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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Právní úprava ochrany lesa / Legal regulation of forest protection

Hargaš, Martin January 2012 (has links)
The aim of the thesis "Legal regulation of forest protection" is to summarize the main instruments of the Czech law to ensuring the protection of forests. The thesis focuses mainly on current forest legislation in the Czech Republic. The main purpose is to ascertain whether the current legislation of the protection of forests is efficient and sufficient. The thesis is divided into nine chapters. The first part of the thesis defines the forest in general, its functions and questions of its protection.
22

Dinâmica estrutural e reprodutiva da vegetação lenhosa de uma floresta paludosa em Bauru/SP / Reproductive and structural dynamic of woody vegetation in a swamp forest in Bauru/SP

Carboni, Marina 21 November 2011 (has links)
Estudos sobre a dinâmica de comunidades florestais que avaliam a interação de fatores bióticos e abióticos num determinado intervalo de tempo, expresso pelas diferenças nos valores de mortalidade, recrutamento e crescimento dos indivíduos amostrados, podem fornecer informações sobre a estrutura, mudanças temporais e espaciais, além de fornecer informações sobre a capacidade de regeneração e a ocorrência de perturbações em determinado local. No entanto, pouco se conhece sobre a dinâmica das comunidades Florestais Paludosas, apesar da crescente preocupação na preservação dessas formações ciliares para garantir a manutenção dos recursos hídricos. O presente trabalho teve por objetivo re-amostrar uma comunidade Florestal Paludosa de maneira a descrever a dinâmica temporal, de curto prazo, que pode estar afetando a composição e estrutura local. De forma complementar, estudos sobre o crescimento de plântulas, sobre a fenologia e germinação das principais espécies dessa comunidade foram realizados de maneira a contribuir para que se chegue a um primeiro modelo de dinâmica para esse tipo de floresta. A Floresta Paludosa estudada está localizada na região centro-oeste do estado de São Paulo, próximo das coordenadas 22º 20S e 49º 01W e possui 2,3 ha. Está encravada entre áreas de Floresta Estacional Semidecídua, Campo úmido e Cerradão, no município de Bauru/SP. Os resultados indicam que a estrutura e composição da floresta estudada pouco se alteraram ao longo dos cinco anos e que a dinâmica desta floresta é lenta quando comparada com outras formações vegetais. A relação da ocorrência de espécies e variáveis ambientais foi pequena indicando que as espécies estudadas que ocorrem nestas florestas estão adaptadas as condições abióticas mesmo com algumas variações. O pico de dispersão das principais espécies dessa floresta foi na estação seca e o pico de germinação foi nos primeiros dois meses após serem semeadas, independente da umidade a que estavam submetidas. A rápida germinação e o estabelecimento das plântulas antes dos meses mais chuvosos aumentam as chances de sobrevivência dessas espécies, pois a maior mortalidade entre indivíduos adultos e jovens acontece na época chuvosa. As espécies típicas de formações permanentemente encharcadas Calophyllum brasiliense, Magnolia ovata, Protium spruceanum, Dendropanax cuneatus e Xylopia emarginata, são espécies responsáveis pela formação do dossel, pela manutenção da fisionomia florestal e pela manutenção da fauna dispersora de algumas Florestas Paludosas. Essas já são características suficientes para classificá-las como estruturadores. Podemos acrescentar a esse grupo as espécies Ardisia ambigua e Geonoma brevispatha que apesar de não estarem incluídas em todas as análises realizadas aqui por serem de sub-bosque e uma palmeira com crescimento muito diferente das demais espécies, são comuns a esta formação. Já as espécies Cedrela odorata, Rapanea gardneriana, Styrax pohlii e Tapirira guianensis foram consideradas espécies complementares. Os dois grupos de espécies devem estar presentes em projetos de restauração dessas florestas. As espécies estruturadoras aparentemente tem maior potencial de reconstrução e manutenção do dossel e conseqüentemente do habitat florestal à longo prazo, dando assim condições ao estabelecimento de outras espécies e formas de vida característicos da Floresta Paludosa. / Studies about forest communities dynamics that evaluate the interaction between biotic and abiotic factors during a specific period, expressed by the differences in mortality, recruitment and growth rates of sampled individuals, may provide information about community structure, spatial and temporal changes, in addition to information about forest regeneration capacity and the occurrence of disturbance. Despite the increasing concern about the preservation of these forest formations, in order to ensure the maintenance of water resources, the dynamic of Swampy Forests communities are not well understood. This research aimed to re-sample a swampy forest community, in order to describe its short-term dynamic, which may be affecting local structure and composition. We also carried out a study of seedling growth, phenology and germination of the main species of the community, in attempt to propose a pioneer dynamic model to this type of forest formation. The studied area is located on mid-west region of São Paulo state (22º 20S e 49º 01W), and it has 2.3 ha. The remnant is surrounded by Tropical Semideciduous Forest, wet grasslands and Cerradão, in Bauru city, São Paulo. The results indicate that forest structure and composition have not suffered much alteration along five years of observations, and also that this forest dynamics can be considered slow, when compared to other forest formations. There is a weak relationship between species occurrence and environmental variables, what indicates that the species occurring in the area are adapted to abiotic conditions, even though there are variations. The highest dispersion rate of the main species occurred during the dry season, and the highest germination rate occurred during the first two months after seeding, despite the humidity the seedlings were submitted to. Seedlings fast germination and establishment before the rainy months increased their chances of surviving, because higher mortality rates among young and adult individuals occur during rainy season. Calophyllum brasiliense, Magnolia ovata, Protium spruceanum, Dendropanax cuneatus and Xylopia emarginata, which are typical species of permanently wet forest formations, are responsible for canopy structuring, forest physiognomy maintenance, and maintenance of dispersal fauna of other swampy forest remnants. These characteristics are enough to classify them as framework species. Ardisia ambigua and Geonoma brevispatha can also be included in this classification, although their different growth rates in relation to the other species studied here, because they are understorey specie and a palm, respectively. For this reason, these species were not included in all the analysis we realized. Cedrela odorata, Rapanea gardneriana, Styrax pohlii and Tapirira guianensis were considered complementary species. The two groups of species should be present in these forest restoration projects. Framework species apparently has greater potential for reconstruction and maintenance of forest canopy, and therefore the long term persistence of forest habitats, what will provide conditions for the establishment of other species and life forms characteristic of swamp forests.
23

