagus grandifolia Ehrh.), mockernut hickory (Carya tomentosa Lam.), scarlet oak (Quercus coccinea Münchh.), and chestnut oak (Quercus montana Willd.). These species are commonly categorized as pyrophobic (American beech, red maple, yellow-poplar) and pyrophytic (chestnut oak, mockernut hickory, scarlet oak). Using electrolyte leakage of heated and unheated buds, the mean difference in bud percent mortality between heated and unheated buds was compared by species, functional group, and differing heat dosages. The mean difference in bud percent mortality differed between the heated and unheated buds by species (p < 0.0001). Heated buds of yellow-poplar, mockernut hickory, and chestnut oak displayed similar percent mortality; however, the presumed pyrophytic species had greater heated bud percent mortality (34.0 %) than the pyrophobic species (26.8 %) (p = 0.0003). Heated bud percent mortality differed based upon differing heat dosage levels (height above the propane burner and heat exposure time) and their species-specific interactions. Fire tolerance, as assigned and assessed by features such as bark texture and thickness, may not be directly related to mid-story tree bud physical properties (i.e. length, mass, and diameter) or fire tolerance. Research including additional species, heat dosages, and different sampling times (i.e. late fall vs. late winter) would be valuable for investigating these dynamics further. Deploying a similar, field-scale experiment before and after prescribed burns would be useful to determine how tree buds may respond to different heat dosages that could be exacted during prescribed burns.
Master of Science
Prescribed fire is utilized on millions of acres per year in the southeastern United States. These burns are conducted for a variety of reasons, including: wildlife habitat establishment, restoration, and maintenance; aesthetics; hazardous fuel reduction; and the control of undesired vegetative species. Factors that may influence an individual species' response to fire include, but are not limited to: bark thickness and texture, litter bulk density and chemistry, and resprouting strategy. These traits may differ by species and by the age of a given stem. Few studies have investigated these characteristics in younger tree stems within the southeastern United States. Additionally, few research studies in any ecosystem have investigated potential species-specific tree bud responses to increased heat. Determining if undesired tree species respond differently to heating than desired tree species may provide additional information to assist prescribed fire managers in many locations where vegetation control is a management objective. As a result of this knowledge gap, a research study was designed to investigate these dynamics in the southeastern United States for six common, hardwood tree species: red maple (Acer rubrum L.), yellow-poplar (Liriodendron tulipifera L.), American beech (Fagus grandifolia Ehrh.), mockernut hickory (Carya tomentosa Lam.), scarlet oak (Quercus coccinea Münchh.), and chestnut oak (Quercus montana Willd.). The results suggested that percent bud mortality may be species-specific, but few relationships appeared to be present to relate bud physical characteristics to bud mortality. Additionally, supposed heat tolerance groups assigned to older tree stems based upon traits, such as bark thickness and texture, did not provide a valid assessment of bud mortality. Additional research is needed to understand these dynamics further, including burning under different heat dosages, evaluating additional tree species, and assessing bud mortality resulting from in-the-field prescribed fires.

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Pezda, Angelo Marcon. "Influência da silvicultura na composição e diversidade de aves florestais no bioma pampa." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2015. http://hdl.handle.net/10183/150733.

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A perda e degradação de habitats são os principais fatores que geram diminuição da biodiversidade. A silvicultura é um dos maiores agentes de distúrbio ambiental para aves. Mudanças na diversidade de espécies entre ambientes podem ser geradas por dois mecanismos: aninhamento e/ou substituição (turnover) de espécies. As comunidades animais variam em relação às mudanças na composição dos ambientes, onde a distribuição das espécies responde aos arranjos espaciais dos elementos da paisagem. Assim, os objetivos deste trabalho foram: 1) descrever a assembleia de aves em talhões de Eucalyptus sp. 2) avaliar a composição da assembleia durante o ciclo silvicultural e a relação com a composição das assembleias de aves das matas ripárias nativas, distinguindo entre aninhamento e turnover e 3) verificar a influência do tipo de uso do solo adjacente aos plantios na riqueza das assembleias de aves. O estudo foi realizado em talhões de Eucalyptus sp. em diferentes estágios de desenvolvimento e em porções de florestas ripárias no Bioma Pampa, sendo coletado informações sobre riqueza e composição das assembleias de aves, através de pontos de contagem. Para a composição de espécies, foram realizadas análises de diversidade beta, distinguindo entre aninhamento e turnover, mostrando que a maior semelhança da composição das assembleias de aves ocorreu entre os diferentes estágios do plantio do que destes com a floresta ripária, e que a semelhança da assembleia de aves dos plantios com a assembleia da floresta nativa é menor em estágios avançados de desenvolvimento. Para as variáveis do entorno, foram feitas regressões múltiplas, indicando que a presença de ambiente florestal nativo, influencia na riqueza de espécies de aves dos plantios de Eucalyptus sp., apesar de poucas espécies de interior de floresta contribuírem para composição da assembleia de aves deste ambiente antrópico.
Habitat loss and degradation are the major factors driving biodiversity loss. Silviculture is a relevant environmental disruption agent to birds. Changes in species diversity among environments can be generated by two mechanisms: nestedness and/or turnover. Animal communities vary in relation to changes of environment composition, where the species distribution respond to spatial arrangements of landscape elements. The goals of this study were: 1) describe the birds assembly in Eucalyptus sp. stands, 2) avaluate the assembly composition during the silvicultural cycle, relating to the composition of birds in the native riparian forests, distinguishing between nestedness and turnover, and 3) verify the influence of adjacent land use, on the birds assembly richness. The study took place in stands of Eucalyptus sp. in different development stages and in riparian forests portions in the Pampa Biome, and was collected information about richness and birds assembly composition by counting points. For species composition, were carried out beta diversity analyzes, distinguishing between nestedness and turnover, showing that the greatest similarity of the birds assembly composition was between the differents plantation stages than those compared to riparian forest, and the similarity of the composition of plantations birds assembly between the native forest assembly, it is smaller in Eucalyptus sp. advanced development stages. For the environmental variables, multiple regression analysis was made, indicating that the presence of surrounding native forest environments hold the richness of bird species in Eucalyptus sp. plantations, despite a few of forest interior species contribute to the man-made environmental birds assembly composition.

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Wang, Sen. "Contractual structure in British Columbia's silviculture sector, a transaction cost economic analysis." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/NQ27269.pdf.

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Hofmeyer, Philip V. "Ecology and Silviculture of Northern White-Cedar (Thuja occidentalis L.) in Maine." Fogler Library, University of Maine, 2008. http://www.library.umaine.edu/theses/pdf/HofmeyerPV2008.pdf.

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21

Redwood, Mame S. "The Effect of Silviculture Management on the Spread of Three Invasive Species." Ohio University / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1337273012.

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22

Mwang'ingo, Patrick L. P. "Ecology and silviculture of Osyris lanceolata (African Sandalwood) : an aromatic tree of Tanzania." Thesis, Bangor University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391436.

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23

Ngulube, Mzoma R. "Ecology and management of Uapaca kirkiana in southern Africa." Thesis, Bangor University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320397.

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Cordeiro, Lorenza Zanetti Silva. "Tratamento silvicultural de desbaste de liberação em uma floresta ombrófila densa no estado de Roraima." Universidade Federal de Roraima, 2012. http://www.bdtd.ufrr.br/tde_busca/arquivo.php?codArquivo=378.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Neste estudo foram avaliadas a eficiência técnica e os custos da aplicação do tratamento silvicultural de desbaste de liberação seletivo, com anelamento e aplicação de herbicida (Tordon, 50% de diluição), em uma Floresta Ombrófila Densa no Estado de Roraima, manejada de acordo com os preceitos de exploração de impac o reduzido e legislação vigente. Para analisar o efeito das características das árvores na desvitalização, foi ajustado o modelo logístico binário, indicando uma menor velocidade de desvitalização para espécies secundárias. Foram aneladas 21,6 arv/ha para favorecer a liberação de 12 arv/ha, em uma relação de 1,8 competidores para cada Árvore Comercial potencial para Colheita Futura (ACCF) liberada. O resultado da aplicação do tratamento silvicultural demonstrou uma boa efetividade da técnica, alcançando 100% de mortalidade das árvores competidoras no período de 12 meses após o anelamento, com 69% das árvores desvitalizadas dentro do período de 6 meses. O custo por hectare atingiu valor total de R$ 77,88/ha, sendo o custo por árvore anelada de R$ 3,59 e o custo por árvore liberada de R$ 5,56. Ao analisar a distribuição dos custos, observou-se que 50% deveu-se ao insumo (no caso específico a aquisição do herbicida), 47% decorreu do custo da mão de obra, 2% deveu-se à aquisição de equipamento de proteção individual e 1% de materiais. O rendimento operacional alcançou 0,76 homem/dia.ha-1, abrangendo as atividades de localização das ACCF, identificação das competidoras, corte de cipós, anelamento e aplicação de herbicida.
This study presents the results of the analysis of technical efficiency and costs of silvicultural treatments carried out in a lowland Amazon rainforest logged under reduced impact logging guidelines. The silvicultural treatments consisted in the postharvest girdling and herbicide treatment (using the product Tordon in 50% solution) of remnant trees competing with future crop trees (FCTs). In order to analyze the effect of girdling on tree mortality, a binary logistic model was utilized. The model indicated a slower mortality process for secondary tree species. On average 21,6 competing trees per hectare were girdled in order to benefit 12 FCTs per hectare (on average 1,8 competitors for every FCT). Results demonstrate the high efficiency of the silvicultural treatments tested: mortality of competitors attained 69% within six months after girdling and 100% within twelve months after girdling. The total cost of girdling amounted to BRL 77,88 per ha, BRL 3,59 per girdled tree and BRL 5,56 per FCT. Of the total cost, 50% arose from production factors, especially herbicide acquisition, while 47% were labor costs. Only 2% of the total costs were generated from work safety equipment and 1% of other materials. The operative productivity attained 0,76 man days per hectare which included the activities competitor identification, climber cutting, girdling and herbicide application.

