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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.
1

Effects of Microstegium vimineum (Trin.) A. Camus (Asian stiltgrass; Poaceae) on native hardwood seedling growth and survival

Jacques, Rochelle R. January 2007 (has links)
Thesis (M.S.)--Ohio University, June, 2007. / Title from PDF t.p. Includes bibliographical references.
2

Creating spatial probability distributions for longleaf pine ecosystems across east Mississippi, Alabama, the Panhandle of Florida, and west Georgia

Hogland, John Scott. MacKenzie, Mark D. January 2005 (has links) (PDF)
Thesis(M.S.)--Auburn University, 2005. / Abstract. Includes bibliographic references.
3

The response of cooper's hawks to experimental ponderosa pine forest restoration treatments in an adaptive management area /

Palladini, Michael A. January 1900 (has links)
Thesis (M.S.)--Humboldt State University, 2007. / Includes bibliographical references (leaves 39-45). Also available via Humboldt Digital Scholar.
4

The political economy of prescribed fires a land agency's decision to burn /

Berreth, Mark Alan. January 1900 (has links) (PDF)
Thesis (MS)--Montana State University--Bozeman, 2009. / Typescript. Chairperson, Graduate Committee: David E. Buschena. Includes bibliographical references (leaves 55-58).
5

ASSESSING INDICATORS OF FOREST RESTORATION SUCCESS ACROSS A CHRONOSEQUENCE OF AFFORESTED CROPLAND IN CYPRESS CREEK NATIONAL WILDLIFE REFUGE

Herrmann, Maggie C 01 May 2023 (has links) (PDF)
Since 1982, the state of Illinois has afforested over 100,000 acres of abandoned or marginal cropland. Afforestation, the planting of trees on land not in forest cover, is a sustainable forest management practice that has been shown to store carbon, increase plant diversity, improve soil and water quality, and assist in flood abatement. Our research seeks to develop practical soil and vegetative indicators that can be used by researchers and land managers alike to accurately assess changes to ecosystem function following land use shifts. To assess forest restoration success in terms of ecological function, seven ecological indicators were measured across a chronosequence of 50 afforested sites and 20 mature forested sites. Soil indicators: bulk density, aggregate stability, total nitrogen, total carbon, and labile carbon, and vegetation indicators: forest productivity and stocking density were assessed for each site. Additional sampling was completed on 25 nearby agriculture fields for each of the five soil indicators. Our data were analyzed using an analysis of variance test with multiple comparisons to examine differences among indicator values by land use category. Overall, soil indicator bulk density significantly decreased across afforested sites with stand age, whereas indicators aggregate stability, labile carbon, and total carbon significantly increased across afforested sites with stand age. Linear regression analyses were used to assess the change in indicator values with stand age. Additional linear regression analyses were used to assess the change in indicator values with site index, and significant results were recorded for 3 out of the 5 soil indicators. Indicator bulk density displayed a significant negative relationship with site index, and indicators aggregate stability and total carbon displayed a significant positive relationship with site index. Overall, our results indicated that four out of the five soil parameters measured were successful indicators of restored ecological function in afforested sites. Furthermore, we believe that the inclusion of vegetation indices forest productivity and stocking density provides vital information into forest succession and a better understanding of how productive sites benefit soil quality.
6

Establishment and growth of natural and planted conifers ten years after overstory thinning and vegetation control in 50-year-old Douglas-fir stands /

Nabel, Mark R. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 104-113). Also available on the World Wide Web.
7

Estrutura e dinâmica da comunidade de morcegos em mosaico vegetacional composto por reflorestamento de eucalipto e remanescentes de vegetação nativa no interior do estado de São Paulo /