Análise da estrutura da paisagem na bacia do Rio Corumbataí, SP. / Landscape structure analysis of the Corumbataí River Basin, SP.

Valente, Roberta de Oliveira Averna 06 December 2001 (has links)
A importância regional da Bacia do Rio Corumbataí para o abastecimento de água, em qualidade e quantidade, e o elevado nível de desmatamento que é na atualidade um dos fatores que mais afetam a sua biodiversidade, motivaram a análise da estrutura paisagem dessa área. Para essa análise foi produzido o mapa de uso e cobertura do solo da bacia e aplicados índices de ecologia da paisagem. O mapa de uso e cobertura do solo foi produzido pela classificação digital supervisionada (algoritmo de máxima verossimilhança) de imagens orbitais digitais (SPOT e LANDSAT ), com exatidão global de 91,10%.Os índices de ecologia da paisagem (calculados pelo software FRAGSTATS) foram determinados por sub-bacias (Passa-Cinco, Alto Corumbataí, Médio Corumbataí, Ribeirão Claro e Baixo Corumbataí), sendo utilizados os que fazem a caracterização em nível de fragmentos e em nível de classes de uso e cobertura do solo. Os índices referentes às classes forneceram as caracterizações das classes floresta nativa (Floresta Estacional Semidecidual) e cerrado; e os referentes a fragmentos a caracterização, dos seus respectivos remanescentes. As caracterizações quantitativas em nível de fragmentos e de classes de uso e cobertura do solo foram feitas com os grupos de índices de área; densidade, tamanho e variabilidade métrica; área nuclear; forma; proximidade; e dispersão e justaposição. Com base nesses índices, pode-se dizer que a estrutura florestal das sub-bacias do rio Passa-Cinco e Alto Corumbataí, apresentaram algumas diferenciações em relação às sub-bacias do Médio Corumbataí, do Ribeirão Claro, e do Baixo Corumbataí. Os índices indicaram que nas sub-bacias do Médio Corumbataí, do Ribeirão Claro, e Baixo Corumbataí, existe a predominância de fragmentos de floresta nativa menores que 15 ha e que seus fragmentos, independentemente do tamanho, estão mais distantes uns dos outros e, portanto, mais sujeitos às ações dos outros usos e coberturas do solo que os remanescentes das sub-bacias do Alto Corumbataí e do rio Passa-Cinco. Nas sub-bacias do rio Passa-Cinco, do Alto Corumbataí e do Ribeirão Claro, a estrutura florestal tem como outro componente a vegetação de cerrado. No Alto Corumbataí, essa vegetação representa 78,24% do total de cerrado da Bacia do Rio Corumbataí. Neste contexto, pode-se concluir que os índices de ecologia da paisagem, quando analisados em conjunto, permitiram a caracterização da estrutura florestal das sub-bacias da Bacia do Rio Corumbataí e a avaliação dessas áreas, sob o ponto de vista da preservação e da conservação florestal. Tendo por base a preservação e a conservação florestal, pode-se concluir que as sub-bacias do Passa-Cinco e Alto Corumbataí têm um padrão de estrutura florestal com predominância de fragmentos aptos à preservação. Essa condição é conseqüência do fato de possuirem fragmentos com área nuclear suficiente para manter sua estrutura interna e a estabilidade da estrutura florestal da paisagem em que estão inseridos. As sub-bacias do Ribeirão Claro, Baixo Corumbataí e, principalmente, do Médio Corumbataí, apresentam estrutura florestal com a maioria de fragmentos devendo ser conservados. Os fragmentos que possuem a área mínima necessária à autossustentabilidade não são suficientes, em número, para manter a estabilidade dessas paisagens. / Corumbataí River Basin is regionally important for public water supply. It presents a high deforestation level, which affects deeply its biodiversity. These facts have motivated the landscape structure analysis of this area, based on its land use/land