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Brummel, Kenneth R. "The impact of group selection silviculture on timber harvesting cost in the southern Appalachians." Thesis, Virginia Tech, 1992. http://hdl.handle.net/10919/42747.

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National Forest timber management in the southern Appalachians is changing from traditional even-aged management and clearcutting to uneven-aged management and group selection silviculture. Group selection, with its small 1/2-to-2-acre patch cuts widely dispersed throughout a timber stand, has the potential to substantially increase timber harvesting costs over traditional clearcutting. This could exacerbate the below-cost timber sale issue. The objective of this study was to assess the impact of groups election silviculture on timber harvest productivity and cost in hardwood stands of the southern Appalachians. This was accomplished by collecting and analyzing field production and cost data from typical Appalachian loggers operating on group-selection timber sales. Three logging systems were chosen for the study: (1) cable yarder ,(skyline) system; (2) feller-buncher/cable skidder system; and (3) motor-manual chainsaw felling/cable skidding system. At least one full week of time-study production data was collected at each location. cost information was obtained from the cooperating loggers' records, as well as historic production and cost data from previous clearcut sales for comparison purposes. study results show that production was reduced and unit cost increased for all three logging systems when operating on group-selection timber sales as compared to clearcutting. unit cost per ton for the cable yarder system was $40.18, a 29 percent increase over their previous average clearcutting cost. The fellerbuncher/cable skidder system unit cost per ton was $14.79, a 19 percent increase over this system's average clearcutting cost. The chainsaw felling/cable skidder system cost of $16.15 per ton was 33 percent above their normal clearcutting cost. A large increase in delays and unproductive time as a result of specific group-selection timber sale characteristics appears to be the major cause of reduced logging productivity and increased costs.
Master of Science

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Rogers, Nicole. "Long-Term Dynamics And Silviculture Of Northern Hardwood Forests In The Northeast United States." ScholarWorks @ UVM, 2020. https://scholarworks.uvm.edu/graddis/1187.

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Northern hardwood forests are a vast, temperate forest-type existing across much of northeastern North America. In the northeastern U.S., these forests are found from New York to Maine where they have central cultural, ecological, and economic significance. These ecosystems are incredibly variable across this region, growing on a range of sites and influenced by a suite of biotic and abiotic conditions. Developing management regimes that accommodate the ecological complexity of these forests has been the focus of silvicultural studies for decades; however, this work has been constrained by temporal and spatial limitations. As such, there is still uncertainty regarding the evolution and variability of northern hardwood forests over time and across sites under different management scenarios. To address this uncertainty we synthesized long-term silvicultural studies (20 years +) throughout the northeast and assessed outcomes as they related to management objectives and changing forest conditions. Specifically, we explored the regeneration dynamics and development of overstory conditions for even and uneven-aged systems with four distinct approaches. First, we established context for this work through review of existing silvicultural research and analysis of the current northern hardwood resource. Next, we applied long-term, regional inventories to consider abiotic and biotic factors influencing recent sugar maple (Acer saccharum) establishment and survival. We then evaluated long-term outcomes of commonly applied even and uneven-age silvicultural systems across a range of sites in New York and New Hampshire using repeated inventories from long-term research trials. Finally, we followed the evolution of gap dynamics over eight decades in the oldest group selection study in North America; research established at the Bartlett Experimental Forest in New Hampshire in the early 1930s. Cumulatively, results showed a frequent disconnect between structure and composition of the overstory and regeneration layers, and the potential for future challenges to sustaining current overstory species. In addition, this work highlighted the pervasive, negative influence of American beech (Fagus grandifolia) across the region on regeneration of desired species, namely sugar maple and yellow birch (Betula alleghenesis). Outcomes from this work suggest that a variety of silvicultural systems can be used to maintain and regenerate northern hardwood forests; however favorable outcomes require careful consideration of site conditions with management regimes tailored accordingly.

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Cafferata, Michael J. S. "Economic Comparisons Between an Even-Aged and an Uneven-Aged Loblolly Pine Silvicultural System." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36773.

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This study compares financially optimal uneven-aged and even-aged silvicultural regimes of loblolly pine (Pinus Taeda). Uneven-aged regimes which maximize net present value (NPV) are found by quantifying the effects of diameter distribution (Q factor), maximum diameter, cutting cycle, and residual basal area on NPV. For the benchmark inputs, the regime yielding the highest NPV had a maximum diameter of 12 inches, residual basal area of 45 ft2/acre, and a cutting cycle of 11 years. Financially optimal even-aged regimes are taken from published literature of even-aged silviculture. Even-aged and uneven-aged silvicultural regimes are simulated starting from, 1) bare land, 2) a balanced uneven-aged loblolly pine stand, and 3) a mature even-aged loblolly pine stand. For the three starting conditions and selected benchmark variable values, simulation of even-aged silviculture yields NPVs of $877, $2,152 and $3,400 per acre and simulation of uneven-aged silviculture yields NPVs of $644, $2,084, and $2,569 per acre. Sensitivity analysis shows, for the levels of the variables tested, that even-aged silviculture yields higher NPVs than uneven-aged silviculture when starting from bare land or from a mature even-aged stand. When starting from an uneven-aged stand, for the variable values tested, uneven and even-aged silviculture are financially very competitive.

Aside from the aesthetic benefits of avoiding clearcutting under uneven-aged silviculture, non-timber considerations between loblolly pine silvicultural systems are not well documented. Resource professionals hold opinions often in direct conflict with each other regarding the non-timber costs and benefits of even-aged and uneven-aged silviculture when considering wildlife, soil and water, and catastrophic damage events.
Master of Science

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Gorman, Melanie Johanna. "Assessment of chemical exposure and self-reported health among tree planters in British Columbia." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/2493.

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In British Columbia harvested forests are manually replanted by seasonal workers. Fertilizers contained in perforated paper sachets are often planted with seedlings. There have been anecdotal reports of skin and respiratory illness associated with fertilizer exposure and due to potential metal content in fertilizer source material they may contain metals as contaminants. Workers may also be exposed to pesticide residues on seedlings. This study aimed to characterize fertilizer, metal and pesticide exposure among a sample of B.C. tree planters, and to examine worker respiratory and dermal health. Between May 2006 and April 2007 223 tree planters were interviewed about their respiratory and dermal health, and the exposures of 54 tree planters at five geographically-disperse worksites were monitored. Four worksites were using fertilizer and one was not. The health questionnaire was a modification of the American Thoracic Society standardized questionnaire with questions on dermal health taken from a previous UBC study. Workers were grouped in exposure categories and symptoms analysed using logistic regression. Metals were measured by ICP/MS on post shift hand wipes, full shift air sample filters, in whole blood, bulk soil, seedling root balls, and fertilizer samples. Pesticides were measured on post shift hand wipes and on bulk seedling samples. Using nursery pesticide application records, analyses focused on known pesticides applied to the seedlings at the study sites. Carbamate pesticides were analyzed by HPLC/MS and other pesticides by GC/MS. No evidence was found that tree planters who work with fertilizer are at an elevated risk of exposure to arsenic, lead, cadmium, chromium and nickel relative to other tree planters. Pesticide residues were found on seedlings taken from coastal work sites in April 2007. At coastal worksites the fungicides chlorothalonil and iprodione were found on the skin of workers at low levels (range 0.37 – 106.3 ng.cm² and 0.48 – 15.9 ng/cm² respectively). Work with fertilizer was linked with an increased risk of cough, phlegm, nasal symptoms, nose bleed, and skin irritation. Hygiene conditions at tree planting work sites are very poor. Although measured exposures were low, hygiene conditions should improve to reduce the risk of health symptoms among tree planters.