cover map and landscape ecology indices. Land use/ land cover map was produced by supervised digital classification (maximum Likelihood algorithm) of satellite images (SPOT and LANDSAT), with an classification accuracy of 91.10%. Landscape ecology indices (calculated by FRAGSTATS software) were determined for each sub-basin (Passa-Cinco, Alto Corumbataí, Médio Corumbataí, Ribeirão Claro e Baixo Corumbataí), being used those that perform the characterization to the patch level and land use/land cover classes level. The classes quantified were: native forest (Seasonal Semidecidual Forest) and cerrado. The indices groups applied were: area; density, size and variability metrics; core area; shape; proximity; interspersion and juxtaposition index. Based on those indices one can assert that the forest structure of Passa-Cinco and Alto Corumbataí sub-basins showed some differences in relation to the other ones. Most of the native forest patches in the Médio Corumbataí, Ribeirão Claro e Baixo Corumbataí sub-basins are less than the native forest patches of the other two sub-basins. Other native vegetation class in the Passa-Cinco, Alto Corumbataí, and Ribeirão Claro sub-basins is the cerrado, mainly in the Alto Corumbataí (78.24% of the whole basin). The results of this research have indicated that the landscape ecology indices allowed the forest structure characterization of the Corumbataí River sub-basins and the evaluation of those areas according to the viewpoint of forest preservation and conservation. Most of the native forest patches in Passa-Cinco and Alto Corumbataí sub-basin should be preserved. This is a consequence of the fact of having core area big enough to maintain their internal structure and stability of forest structure in the landscape where they are. For the Ribeirão Claro, Baixo Corumbataí, and mainly Médio Corumbataí, most of the native forest patches should be conserved. Those patches do not have a core area able to sustain themselves.
24

Involving forest-dependent communities in climate change mitigation : Obstacles and opportunities for successful implementation of a REDD mechanism in Babati District, Tanzania

Enqvist, Johan January 2010 (has links)
<p>The aim of this thesis is to identify how forest management in Tanzania can contribute to global climate change mitigation while improving livelihoods of forest-dependent communities.</p><p>A mechanism for reducing emissions from deforestation and forest degradation (REDD) is meant to slow increases of atmospheric CO<sub>2</sub> while channelling funds to developing countries. In Tanzania, pioneering work in participatory forest management (PFM) has promoted local-level control over forest resource use. The purpose of this study is to contribute to a linkage between REDD and PFM that maximises benefits for communities, forests and global climate.</p><p>Three PFM projects with relation to REDD have been studied, primarily using semi-structured interviews with villagers, district officials, project facilitators, researchers, consultants and policy-makers. Analysis consists of comparing experiences at different levels and putting them in the theoretical context of climate change and forest conservation.</p><p>The study identifies several issues: local and central government institutions cannot ensure equitable benefit sharing; cross-sectoral co-ordination to address fundamental causes of the problems is lacking; participation of local communities is not satisfactory.</p><p>However, the process is at an early stage. Current activities will hopefully contribute to a future framework that properly addresses these and other obstacles. If this is accomplished, PFM and REDD can complement each other in a positive way.</p>
25