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Windelberg, Jaanice. "Skogsskötsel för att främja sociala och estetiska värden i ett friluftsområde i Trollhättans Stad." Thesis, Linnéuniversitetet, Institutionen för skog och träteknik (SOT), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-44564.

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Over 80% of Sweden's population lives in urban areas, and half of the country's forest visits will thus be in urban woodlands. Social values - how the individual experiences the forest, and the impact of the forest visits on individual health and well-being, are pointing to the importance of managing the urban woodlands. When there comes to the cultivation of the urban woodlands there are usually many opinions to consider. This study aims to investigate the various opinions on the use and forestry in an urban recreation area in the City of Trollhättan. The study addresses both general and in four cases specific suggestions on management methods. Data was obtained from both quantitative and qualitative study through survey, interviews and discussions with the users of the recreation area. Trollhättan's goal with the recreation area is to make it accessible to local residents. The users are mainly influenced by the accessibility therefore clearings and thinnings are appreciated. Clear cuts should be avoided, but can be used as a method if logging residues are removed afterward. Variation is important for the specific areas, the focus is laid on hardwood species. Where hardwood is missing the focus should be to create old and sparse forest.

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30

Ngeh, Chiambeng Paulinus. "Effects of land clearing methods on a tropical forest ecosystem and the growth of Terminalia ivorensis (A. Chev.)." Thesis, University of Edinburgh, 1989. http://hdl.handle.net/1842/15515.

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31

Fentabil, Tesfaye Teshome. "A growth and yield model for Cupressus lusitanica in Munessa Shashemene State Forest Project (MSSFP), southwest Ethiopia." Thesis, University of Aberdeen, 1996. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU602278.

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Mathematical growth and yield models were developed for the major plantation timber species, Cupressus lusitanica, growing in Munessa Shashemene State Forest Project (MSSFP), in Southwest Ethiopia, based on data from 106 temporary sample plots. Stand dominant height development was predicted by Schumacher's growth equation as a function of age and site index, defined as dominant height at reference age of 15 years. Initial diameter distributions of trees were generated using the Weibull probability density function with scale and shape parameters predicted as a function of stand parameters. Stand basal area for unthinned stands was predicted as a function of dominant height, stand age and number of stems using a modified Weibull growth equation. The basal area after thinning was simulated using a single tree diameter increment equation. The mid-diameters of each diameter class were incremented and added to the initial diameter values of each class for subsequent ages which when multiplied by class frequencies and summed gave the stand basal area. Thinnings were simulated using a power function. A compatible tree volume/taper estimation system which determined tree volume and taper was developed. The growth functions were integrated in a logical sequence, using the readily available and user friendly simple spreadsheet package, EXCEL, to produce a whole-stand distance simulation model (SIMCUP). This model also predicted final maincrop yield by size classes. Validation of the volume and diameter distribution models showed that the model (SIMUL) worked satisfactorily. Using SIMUL the effects of different levels of spacing, thinning frequency and thinning intensities on cumulative volume and sawlog volume were investigated. Experimental runs with the most frequently used thinning intensity (37.5% by stem number) at MSSFP showed that the current thinning intensity was too heavy and resulted not only in loss of cumulative volume but also merchantable volume. The cumulative volume of once, twice and three times thinned stands at the age of 25 years could be decreased by between 12.3%, 19.7% and 23% of the unthinned stand respectively. The highest merchantable sawlog volume was with no or one thinning at the age of 7 years with a rotation age of 25 years. In contrast by adopting a 25% thinning intensity the merchantable volume could be increased by between 20.4% to 10.7% relative to current yields for site index classes 27 to 12 and a stand with 1588 stems per hectare respectively. The highest merchantable sawlog volume per hectare to 15 cm top diameter was obtained at the spacing of 2.1 x 2. lm at the rotation age of 25 years The model is intended to promote silvicultural management of C. lusitanica stands in MSSFP, Southwest Ethiopia. Using SIMCUP, different levels of spacing, time of first thinning and alternative thinning intensities have been investigated and appropriate silvicultural measures suggested to achieve higher merchantable volume per hectare.

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Wichert, Marcos Cesar Passos. "Erosão hídrica e desenvolvimento inicial do Eucalyptus grandis em um Argissolo Vermelho-Amarelo submetido a diferentes métodos de preparo de solo no Vale do Paraíba - SP." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-06012006-170804/.

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No Brasil, e especialmente no estado de São Paulo na região do Vale do Paraíba, a silvicultura com o cultivo do eucalipto está se expandindo para as áreas declivosas, ocupadas com pastagens degradadas, devido ao limitado valor agropecuário destas topografias e sua maior aptidão florestal. Tais áreas estão naturalmente mais sujeitas à erosão hídrica, a qual reduz a produtividade florestal e impacta os cursos da água. Desta forma, os métodos de preparo de solo devem ser criteriosamente definidos para possibilitar o adequado crescimento inicial das florestas concomitantemente à conservação do solo. Assim, o presente trabalho teve como objetivo avaliar o efeito de diferentes métodos de preparo de solo sobre as perdas de solo e água, por erosão, e sobre o desenvolvimento inicial de plantio clonal, de E. grandis, em áreas declivosas. O ensaio foi instalado num delineamento fatorial 3x2, com três intensidades de preparo (coveamento manual, coveamento mecânico e subsolagem a favor do declive) e dois sistemas de manejo de resíduos de colheita (com e sem resíduos), com 4 repetições, num Argissolo Vermelho - Amarelo Distrófico (textura média/argilosa), com declividade média de 21%, no município de Igaratá-SP. A perda de solo e o crescimento da floresta foram avaliados durante 1 ano, entre março de 2004 e fevereiro de 2005. Em dois tratamentos, o com coveamento manual e manutenção dos resíduos (MAC) e na subsolagem sem resíduos (SUS), a erosão foi medida diretamente através do método da parcela padrão, instaladas em todas as repetições, e com dimensões de 14x24 metros. Uma parcela padrão adicional, sem preparo e sem resíduos, foi também instalada. As erosões mensuradas foram agrupadas e analisadas em três períodos (0 a 2, 3 a 7, e 8 a 12 meses). Para os demais tratamentos, a erosão foi estimada por modelos (chamados de por período e global) gerados por regressões lineares múltiplas entre a erosão observada nas parcelas padrão dos tratamentos MAC e SUS, e variáveis independentes oriundas dos atributos locais de cada parcela e das medições de 15 pinos nelas instalados. O solo e a água erodidos e coletados nas parcelas padrão foram analisados quimicamente para quantificar os macronutrientes perdidos. O crescimento inicial do eucalipto foi determinado estimando-se a cobertura do solo e a biomassa da parte aérea aos 3, 6, 9 e 12 meses. Para as parcelas padrão, houve maior erosão no tratamento SUS do que no MAC (P=0.07), com valores médios de 12,9 e 2,4 Mg ha-1 ano-1, respectivamente, e para ambos houve significativa redução da erosão com o desenvolvimento da floresta, o que não ocorreu na parcela testemunha. Os modelos preditivos de erosão só retiveram a variável dos pinos para os 2 primeiros períodos, quando as erosões foram maiores. Para o terceiro período e para o modelo global, apenas variáveis locais foram retidas: volume de solo mobilizado, cobertura do solo e teor de argila. Ambos modelos apresentaram a mesma tendência de estimar maior erosão no tratamento com subsolagem, o qual também obteve, um pequeno ganho de crescimento ao final do primeiro ano (9%). Em termos de resíduos, sua presença reduziu levemente o crescimento (9%). A maior parte da perda de nutrientes, 60%, ocorreu no solo erodido, e suplantam a entrada de nutrientes via chuva, porém são muito inferiores à exportação pela remoção dos resíduos florestais. Assim, ponderando-se os ganhos de crescimento inicial e as perdas erosivas esperadas, identifica-se para o sítio como melhor opção a manutenção dos resíduos com o uso de coveamento mecânico.
In Brazil, and especially in the state of São Paulo in the Vale do Paraíba region, eucalypt plantation is expanding to high declivity areas occupied with degraded pastures due to the limited agricultural value of these topographies and its greatest forest aptitude. Such areas are naturally more susceptible to the hydric erosion, which reduces the forest productivity and causes impacts in creeks and lakes. Therefore, the methods of soil preparation should be carefully defined to improve the initial growth of the forests together with soil conservation. Thus, this study had the objective to evaluate the effect of different methods of soil preparation on the soil and water losses by erosion, and on the initial development of E.grandis, clone, in steep areas. The experiment was installed in a 3 x 2 factorial design, with three intensities of soil preparation (manual pitting, mechanical pitting and downhill subsoiling) and two systems of residues management (with and without harvesting residues), with 4 blocks, in a Red-Yellow Argisol dystrophic (medium/clayey texture), with an average declivity of 20,3%, in Igaratá-SP. The soil loss and the growth of the forest were followed during 1 year, between March of 2004 and February of 2005. In two treatments, manual pit and maintenance of the residues (MAC) and in the subsoiling without residues (SUS), the erosion was measured directly through the method of the standart plots, installed in all the repetitions, and with 14 x 24 meters dimensions. An additional standard plot without soil preparation and residues was also installed. The erosion data was grouped and analyzed in three periods (0 to 2, 3 to 7, and 8 to 12 months). For the other treatments, the erosion was estimated using models (named per period and global) from multiple linear regressions between the erosion observed in the treatments MAC and SUS, and independent variables originated from local attributes of each plot and from the measurement of 15 pins installed inside the plots. The soil and the water eroded, collected in the standard plots were chemically analyzed to quantify the lost of macronutrients. The initial growth of the eucalypt was determined estimating soil coverage and aboveground biomass at the 3, 6, 9 and 12 months. For the standard-plots, there was larger erosion in the treatment SUS than in MAC (P=0.07), with average values of 12.9 and 2.4 Mg ha-1 year-1, respectively. For both treatments, the erosion was reduced with the growth of the forest. The erosion models only retained the variable of the pins for the first 2 periods, when erosions were larger. For the third period and for the global model, just local variables were retained: volume of prepared soil, soil coverage and clay content. Both models presented the same trend of predicting larger erosion in the treatment with subsoiling, which also obtained a small growth gain at the end of the first year (9%). For the residues, its maintenance in the area reduced the growth slightly (9%), similar to the mechanical pitty. Most of the loss of nutrients, 60%, were in the eroded soil, and this amount was larger than the rainfall inputs, but much smaller than the exportation by removing the forest residues. Thus, pondering the gains of initial growth and the expected erosion losses, the maintenance of the residues in the site together with the use of mechanical pitting can be identified as the best soil preparation option for these areas.

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33

Nanang, David M. "The silviculture, growth and yield of neem (Azadirachta indica A. Juss.) plantations in northern Ghana." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1996. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp04/MQ33419.pdf.

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34

Cunningham, Kutcher Kyle. "Linking photosynthesis physiology of upland hardwood reproduction to ecology and silviculture in the Arkansas Ozarks." Thesis, University of Arkansas at Little Rock, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=3645507.

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Oak (Quercus) forests in the Arkansas Ozarks have been important culturally, ecologically and environmentally for centuries. Historically these forests were fire dependent and dominated by oak species. In the past century, fire suppression and land management have caused these forests to densify. As a result, oaks are increasingly less abundant following disturbance in natural hardwood stands. Many applied ecological studies have explored methods and practices to maintain oak species in newly developing stands. This study attempted to link the mechanistic physiology of oak and non-oak reproduction to the applied ecological work. Varying stand conditions were generated in an undisturbed mature hardwood forest. Photosynthesis physiology was evaluated through direct and in-direct measures for six upland hardwood species in the Springfield Plateau of the Arkansas Ozarks. Environmental conditions, including sunlight canopy penetration, were significantly different based on treatment/slope position combinations. Corresponding differences in photosynthesis, development and abundance of hardwood reproduction were also significant across treatments, topographic position, and species. In conclusion, this study demonstrates that in situ measurements of photosynthetic performance are a valuable tool in predicting stand performance in oaks growing in their natural environment.

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Runesson, Anna. "Skötsel av klibbal för produktion av efterfrågad virkeskvalitet." Thesis, Linnéuniversitetet, Institutionen för skog och träteknik (SOT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-54041.

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Klibbalen (Alnus Glutinosa) växer på frisk eller fuktig mark i södra och mellersta Sverige, mestadels i bestånd mindre än ett hektar. Klibbalen är med sina kvävefixerande noduler på rötterna ett näringsberikande träd, dess kvävetillförsel medför en naturlig gödsling. Den växer som bäst på djup näringsrik, mullrik mark med rörligt grundvatten. Produktionen kan uppgå till drygt 10 m3sk/ha och år och kan föryngringsavverkas vid 35 års ålder. Virket är mjukt, har låg densitet och är lätt att bearbeta. Efter bearbetning fås en jämn fin yta som behålls även efter återfuktning. Värmeupptagningsförmågan är låg för klibbal. Däremot är virket inte intressant för tillverkning av papper då virket missfärgar pappersmassan. Undersökningen är tredelad, besök och intervjuer på lövsågverk, fältmätningar i bestånd samt analys av beståndsdata från skogsbruksplaner. Dessa tre delar ligger till grund för en syntes till en förbättrad skötselinstruktion för klibbal. Vid intervjuer med lövsågverk framkommer att de sågverk som idag sågar lövvirke upplever en brist på virke med rätt kvalitet. Med bättre skötsel och ett anpassat skötselprogram för klibbal bör det gå att få ut mer sågbart virke. God kvalitet på klibbalsvirke definieras som virke fritt från torr- och rötkvist samt brunkärna. Träden bör vid slutavverkning vara 30 till 40 cm i brösthöjd. De skogsbruksplaner som Södra Skogsägarna tillhandahöll har undersökts avseende de bestånd där klibbal är huvudträdslag. Som regel baseras skötselförslagen för dessa bestånd på andra trädslag än klibbal t.ex. gran eller björk och med ett skötselintervall på 5 år. Skötselintervallet blir ofta för långt i dessa förslag. Resultatet från såväl intervjuerna, fältmätningarna och skogsbruksplanerna har syntetiserats till ett förbättrat skötselprogram. Med en korrekt angivning av beståndsdata med anpassande skötselförslag för klibbal som har korta skötselperioder går det att skapa bättre framtida virkeskvalitet. Dagens skogsbruksplaner ger för långa tidsperioder för klibbalskötsel och bör förkortas till 2, 3 och 4-års långa perioder beroende på var i omloppstiden man befinner sig.
Common alder (Alnus Glutinosa) grows for the most part in the south and middle of Sweden, in clumps smaller than one hectare. The wood is soft, light and easy to work and maintains a smooth surface in humid environment and does not take on heath. The wood is not of interest in pulp as it discolors. The hard wood saw mills have at present a lack of good quality hardwood. With enhanced silviculture-program for common alder with shorter silviculture-interval, 2-, 3 and 4 years, and the use of a site index for common alder it should be possible to get a higher production of good quality hardwood. The current silviculture programs should be changed to shorter intervals to fit common alder silviculture. When common alder is identified for cutting, it should be taken to the hard wood industry for optimal refining.

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Colson, Christopher G. Lockaby Bruce Graeme. "Biogeochemical effects of silviculture management on intermittant streamside management zones in the coastal plain of Alabama." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SPRING/Forestry_and_Wildlife_Sciences/Thesis/Colson_Christopher_20.pdf.

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37

Heaton, Rebecca Jane. "The silviculture, nutrition and economics of short rotation willow coppice in the uplands of mid-Wales." Thesis, Cardiff University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.248239.

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38

Westfall, James A. "Simulation of Early Stand Development in Intensively Managed Loblolly Pine Plantations." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/29950.

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A system of equations was developed and incorporated into the PTAEDA2 loblolly pine stand simulator to provide growth projections from time of planting. Annual height growth is predicted using a two-parameter Weibull function, where distribution parameters are estimated from equations that utilize site index and age as predictor variables. Allometric equations are employed to estimate tree diameter and height-to-crown attributes. First year after planting mortality estimates are based on physiographic region and drainage class, with adjustments for bedding or discing site preparation treatments. Thereafter, a simple mortality function is used. The onset of competition is defined through a point density measure, which was conditioned to correspond with inflection points of basal area growth curves from observed data. Early silvicultural treatment response functions were also developed. These equations modify growth for shearing and piling, discing, and bedding site preparation methods, fertilization with phosphorous, nitrogen, and/or potassium, and 1-year or 2-year herbaceous weed control treatments. Differential responses due to drainage class and physiographic region are included in the response functions where necessary. Equations that account for interactions between certain treatments are used to adjust response levels where treatments have similar effects site conditions. Analyses of pre-competitive growth projections where no treatments are specified reveal that a small amount of over-prediction is present when compared with observed data. Predicted values in the post-competitive growth phase confirm that the addition of the pre-competitive growth system did not significantly affect the predictive behavior of the PTAEDA2 model. The simulated growth responses attributed to early silvicultural treatments are consistent with response levels reported in other studies.
Ph. D.