Conifer chemical defense : Rugulation of bark beetle colonization and pheromone emission

Zhao, Tao January 2011 (has links)
Terpenes and phenols are of importance in conifer defense against insects and pathogens. Knowledge about tree chemical defense is vital for developing practical methods to maintain healthy forests. With the aims of characterizing the defensive chemical induction in Norway spruce Picea abies and demonstrating its ecological function to spruce bark beetle Ips typographus, we measured the terpenoid and phenolic content in the bark of mature Norway spruce trees suffering windstorm, inoculated with Ceratocystis polonica, or treated with methyl jasmonate (MeJA), and investigated the colonization and pheromone emission of I. typographus. All three stressors altered the chemical profile in the bark of Norway spruce. Trees damaged by windstorm had lower proportions of (+)-3-carene and two unidentified stilbenes, and a higher taxifolin glycoside content than trees without apparent windstorm damage; C. polonica inoculation induced extremely strong quantitative terpene accumulation in the wound reaction zone, but only increased the levels of (+)-3-carene, sabinene and terpinolene in the bark near the reaction zone; MeJA treatment generally elicited quantitative terpene accumulation, but the induction differed extensively between individual trees. In addition, logs from MeJA-treated tree showed much stronger wounding response compared to control logs. The chemical profile of Norway spruce affected the colonization and pheromone emission of I. typographus. In response to fungal inoculation, terpene present in the reaction zone inhibited the colonization of I. typographus in a dose-dependent manner. Host defense elicited by MeJA treatment reduced emissions of 2-methyl-3-buten-2-ol and (S)-cis-verbenol, the two key aggregation pheromone components of I. typographus, and altered the ratio between the two components. / QC 20110503
26

Análise da estrutura da paisagem na bacia do Rio Corumbataí, SP. / Landscape structure analysis of the Corumbataí River Basin, SP.