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Nespeca, Mathew C. "Interactive Effects of Imazapyr plus Triclopyr Ester and Imazapyr plus Glyphosate Mixtures on Woody Weed Seedlings." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/37048.

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A rapid primary herbicide screening experiment was conducted to determine if synergism or antagonism occurs with imazapyr(Arsenal®) plus triclopyr ester (Garlon 4®) and imazapyr plus glyphosate(Accord®) mixtures applied to woody weed seedlings. Using a booth sprayer, 66 herbicide treatments were applied to greenhouse grown black cherry (Prunus serotina), winged elm (Ulmus alata), sweetgum (Liquidambar styraciflua), red maple (Acer rubrum), black locust (Robinia psuedoacacia), loblolly pine (Pinus taeda), water oak (Quercus nigra) and cabbage palmetto (Sabel palmetto). The seedlings were rapidly screened and percent mortality, height and dry weight measurements were obtained five months after treatment. The sweetgum, red maple and black locust experienced unacceptable mortality in the control treatments, and were excluded from further analysis. A determination of synergistic or antagonistic interactions was made using response surface analysis, the nonlinear blending method, the isobologram method, and the Colby method. Imazapyr plus triclopyr ester mixtures were found to be synergistic on black cherry (p < 0.05), with antagonism occurring at high rates of both herbicides. Imazapyr plus triclopyr ester was additive on the remaining species. The imazapyr plus glyphosate mixtures were found to be additive for all tested species.
Master of Science

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C?rtes, Ra?ssa Tamassia. "Florestal e Agricultura Familiar: o caso da Regi?o Serrana Fluminense." Universidade Federal Rural do Rio de Janeiro, 2017. https://tede.ufrrj.br/jspui/handle/jspui/2445.

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This study seeks to present the dynamic of forestry production in family farming properties, to comprehend their practice of usual management, to apprehend the producers? interests in forestry activities, and the capacity that these activities have to provide wood for the local market. The Serrana Region of Rio de Janeiro State was chosen as study area because in it land structure predominates small rural properties, of family farming. This Region has the second major reforestation area of the State. As the topic of family forestry production has been little discussed in academic level, this essay is an exploratory research, with a collective case study. The presence or absence of forestry activities in the small properties of the region, as well as the supply and the demand of wood products in local level was obtained through secondary data. The analysis of the family producers? silvicultural system, in terms of management and production costs, availed information collected through interviews with technicians and local farmers. The study showed that the forestry production in familiar farming in the Serrana Region has potential to supply the wood local market. The forestry activities has great value to diversify the rural landscape and combating illegal logging of tropical forests. There is still a lot of resistance to these activities by farmers, given the history of eucalyptus monoculture expansion. Other species with silvicultural potential, and suitable to the small and medium farmers management, should be studied to meet the market demands. The forest element must bring a ransom and a respect to the traditional management and the way the activities are performed into each farm, in the life of each family, in the way of more sustainable activities.
O presente estudo procura apresentar a din?mica da produ??o florestal em propriedades de agricultura familiar, no sentido de compreender a pr?tica do manejo usual nessas propriedades, perceber os interesses dos produtores nas atividades florestais, e a capacidade dessas atividades para abastecer o mercado local de madeira. A Regi?o Serrana do Estado do Rio de Janeiro foi escolhida como ?rea de estudo pois sua estrutura fundi?ria se caracteriza pela predomin?ncia de pequenas propriedades rurais, de produ??o principalmente familiar. Esta regi?o se destaca por ter a segunda maior ?rea de plantios de reflorestamento do Estado, e tem como foco principal o abastecimento do mercado local. Visto que o tema da produ??o florestal familiar tem sido pouco discutido no ?mbito acad?mico, este trabalho se caracteriza como uma pesquisa explorat?ria, a partir de um estudo de caso coletivo. A presen?a ou aus?ncia da atividade florestal nas pequenas propriedades da regi?o, bem como as rela??es de oferta e demanda de produtos madeireiros a n?vel local foram obtidas de dados secund?rios. J? a an?lise do sistema silvicultural utilizado pelos produtores, em termos de manejo e custos de produ??o, foi realizada a partir das informa??es obtidas dos depoimentos de t?cnicos e produtores locais. Neste trabalho, notou-se que a produ??o florestal que ocorre em propriedades de agricultura familiar na Regi?o Serrana apresenta potencial para abastecer o mercado local de madeira. As atividades florestais t?m grande import?ncia para a diversifica??o da paisagem rural e no combate ? extra??o ilegal de madeira nativa de florestas tropicais. Ainda h? muita resist?ncia a essas atividades por parte dos agricultores, visto o hist?rico da expans?o dos monocultivos de eucalipto. Outras esp?cies com potencial silvicultural, e adequadas ao sistema de manejo existente nas pequenas e m?dias propriedades, devem ser estudadas para atender as demandas do mercado. A inser??o do elemento florestal deve trazer um resgate e um respeito ao manejo tradicional e ? forma como as atividades s?o realizadas dentro de cada propriedade, na viv?ncia de cada fam?lia, no caminho em dire??o a atividades mais sustent?veis.

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Lima, André de Mendonça. "Estrutura de habitat, diversidade e comportamento da avifauna em sistemas de silvicultura em floresta ombrófila mista." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2012. http://hdl.handle.net/10183/60552.

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A silvicultura está em franco progresso na América do Sul e as áreas de plantio têm ocupado cada vez mais territórios. No Brasil o conhecimento dos efeitos desta atividade sobre a fauna e flora nativas ainda está em formação e poucos estudos tem sido realizados na Floresta Ombrófila Mista. Os capítulos 1 e 2 discorrem sobre aspectos teóricos envolvidos na elaboração do estudo e sobre a descrição da região/área estudada, respectivamente. No capítulo 3 foi efetuado estudo sobre como o estabelecimento de espécies em plantios comerciais de Pinus elliottii e Araucaria angustifolia afetam a riqueza, densidade e composição de plantas lenhosas nativas e quais características das espécies colonizadoras são selecionadas nestes ambientes. Não houve diferença na riqueza rarefeita encontrada entre os tratamentos amostrados, contudo a densidade e a composição de espécies foram diferentes. As características de dispersão dos frutos foram diferentes entre os tratamentos e entre os plantios exóticos e nativos, com maior frequência de zoocoria ocorrendo nos plantios de P. elliottii. No capítulo 4 foi desenvolvido um estudo para verificar se a riqueza, a densidade, a composição e parâmetros de diversidade da avifauna são afetados por variáveis ambientais estruturais de plantios nativos e exóticos de diferentes idades e com e sem sub-bosque. A riqueza rarefeita, a densidade e a diversidade de aves foi mais elevada em floresta nativa e plantios com sub-bosque do que em plantios sem sub-bosque. Conforme a análise de correlação canônica houve a formação de três grupos definidos pelos parâmetros fitossociológicos: (1) plantios de P. elliotti sem sub-bosque, (2) plantios de P. elliottii com sub-bosque e (3) plantios de A. angustifolia e floresta nativa. Nos capítulos 4 e 5 existe a indicação de que a distribuição das espécies de plantas lenhosas de sub-bosque e de aves dos plantios é aninhada, onde as assembleias encontradas nos plantios são subgrupos da assembleia observada em ambiente florestal nativo. O desenvolvimento do capítulo 5 foi baseado nas táticas de forrageamento empregadas para a captura de presas por Phylloscartes ventralis nos diferentes plantios trabalhados. O comportamento de forrageio de P. ventralis foi diferente entre as áreas amostradas, onde as principais alterações foram relacionadas a manobras de ataque a presas, ao ângulo e o substrato de forrageio, a altura e a localização horizontal onde as presas foram capturadas. Na ordenação os plantios de P. elliottii com sub-bosque e A. angustifolia aparecem junto com as áreas de floresta nativa indicando que houve poucas modificações no comportamento de forrageio entre estas áreas quando comparadas a plantios de P. elliottii sem sub-bosque. A partir dos resultados obtidos foi realizado o capítulo 6 onde se reúnem todas as considerações e conclusões obtidas. Os resultados indicam que existe alteração quanto aos parâmetros de vegetação, avifauna e comportamento quando se comparam a floresta nativa e os plantios de espécies nativas e exóticas. Fica evidente a importância de utilização de espécies nativas como alternativa a espécies exóticas em áreas de silvicultura. Outra característica importante para implementação de medidas de mitigação aos impactos desta atividade econômica é a possibilidade de manutenção do sub-bosque em áreas de plantios comerciais.
Silviculture has been in sheer progress in South America and the planting areas have increasingly taken up new territories. In Brazil knowledge of the effects of this activity on native flora and fauna is still being built and few studies have been conducted in the Araucaria Forest. Chapters 1 and 2 present theoretical aspects involved in preparing the study and the description of the region / area studied, respectively. In chapter 3 a study was conducted on how the establishment of species in Pinus elliottii and Araucaria angustifolia commercial plantations affects the richness, density and composition of native woody plants and which characteristics of the colonizing species are selected in such environments. No difference in rarefied richness was found between the treatments sampled, but the density and composition of the species were different. The characteristics of fruit dispersion were different between the treatments and between exotic and native plantations, with higher incidence of zoochory in P. elliottii plantations. Chapter 4 presents the study carried out to verify whether the avifauna’s richness, density, composition and parameters of diversity are affected by structural environmental variables of native and exotic plantations of different ages and with and without understory. The rarefied richness, density and diversity of birds were higher in native forest and in plantations with understory than in plantations without understory. According to canonical correlation analysis, there was the formation of three groups defined by phytosociological parameters: (1) P. elliotti plantations without understory, (2) P. elliottii plantations with understory and (3) A. angustifolia and native forest plantations. Chapters 4 and 5 indicate that the distribution of species of understory woody plants and of plantation birds is nested, the assemblies found in plantations being subsets of the assembly observed in native forest environment. The development of chapter 5 was based on the foraging tactics employed in prey capture by Phylloscartes ventralis in the different plantations in study. The foraging behavior of P. ventralis was different in the sampled areas, the chief alterations being related to prey attack maneuvers, foraging angle and substrate, height and horizontal location where prey was captured. In ordination, P. elliottii plantations with understory and A. angustifolia rank along with the native forest areas, which indicates that there were few modifications in foraging behavior between these areas as compared to P. elliottii plantations without understory. From the results obtained chapter 6 was created, gathering all the considerations and conclusions made. The results indicate that there is alteration regarding parameters of vegetation, avifauna and behavior when comparing native forest and plantations of native and exotic species. This evidences the importance of employing native species as an alternative to exotic ones in silviculture areas. Another important feature in implementing measures for mitigating the impacts of this economic activity is the possibility of maintaining the understory in commercial plantation areas.

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Vickers, Lance Alan. "Predicting Regeneration in Appalachian Hardwood Stands Using the REGEN Expert System." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/34785.

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A study was initiated to adapt the REGEN regeneration prediction model to the Appalachians of Virginia and West Virginia. REGEN generates predictions via expert created REGEN knowledge bases (RKBs) that contain competitive rankings and stochastic parameters for selected species and size classes of advance reproduction. We developed RKBs for four site productivity classes (xeric, subxeric, submesic, mesic), and tested two (subxeric and submesic) using field collected inventory data in this study. To test the model we collected data from 48 paired sites which contained a mature stand and an adjacent regenerating stand (clearcut) of similar site productivity harvested within the past 20 years. Across all 48 sites, model predictions were within 5% of measured values on average, and explained 32% (R2 = 0.32) of the variation in species composition in regenerating stands. The species compositions of 41 of the paired stands on the Appalachian Plateau in West Virginia were further analyzed to compare species composition. Species composition was compared between the mature and regenerating stands in the subxeric and submesic site classes. A comparison of the upper canopy (dominant and codominant) species composition in regenerating stands to that of all stems â ¥ 1.5 in dbh in the mature stands was conducted as well. Our results suggest that the future species composition of stands regenerating following clearcut harvests will likely differ from previous rotations with mesophytic, shade intolerant species being more numerous. Oaks will likely assume a smaller role as the clearcuts mature, particularly on the submesic sites.
Master of Science

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Fávero, Alessandro Abreu. "ECOLOGIA E FITOSSOCIOLOGIA DA VEGETAÇÃO ARBÓREA DE UM MORRO TESTEMUNHO NO SUL DO BRASIL." Universidade Federal de Santa Maria, 2015. http://repositorio.ufsm.br/handle/1/8771.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The research evaluates the floristic, phytogeographic contingent, ecological structure descriptors, spatial phytosociology and composition of ecological guilds of trees in a testimony mountain, also examines the variables of altimetry and morphometry. It was obtained the abiotic and biotic data in 15 sample units (10 x 50m), arranged in continuous transects the top of the mountain to base, totaling 7.500m2 of sampling. Trees data were recorded with the circumference at breast height ≥ 15,7cm (1,30m above at ground level). Environmental variables were derived from altimetry (altitude, slope and level difference) and morphometry (rocky outcrop, vertical curvature, sun exposure and soil depth), besides vegetation density and gaps (canopy openness). This master s dissertation has three chapters. The first chapter characterizes the floristic and phytogeographical contingent of trees. The second chapter evaluates the biological diversity: species richness, diversity (alpha biological diversity indices) and dominance models (ranking of abundance); and examines the exploratory analysis of the relationships between species and environmental variables. The third chapter analyzes the spatial phytosociology and the composition of ecological guilds in different ecological zones in the mountain slope.
A pesquisa avalia a florística, contingente fitogeográfico, descritores de estrutura ecológica, fitossociologia espacial e composição de guildas ecológicas da vegetação arbórea em um morro testemunho, também examina as variáveis de altimetria e morfometria. Obtiveram-se os dados abióticos e bióticos em 15 unidades amostrais (10 x 50m), dispostas em transectos contínuos, do topo a base do morro, perfazendo 7.500 m2 de amostragem. Registraram-se dados de árvores com a circunferência à altura do peito ≥ 15,7cm, (1,30m de altura ao nível do solo). As variáveis ambientais foram oriundas da altimetria (altitude, declividade e diferença de nível) e morfometria (afloramento rochoso, curvatura vertical, exposição solar e profundidade do solo), além da densidade de cobertura vegetal e clareiras (abertura do dossel). A presente dissertação possui três capítulos. O primeiro capítulo caracteriza a florística e o contingente fitogeográfico da vegetação arbórea. O segundo capítulo avalia a diversidade biológica: riqueza de espécies, heterogeneidade (índices de diversidade biológica alfa) e modelos de dominância (ranking de abundância); e examina a análise exploratória das relações entre as espécies e as variáveis ambientais. O terceiro capítulo analisa a fitossociologia espacial e composição de guildas ecológicas em diferentes zonas ecológicas na vertente do morro.

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Bittencourt, Francisco Fernando Bessa. "Videografia digital aérea: proposta de um sistema e aplicação no estudo de uso do solo, cobertura vegetal e silvicultura urbana na Amazônia Central, município de Manaus, AM." Universidade Federal do Amazonas, 2010. http://tede.ufam.edu.br/handle/tede/3037.

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Made available in DSpace on 2015-04-13T12:17:49Z (GMT). No. of bitstreams: 1 Francisco Bessa (1).pdf: 5812910 bytes, checksum: 1772b9ac6e647ea7177d27ac7a88b59f (MD5) Previous issue date: 2010-12-22
FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas
Tendo em vista a necessidade de planejamento, controle e monitoramento do espaço urbano e de áreas verdes, a área de geotecnologias tem desenvolvido métodos e técnicas, bem como softwares especializados que auxiliam na realização destas atividades, buscando solucionar problemas de uso e ocupação desordenada da terra. Dentre os métodos e técnicas destaca-se a Videografia Digital Aérea Multiespectral de Alta Resolução. Admitindo-se como premissa a possibilidade do uso de imagens aéreas na identificação de uso do solo e em silvicultura urbana, objetivou-se testar esta tecnologia como uma ferramenta na identificação, classificação e quantificação da silvicultura urbana e no mapeamento de classes de uso do solo e cobertura vegetal. A área de estudo foi o município de Manaus-AM, dentro da qual foram escolhidas três áreas localizadas na zona urbana e identificadas como áreas com cobertura vegetal. O trabalho teve início com o levantamento bibliográfico, sendo desenvolvido um sistema de videografia digital aérea, iniciando-se no sobrevôo das áreas, aquisição de frames (imagens), tratamento dos frames, identificação visual das classes de cada área por meio dos frames, definição das classes de acordo com suas características visuais, as mesmas receberam atributos, cada classe foi quantificada e foram gerados mapas de cada área. O estudo resultou em um sistema que utiliza tecnologias de alta resolução de imagem, proporcionando uma qualidade comparável ou superior a de imagens obtidas de forma tradicional, com tempo e custo reduzido, permitindo avaliar as condições urbanas e a cobertura de vegetação das cidades, separando-as em classes. A pesquisa comprovou a eficiência do uso de imagens obtidas por videografia digital aérea, quando utilizadas na identificação e quantificação dos diferentes tipos de cobertura do solo em superfície urbana, sendo portanto, útil em estudos de uso e cobertura do solo. Os resultados apresentados não são conclusivos, sendo que existem observações e limitações nesta técnica. Contudo, apresentou-se uma contribuição para o estudo de uso e cobertura vegetal e silvicultura da cidade de Manaus, buscando subsidiar o manejo do ecossistema urbano.