Roberta de Oliveira Averna Valente 06 December 2001 (has links)
A importância regional da Bacia do Rio Corumbataí para o abastecimento de água, em qualidade e quantidade, e o elevado nível de desmatamento que é na atualidade um dos fatores que mais afetam a sua biodiversidade, motivaram a análise da estrutura paisagem dessa área. Para essa análise foi produzido o mapa de uso e cobertura do solo da bacia e aplicados índices de ecologia da paisagem. O mapa de uso e cobertura do solo foi produzido pela classificação digital supervisionada (algoritmo de máxima verossimilhança) de imagens orbitais digitais (SPOT e LANDSAT ), com exatidão global de 91,10%.Os índices de ecologia da paisagem (calculados pelo software FRAGSTATS) foram determinados por sub-bacias (Passa-Cinco, Alto Corumbataí, Médio Corumbataí, Ribeirão Claro e Baixo Corumbataí), sendo utilizados os que fazem a caracterização em nível de fragmentos e em nível de classes de uso e cobertura do solo. Os índices referentes às classes forneceram as caracterizações das classes floresta nativa (Floresta Estacional Semidecidual) e cerrado; e os referentes a fragmentos a caracterização, dos seus respectivos remanescentes. As caracterizações quantitativas em nível de fragmentos e de classes de uso e cobertura do solo foram feitas com os grupos de índices de área; densidade, tamanho e variabilidade métrica; área nuclear; forma; proximidade; e dispersão e justaposição. Com base nesses índices, pode-se dizer que a estrutura florestal das sub-bacias do rio Passa-Cinco e Alto Corumbataí, apresentaram algumas diferenciações em relação às sub-bacias do Médio Corumbataí, do Ribeirão Claro, e do Baixo Corumbataí. Os índices indicaram que nas sub-bacias do Médio Corumbataí, do Ribeirão Claro, e Baixo Corumbataí, existe a predominância de fragmentos de floresta nativa menores que 15 ha e que seus fragmentos, independentemente do tamanho, estão mais distantes uns dos outros e, portanto, mais sujeitos às ações dos outros usos e coberturas do solo que os remanescentes das sub-bacias do Alto Corumbataí e do rio Passa-Cinco. Nas sub-bacias do rio Passa-Cinco, do Alto Corumbataí e do Ribeirão Claro, a estrutura florestal tem como outro componente a vegetação de cerrado. No Alto Corumbataí, essa vegetação representa 78,24% do total de cerrado da Bacia do Rio Corumbataí. Neste contexto, pode-se concluir que os índices de ecologia da paisagem, quando analisados em conjunto, permitiram a caracterização da estrutura florestal das sub-bacias da Bacia do Rio Corumbataí e a avaliação dessas áreas, sob o ponto de vista da preservação e da conservação florestal. Tendo por base a preservação e a conservação florestal, pode-se concluir que as sub-bacias do Passa-Cinco e Alto Corumbataí têm um padrão de estrutura florestal com predominância de fragmentos aptos à preservação. Essa condição é conseqüência do fato de possuirem fragmentos com área nuclear suficiente para manter sua estrutura interna e a estabilidade da estrutura florestal da paisagem em que estão inseridos. As sub-bacias do Ribeirão Claro, Baixo Corumbataí e, principalmente, do Médio Corumbataí, apresentam estrutura florestal com a maioria de fragmentos devendo ser conservados. Os fragmentos que possuem a área mínima necessária à autossustentabilidade não são suficientes, em número, para manter a estabilidade dessas paisagens. / Corumbataí River Basin is regionally important for public water supply. It presents a high deforestation level, which affects deeply its biodiversity. These facts have motivated the landscape structure analysis of this area, based on its land use/land cover map and landscape ecology indices. Land use/ land cover map was produced by supervised digital classification (maximum Likelihood algorithm) of satellite images (SPOT and LANDSAT), with an classification accuracy of 91.10%. Landscape ecology indices (calculated by FRAGSTATS software) were determined for each sub-basin (Passa-Cinco, Alto Corumbataí, Médio Corumbataí, Ribeirão Claro e Baixo Corumbataí), being used those that perform the characterization to the patch level and land use/land cover classes level. The classes quantified were: native forest (Seasonal Semidecidual Forest) and cerrado. The indices groups applied were: area; density, size and variability metrics; core area; shape; proximity; interspersion and juxtaposition index. Based on those indices one can assert that the forest structure of Passa-Cinco and Alto Corumbataí sub-basins showed some differences in relation to the other ones. Most of the native forest patches in the Médio Corumbataí, Ribeirão Claro e Baixo Corumbataí sub-basins are less than the native forest patches of the other two sub-basins. Other native vegetation class in the Passa-Cinco, Alto Corumbataí, and Ribeirão Claro sub-basins is the cerrado, mainly in the Alto Corumbataí (78.24% of the whole basin). The results of this research have indicated that the landscape ecology indices allowed the forest structure characterization of the Corumbataí River sub-basins and the evaluation of those areas according to the viewpoint of forest preservation and conservation. Most of the native forest patches in Passa-Cinco and Alto Corumbataí sub-basin should be preserved. This is a consequence of the fact of having core area big enough to maintain their internal structure and stability of forest structure in the landscape where they are. For the Ribeirão Claro, Baixo Corumbataí, and mainly Médio Corumbataí, most of the native forest patches should be conserved. Those patches do not have a core area able to sustain themselves.
27

Dinâmica estrutural e reprodutiva da vegetação lenhosa de uma floresta paludosa em Bauru/SP / Reproductive and structural dynamic of woody vegetation in a swamp forest in Bauru/SP