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Loconte, Caio de Oliveira. "A sustentabilidade volumétrica do manejo florestal madeireiro." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11150/tde-17072018-183751/.

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A conservação das florestas tropicais é uma necessidade de escalas global e nacional. A Amazônia é possivelmente a maior detentora de madeira tropical do mundo, sendo o manejo florestal madeireiro uma alternativa que possibilita promover o desenvolvimento econômico e garantir a integridade dos recursos naturais. Porém, a efetividade e a continuidade dessa atividade dependem da sustentabilidade volumétrica da produção, de forma que o processo de regeneração florestal deve ser monitorado para garantir que o incremento florestal seja composto por proporção economicamente aceitável de espécies de interesse comercial. O presente trabalho avaliou as alterações do valor econômico do estoque madeireiro de florestas após 21 anos de manejo realizado por Exploração Convencional (EC) e Exploração de Impacto Reduzido (EIR), comparando-os com uma floresta sem exploração (Testemunha (TE)). Os resultados apontam que a floresta manejada via EIR recuperou 91% do volume de espécies comerciais e 94% do volume total, enquanto que os valores para EC foram, respectivamente, 72% e 85%. As explorações promoveram aumento do incremento médio anual, que foram de 0,68 m3/ha/ano em EC e 1,05 m3/ha/ano para EIR, sendo de 0,35 m3/ha/ano para TE. Porém, nos dois tipos de exploração observou-se maior dominância de espécies pioneiras, que na média aumentaram em 8% o número de indivíduos, 10% o volume e 9% a área basal. Além disso, a recuperação volumétrica ocorreu essencialmente em árvores de diâmetro <= 75 cm em EIR e <= 50 cm em EC, de forma que o diâmetro médio das árvores passíveis de corte reduziu em 8,4%. Enquanto as variáveis se mantiveram estáveis em TE, nos talhões manejados as árvores com diâmetro menor que 50 cm aumentaram a sua proporção em 13% na densidade, 29% no volume e 22% na área basal. Por outro lado, na média para os blocos, as 6% maiores árvores representam 45% do volume total, e o incremento volumétrico individual aumenta exponencialmente com o aumento do diâmetro. Esses dados permitem concluir que as técnicas de EIR são superiores ao manejo realizado via EC, mas parecem ser insuficientes para garantir a sustentabilidade volumétrica. As árvores maiores são mais importantes tanto em valor econômico quanto em incremento volumétrico, de forma que a gestão florestal orientada para a produção madeireira deve monitorar o diâmetro médio do povoamento e buscar promover o estabelecimento de estoques de elevado interesse comercial, seja através da otimização no planejando da colheita (garantindo que o estoque remanescente não seja dominado por árvores de menor porte) e pela aplicação de tratamentos silviculturais. Os tratamentos silviculturais implicam na domesticação das florestas, sendo que o desafio da silvicultura tropical é determinar qual é o limite aceitável de transformação das florestas. Até um determinado ponto, essa domesticação não é incompatível com objetivos de conservação, e a sustentabilidade da aplicação dos tratamentos deve se orientar pelo limite no qual as alterações não comprometam as funções ecológicas, a produtividade florestal e a resiliência do ecossistema.
The conservation of tropical forests is a necessity at global and national scales. The Amazon is possibly the largest stock of tropical timber in the world, and timber-based forest management is an alternative that allows to promote economic development and guarantee the integrity of natural resources. However, the effectiveness and continuity of this activity depends on the volumetric sustainability of the production, so that the process of forest regeneration must be monitored to ensure that the forest increment is composed of an economically acceptable proportion of species of commercial interest. The present study evaluated the changes in the economic value of the timber\'s stock in forests after 21 years of management by Conventional Exploration (EC) and Reduced Impact Logging (EIR), comparing them to a forest without exploration (TE). The results indicate that the forest managed by EIR recovered 91% of the volume of commercial species and 94% of the total volume, while the values for EC were, respectively, 72% and 85%. The logging operations promoted an increase of the average annual increment, which was 0.68 m3/ha/year for EC and 1.05 m3/ha/year for RIL, and just 0.35 m3/ha/year for TE. However, in both types of exploration, there was observed dominance of pioneer species, which on average increased by 8% the number of trees, 10% the volume and 9% the basal area. In addition, volumetric recovery occurred essentially in trees with diameter <= 75 cm in EIR and <= 50 cm in EC, so that the average diameter of the trees susceptible to cutting reduced by 8.4%. While the variables remained stable in TE, trees with a diameter smaller than 50 cm increased their proportion by 13% in density, 29% in volume and 22% in the basal area. On the other hand, in the average for the blocks, the 6% bigger trees represent 45% of the total volume, and the individual volumetric growth is exponentially greater with the increase of the diameter. These data allow to conclude that EIR techniques are superior to the EC\'s management, but appear to be insufficient to guarantee volumetric sustainability. Larger trees are more important in terms of both economic value and volumetric increase, so that timber-based forest management should monitor the average diameter of the stands and seek to promote the establishment of stocks of high commercial interest, either through optimization in the harvest (ensuring that the remaining stock is not dominated by smaller trees) and by the application of silvicultural treatments. Silvicultural treatments involve the domestication of forests, and the challenge of tropical forestry is to determine the acceptable limit of forest transformation. To a certain point, this domestication is not incompatible with conservation objectives, and the sustainability of the application should be guided by the limit where the changes do not compromise ecological functions, forest productivity and ecosystem resilience.

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46

MacKintosh, Hamish. "Developing the silviculture of continuous cover forestry : using the data and experience collected from the Glentress Trial Area." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/7943.

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Continuous Cover Forestry (CCF) has become increasingly popular since the early 1990s. CCF utilises several silvicultural techniques in order to promote and enhance forest structural diversity and favours natural regeneration. As CCF is relatively new to the UK there are still areas of knowledge regarding management interventions that need to be improved upon. This study utilises simple models, seedling physiology and a hybrid gap model and applies them to the Glentress Trial Area which has been under transformation from even-aged forestry since 1952. These efforts have led to an improved understanding of thinning interventions and the effects they may have on future stand structure. Since the formation of the Forestry Commission in 1919, clearfell-replant forestry has been the main form of management practiced in the UK. CCF management differs in several respects and is commonly practiced using expert knowledge in Continental Europe. In the UK the knowledge-base is still growing and therefore simple models can prove useful for guiding management. This study investigated the use of the idealised reverse-J and the Equilibrium Growing Stock (EGS). This study found that the reverse-J shaped diameter distribution is maintained at the Trial, Block and sub- Block scale indicating that an irregular structure is being approached. In addition, the diminution coefficient, a parameter of the reverse-J distribution, falls within values typical of continental Europe. Comparison of the actual diameter-frequency distribution against an ideal reverse-J distribution can inform both thinning intensity and which diameter classes to target. The EGS, which is a volume–diameter distribution, examines standing volume and how that volume is distributed across three broad diameter classes. Typical distributions from the Swiss Jura indicate that percentage volume should be split 20:30:50 across diameter classes. The EGS analysis showed that standing volume in the Trial Area is much lower than European values at just 174 m3 ha-1. In addition, the classic 20:30:50 percent split was not observed. The 1990 data set showed a 49:43:8 distribution but by 2008 it was 40:41:19. As natural regeneration is favoured in CCF a better understanding of seedling physiology is essential. This study established open (15-35 m2 ha-1) and closed canopy plots (>35 m2 ha-1). Plot characteristics were recorded and then seedlings were selected for physical measurements, chlorophyll fluorescence and gas-exchange measurements. There were clear differences between the physical characteristics with a mean Apical Dominance Ratio (APR) of 1.41 for the open plots and 0.9 for the closed plots which is consistent with previous studies suggesting an APR of 1 is needed for successful regeneration. The chlorophyll fluorescence measurements showed a linear relationship with PAR. However, although the results of the gas-exchange measurements showed an increase in photosynthetic rates with PAR for open plots, there was no obvious relationship in the closed plots. As a result, the study did not find a linear relationship between photosynthetic rate and chlorophyll fluorescence. Finally a complex, hybrid gap model was used to investigate the effects of management on predicted future stand structure. The hybrid gap model, PICUS v1.41, was parameterised for Sitka spruce. The model was used to explore different management scenarios on stand structure over two time periods; 1954-2008 and 1952- 2075. The output from the group selection with underplanting scenario, which resembled the actual management, produced realistic output that was comparable to the stand characteristics measured during the 2008 assessment. The output from the 1952-2075 runs suggested that thinning to a residual basal area suitable to allow natural regeneration (<30 m2 ha-1) or a group selection with underplanting were the best management options for maintaining structural diversity.

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Barrocas, Eva de Gouveia. "Contribution to the study of holm oak stand dynamics." Master's thesis, Universidade de Évora, 2021. http://hdl.handle.net/10174/30090.

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The holm oak is an emblematic species of the montado, a complex and biodiverse multifunctional, agro-silvopastoral system. Signs of the decline of the montado crown cover have been reported. This research followed an integrative approach to investigate how crown cover influences stand structure, natural regeneration, soil conditions, and litter layer in pure holm oak stands. Two new methodologies were created: STRUX Index that facilitates structure classification, and Natural Regeneration Classification that studies the viability of natural regeneration. The results showed that a higher crown cover was linked to uneven-aged structure, higher values of above-ground biomass, higher number of established natural regeneration, and a tendency for higher values of soil organic carbon and litter layer. Furthermore, it was observed a positive correlation between natural regeneration, litter layer, and soil organic carbon together with a negative correlation with soil pH This study brings a positive perspective on the preservation of holm oak stands; Contribuição para a dinâmica de povoamento em montado de azinho A azinheira é uma espécie emblemática do montado, sistema agro-silvopastoril, multifuncional e de elevada biodiversidade. Como a área de montado regrediu nas últimas décadas, tornou-se urgente compreender a dinâmica dos montados de azinho. Através de uma abordagem integrada, foi estudada a contribuição do grau de coberto para a dinâmica da estrutura dos povoamentos. Duas novas metodologias foram criadas: o Índice STRUX, para a classificação da estrutura do povoamento, e a Classificação de Regeneração Natural, para avaliar a viabilidade e qualidade da regeneração natural. Os resultados indicaram que valores superiores de grau de coberto estão relacionados com a estrutura irregular, com mais biomassa florestal e com mais regeneração natural instalada. Foi observada uma correlação positiva entre a regeneração natural, a manta morta e o carbono orgânico e uma correlação negativa com o pH do solo. Este estudo contribuiu para uma perspetiva positiva sobre a resiliência do montado de azinho.

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Esteves, Nuno Jorge Nunes. "Predisposition assessment modelling." Master's thesis, Faculdade de Ciências e Tecnologia, 2014. http://hdl.handle.net/10362/12194.

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Dissertation submitted for obtaining the degree of Master in Environmental Engineering
Over the last decades outbreaks of the bark beetle Ips typographus (L.) assumed a high importance in forestry due to the economic losses caused, amounting to 3 million m3 the volume of wood damaged in 2009 in Austria. In natural systems, such events result from a dynamic interaction among several factors, the integrated analysis of which can depict the predisposition level of a stand, or site, to I. typographus outbreaks. The objective of this thesis was the development of a Predisposition Model for Rosalia Forest, located in the state (Land) of Vienna in Austria. Wind and snow storms are two of the main factors that lead to a higher level of risk, as high quantities of fallen timber become available, constituting a favourable breeding habitat for I. typographus communities to proliferate. Terrain and stand related data can be translated into parameters that are registered and studied using Geographic Information Systems, in order to obtain predisposition results to wind and snow damage and ultimately overall predisposition assessments to insect infestations. Stand and site related parameters from spatial and inventory data were analysed and scored according to an Assessment System previously formulated. In order to allow for different analysis and adjustments the Model was developed in a mask-like structure. Results on predisposition for the Rosalia Forest were spatially analysed and statistically processed. It was concluded that the majority of the stand area fell in the Medium predisposition class. This was due to the diversified age structure of the stand as well as to a relatively low proportion of the host species Picea abies present in this site. The model developed not only allows for the assessment of bark beetle predisposition according to an Assessment System based on an extensive compilation of literature, but can also be used as a working tool for further sites and scenarios by entities aiming at the management of the risk of I. typographus infestations.

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Wilburn, John D. "Potential Silvicultural Effects on Bald Eagle Nesting Substrate and Economic Yields at a Navy Installation in the Chesapeake Bay: An Approach Using the Forest Vegetation Simulator and Mahalanobis Distance." Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/76946.

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In the interest of maintaining lands to fully support the military mission, Department of Defense (DOD) installations must manage competing objectives under constraints related to mission operations, regulation and compliance requirements, and budget reductions. Silviculture offers promise for ecosystem management while providing financial means through the sale of forest products. This study used forest inventory and bald eagle nest site data to investigate the potential effects of silviculture on bald eagle nesting habitat at Naval Support Facility Indian Head. Mahalanobis distance was used to define and classify preferred nesting substrate. Silviculture was simulated using the Forest Vegetation Simulator (FVS) to assess forest nesting substrate, economic yields and the tradeoffs between these two objectives. An alternative substrate model based on cumulative distribution functions (CDFs) and Boolean logic allowed evaluation of the strengths and weaknesses of the Mahalanobis distance method. The Mahalanobis distance model provided greater relative fit to the sample of nest sites compared to the CDF model but had lower discriminating power between presence and absence data. Simulation results indicate that top performing silvicultural treatments resulted in greater substrate availability compared to no-action over equal time periods. Uneven-age management was shown as the best system for providing nesting substrate as well as favorable economic yields in hardwood stands. Results also stress the importance of thinning in providing future nesting substrate and maintaining preferred substrate late in the rotation. Economic and habitat tradeoffs varied by treatment, suggesting that optimum prescriptions could be identified to provide for both objectives and minimize tradeoffs.
Master of Science

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Gautam, Krishna Hari. "Lopping regimes in community-managed sal (Shorea robusta) forests of Nepal : prospects for multiple-product silviculture for community forestry." Thesis, University of Canterbury. Forestry, 2001. http://hdl.handle.net/10092/7196.

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Forest management decisions may contribute little to sustainable forest management if those decisions do not consider the interests of different socio-economic classes and ecological actions and reactions. Recently, an immense need has arisen for forestry to have multifaceted objectives i.e., to provide multiple products with due attention to environmental effects. This study explores the potentiality of managing sal (Shorea robusta) forests for multiple products. The research looked into two aspects - experimental and ethnographic. The experimental aspect involved lopping (0, 40, 60 and 80% lopping) and litter (with or without litter) treatments. The experiments were conducted in two community-managed sal forests in western Nepal, and examined treatment effects on stem growth (tree and plot level) and the regeneration of the forests. One-event lopping up to 80% produced no adverse effects on diameter-at-breast-height (dbh), height, basal area or volume growth in two experimental forests in one year following the lopping, except the mean dbh and volume of dominant (tallest) trees and the mean volume of non-sal trees in younger and denser forest. Dominant (tallest) trees sustained up to 60% lopping but non-sal trees only 40% lopping before growth reductions. In contrast, lopping (40% and 60%) increased the growth in some instances in younger and denser forest. Litter removal produced no adverse effect on the growth. The main effects and the interaction between lopping and litter removal did not adversely affect regeneration in either forest, but increased the frequency of regeneration in most of the cases. The ethnographic study involved understanding the extent of the use of sal forests, and the indigenous knowledge of forest use and ethnosilviculture among users of three sal forests. Nine-hundred and sixty-five statements (each statement makes a piece or block of information) from 111 key informants formed the basis of information. The ethnographic study identified 637 uses and 328 blocks of ethnosilvicultural information. The relationships between indigenous knowledge status and socio-economic status (gender, age, ethnicity, income, and landholding) of respondents were analysed. Analyses showed a significant association at various levels, between types of information and socio-economic status; however, all socio-economic groups of the users held some sort of knowledge relating to forest management. Based on a one-event lopping, experimental study has shown the possibility of lopping in producing foliage and litter from sal forests without adversely affecting the growth of the tree. The importance of lopped foliage and litter has been highlighted by ethnographic study. Furthermore, ethnographic study indicated importance of several other products from sal forests for various socio-economic groups. Devaluing any product in forest management may lower the interest of particular groups within the community. Excluding any group in management decisions will lower the effectiveness of management practices. The practical importance of this research and future research needs are discussed.

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Dissertations / Theses on the topic 'Silviculture'

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