Marina Carboni 21 November 2011 (has links)
Estudos sobre a dinâmica de comunidades florestais que avaliam a interação de fatores bióticos e abióticos num determinado intervalo de tempo, expresso pelas diferenças nos valores de mortalidade, recrutamento e crescimento dos indivíduos amostrados, podem fornecer informações sobre a estrutura, mudanças temporais e espaciais, além de fornecer informações sobre a capacidade de regeneração e a ocorrência de perturbações em determinado local. No entanto, pouco se conhece sobre a dinâmica das comunidades Florestais Paludosas, apesar da crescente preocupação na preservação dessas formações ciliares para garantir a manutenção dos recursos hídricos. O presente trabalho teve por objetivo re-amostrar uma comunidade Florestal Paludosa de maneira a descrever a dinâmica temporal, de curto prazo, que pode estar afetando a composição e estrutura local. De forma complementar, estudos sobre o crescimento de plântulas, sobre a fenologia e germinação das principais espécies dessa comunidade foram realizados de maneira a contribuir para que se chegue a um primeiro modelo de dinâmica para esse tipo de floresta. A Floresta Paludosa estudada está localizada na região centro-oeste do estado de São Paulo, próximo das coordenadas 22º 20S e 49º 01W e possui 2,3 ha. Está encravada entre áreas de Floresta Estacional Semidecídua, Campo úmido e Cerradão, no município de Bauru/SP. Os resultados indicam que a estrutura e composição da floresta estudada pouco se alteraram ao longo dos cinco anos e que a dinâmica desta floresta é lenta quando comparada com outras formações vegetais. A relação da ocorrência de espécies e variáveis ambientais foi pequena indicando que as espécies estudadas que ocorrem nestas florestas estão adaptadas as condições abióticas mesmo com algumas variações. O pico de dispersão das principais espécies dessa floresta foi na estação seca e o pico de germinação foi nos primeiros dois meses após serem semeadas, independente da umidade a que estavam submetidas. A rápida germinação e o estabelecimento das plântulas antes dos meses mais chuvosos aumentam as chances de sobrevivência dessas espécies, pois a maior mortalidade entre indivíduos adultos e jovens acontece na época chuvosa. As espécies típicas de formações permanentemente encharcadas Calophyllum brasiliense, Magnolia ovata, Protium spruceanum, Dendropanax cuneatus e Xylopia emarginata, são espécies responsáveis pela formação do dossel, pela manutenção da fisionomia florestal e pela manutenção da fauna dispersora de algumas Florestas Paludosas. Essas já são características suficientes para classificá-las como estruturadores. Podemos acrescentar a esse grupo as espécies Ardisia ambigua e Geonoma brevispatha que apesar de não estarem incluídas em todas as análises realizadas aqui por serem de sub-bosque e uma palmeira com crescimento muito diferente das demais espécies, são comuns a esta formação. Já as espécies Cedrela odorata, Rapanea gardneriana, Styrax pohlii e Tapirira guianensis foram consideradas espécies complementares. Os dois grupos de espécies devem estar presentes em projetos de restauração dessas florestas. As espécies estruturadoras aparentemente tem maior potencial de reconstrução e manutenção do dossel e conseqüentemente do habitat florestal à longo prazo, dando assim condições ao estabelecimento de outras espécies e formas de vida característicos da Floresta Paludosa. / Studies about forest communities dynamics that evaluate the interaction between biotic and abiotic factors during a specific period, expressed by the differences in mortality, recruitment and growth rates of sampled individuals, may provide information about community structure, spatial and temporal changes, in addition to information about forest regeneration capacity and the occurrence of disturbance. Despite the increasing concern about the preservation of these forest formations, in order to ensure the maintenance of water resources, the dynamic of Swampy Forests communities are not well understood. This research aimed to re-sample a swampy forest community, in order to describe its short-term dynamic, which may be affecting local structure and composition. We also carried out a study of seedling growth, phenology and germination of the main species of the community, in attempt to propose a pioneer dynamic model to this type of forest formation. The studied area is located on mid-west region of São Paulo state (22º 20S e 49º 01W), and it has 2.3 ha. The remnant is surrounded by Tropical Semideciduous Forest, wet grasslands and Cerradão, in Bauru city, São Paulo. The results indicate that forest structure and composition have not suffered much alteration along five years of observations, and also that this forest dynamics can be considered slow, when compared to other forest formations. There is a weak relationship between species occurrence and environmental variables, what indicates that the species occurring in the area are adapted to abiotic conditions, even though there are variations. The highest dispersion rate of the main species occurred during the dry season, and the highest germination rate occurred during the first two months after seeding, despite the humidity the seedlings were submitted to. Seedlings fast germination and establishment before the rainy months increased their chances of surviving, because higher mortality rates among young and adult individuals occur during rainy season. Calophyllum brasiliense, Magnolia ovata, Protium spruceanum, Dendropanax cuneatus and Xylopia emarginata, which are typical species of permanently wet forest formations, are responsible for canopy structuring, forest physiognomy maintenance, and maintenance of dispersal fauna of other swampy forest remnants. These characteristics are enough to classify them as framework species. Ardisia ambigua and Geonoma brevispatha can also be included in this classification, although their different growth rates in relation to the other species studied here, because they are understorey specie and a palm, respectively. For this reason, these species were not included in all the analysis we realized. Cedrela odorata, Rapanea gardneriana, Styrax pohlii and Tapirira guianensis were considered complementary species. The two groups of species should be present in these forest restoration projects. Framework species apparently has greater potential for reconstruction and maintenance of forest canopy, and therefore the long term persistence of forest habitats, what will provide conditions for the establishment of other species and life forms characteristic of swamp forests.
28

Brazilian land use policies and the development of ecosystem services

Freitas, Flavio L. M. January 2017 (has links)
Concerns related to global environmental changes due to land use changes have been driving international communities towards more sustainable land use systems. Brazil is a country of global strategic importance in this matter considering that it is the nation with the largest extension of preserved tropical native vegetation, recognised for its ecosystem services and high and unique biodiversity. Expansion of forestry and agriculture is taking place rapidly in Brazil, partly over degraded pastureland, but also over native vegetation. Regulating policies to govern and limit this expansion is crucial to ensure the preservation of the ecosystems services provided by native vegetation.  This thesis aims at improving the understanding of the potential impacts of prevailing public and private policies in the conservation of nature in Brazil. For this end, the Land Use Policy Assessment (LUPA) model was employed to evaluate potential pathways of implementation of the land use policies. Paper 1 evaluated the effects of current private and public command and control regulations in the protection of above-ground carbon stocks, identifying the most relevant stakeholders holding carbon stocks. The findings suggest that about 10% of carbon stocks are unprotected, where other policy instruments based on the market will be mostly required. Paper 2 performed an assessment of the mechanism for offsetting the legal deficit of native vegetation among landholders, evaluating the different offsetting implementation practices and their impacts on nature protection and socio-economic development. The results indicate that the offsetting mechanism may have little or no additional effects on protection of native vegetation and its ecosystem services because most of the offsetting is likely to take place where native vegetation is already protected by current legislations. However, it is viable to maximise environmental and socio-economic returns from the offsetting mechanism. / <p>QC 20170510</p>
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Bioinspired smell sensor to trace pheromone released by the European spruce bark beetle

Cederquist, Isac January 2020 (has links)
Forests have as a of late become increasingly plagued with bark beetle infestations as a result of climate change. The damage caused by tree killing bark beetles has within recent years seen a substantial increase. Detecting and removing infested trees at an early stage is an essential part of mitigating the spread of and the damage caused by the beetle. Today, the most common way of early detection is visual detection by forestry personnel. However, this is time consuming with highly variable results. In this thesis a novel approach to tracing the European spruce bark beetle through pheromone detection is investigated. With this approach, the antennae of the beetle were paired with an epitaxial graphene chip in order to create a bioinspired smell sensor. Tests were conducted on the sensor in order to investigate how the resistance changed over the chip as a result of the sensor being exposed to the pheromone 2-methyl-3-buten-2-ol. As a result of the tests, a corelation between exposing the sensor to pheromone and an increase of the resistance over the graphene chip was noted. However, more tests need to be conducted in order to draw any definite conclusions about the efficacy of the sensor in its current form. Additionally there are opportunities to investigate further optimization alternatives regarding the design of the sensor.
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Obec a ochrana životního prostředí z pohledu práva / Municipality and protection of the environment from the legal point of view

Brožová, Miroslava January 2013 (has links)
The thesis titled "The Municipality and Protection of the Environment from the Viewpoint of Law" is divided into six chapters. The first chapter is the introduction, which is devoted to the constitutional foundations of protection of the environment. The second chapter deals with various kinds of instruments in environmental protection. The third chapter deals with the position of a municipality in the public administration system. The fourth chapter forms the core of the work. This chapter assesses the role of municipalities in the protection of individual components of the environment and focuses on the analysing of individual component laws. The fifth and sixth chapters are devoted to the relationship of the municipalities to the territorial planning institute and an examination of the regulations issued in a municipality that functions on its own. The conclusion focuses on the summary of the relevant issues in individual areas. In terms of environmental protection, the municipality plays an essential role, particularly thanks to its position and powers that are entrusted to the municipal authorities.

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