Guimarães, Moisés. January 2019 (has links)
Orientador: Renata Cristina Batista Fonseca / Banca: Wilson Uieda / Banca: Elza Maria Guimarães Santos / Resumo: Atualmente no Brasil milhares de hectares estão sendo utilizados para o plantio de eucalipto e consequentemente essas áreas sofrem corte raso de tempos em tempos para alimentar a produção fabril. De modo geral como medida mitigatória o setor florestal conserva, em meio a monocultura, fragmentos de vegetação nativa, respeitando a legislação ambiental nacional e seguindo os preceitos das certificadoras florestais, formando extensas áreas cobertas por um mosaico vegetacional de eucalipto e vegetação nativa. O conhecimento da fauna presente nesses mosaicos e o que ocorre com ela após o corte raso de parte do plantio é de extrema importância para a conservação da biodiversidade e os morcegos são uma ótima ferramenta em estudos que abordam esse tema, visto serem a segunda maior ordem de mamíferos em número de espécies e podem representar até 50% da fauna de mamíferos em florestais tropicais. O presente estudo foi realizado na Fazenda Rio Claro, interior do estado de São Paulo, na cidade de Lençóis Paulista, em mosaico vegetacional formado por fragmentos de Floresta Estacional Semidecidual e em plantio de eucalipto, objetivando caracterizar a fauna de morcegos presente nessa paisagem e analisar o que ocorre com essa comunidade após o corte raso de parte do plantio. O trabalho de campo ocorreu entre outubro de 2007 e julho de 2010, com sessões de capturas em vegetação nativa e em plantio de eucalipto. O esforço amostral foi de 42 noites de captura utilizando 40 redes de 12 metros de ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Presently in Brazil thousands of hectares are occupied by eucalyptus plantations and those areas are completely deforested in a timely manner in order to supply the production chain. Generally as mitigation measure the forestry industry preserves native forest fragments among monoculture patches respecting the national environmental laws and the sustainable forestry certification guidelines, which creates large areas covered by a vegetation mosaic of eucalyptus and native forest. Assessing the fauna in these mosaic areas and consequences after partial harvest is extremely important for biodiversity conservation. Bats are a great tool for studying this topic since they represent the second largest mammalian order regarding number of species and up to 50% of mammalian fauna in tropical forests. The present study was developed at Fazenda Rio Claro, São Paulo state countryside, in Lençóis Paulista city, in a vegetation mosaic of Seasonal Semideciduous Forest and Eucalyptus sp plantation, and its aim was to assess bat fauna in the landscape and analyze changes within this community after partial harvest. Fieldwork was carried out between October 2007 and July 2010 with capture sessions in native vegetation and eucalyptus plantation. Sampling effort comprised 42 capture nights using 40 12m-length by 2.5m-height mist nets exposed for 12 hours each night, being 24 nets set along the subcanopy and 16 set on the canopy. After 21 capture nights part of the eucalyptus plantation areas th... (Complete abstract click electronic access below) / Mestre
8

Anfíbios anuros em áreas em processo de restauração florestal após mineração de bauxita, Poços de Caldas-MG / Anuran amphibians in forests under process of restoration after bauxite mining, Poços de Caldas-MG, Brazil

Vilela, Vívian Maria de Faria Nasser 17 May 2012 (has links)
Dentre as atividades envolvidas no processo de mudança do uso da terra, está a mineração de bauxita, cuja atividade leva à constante perda de hábitat. Uma forma de reparar a degradação antrópica à diversidade e ao funcionamento dos ecossistemas naturais é utilizar o processo de restauração ecológica. Este trabalho utilizou armadilhas-de-queda para estudar o efeito da restauração florestal após a mineração de bauxita na abundância de anuros de serapilheira. Os pontos amostrais encontram-se em um mosaico vegetacional no planalto de Poços de Caldas, MG, sendo dois locais em processo de reabilitação, cinco em processo de restauração e dois locais em remanescentes secundários de Floresta Estacional Semidecidual Montana. Foram coletados dados referentes a características da vegetação (área basal; densidade; abertura do dossel e espessura da serapilheira) e a altitude em cada ponto amostral. O Critério de Informação de Akaike corrigido (AICc) foi usado para avaliar a eficácia de nove modelos construídos a priori na predição da abundância das duas espécies coletadas que apresentaram suficiência amostral, separadamente. A abundância de Rhinella pombali foi inversamente relacionada com a densidade da vegetação e com a altitude. O modelo com a abertura do dossel influenciou positivamente a abundância de Ischnocnema juipoca. A restauração florestal possibilitou a recolonização por duas espécies de anuros - E. juipoca e R. pombali, evidenciando a importância dessa atividade na reconstrução de habitats para a biodiversidade nativa. / Bauxite mining is one of the activities involved in land-use change that leads to total habitat loss. The process of ecological restoration is a way to repair anthropic damages to biodiversity and to natural ecosystems functioning. In this work, pitfall traps with drift fences were used to verify the influence of restoration of forest areas priorly submitted to bauxite mining on the abundance of leaf litter anurans. Sample sites were located in vegetation patches on the plateau of Poços de Caldas-MG, Brazil: two in areas under rehabilitation process, five in areas under restoration process and two in secondary fragments of Montane Semideciduous Seasonal Forest. Data concerning characteristics of vegetation (basal area, density, canopy openness and litter thickness) and height were collected in each sample site. The corrected Akaike Information Criterion (AICc) was used to evaluate the efficiency of nine models constructed a priori to predict abundance of two species collected that presented sampling sufficiency, analysed as separate groups. Abundance of Rhinella pombali was inversely related to height and vegetation density. The canopy openness model positively influenced abundance of Ischnocnema juipoca. Recolonization by two anuran species E. juipoca and R. pombali was possible due to forest restoration, which shows the importance of this process in reconstructing habitats for native biodiversity.
9

Desenvolvimento de plantas de copaifera langsdorffii desf. em viveiro e na recuperação de nascentes em condições de cerrado

Carvalho, Marla Guedes Cordeiro 04 April 2018 (has links)
O bioma Cerrado sofre cada vez mais com os desmatamentos sem controle, que acabam por causar o desequilíbrio ambiental. Com isso gera a necessidade de realizar um desenvolvimento sustentável associando o social, ambiental e financeiro. Surgindo também a importância de se reestruturar paisagens que foram degradados ambientalmente aumentando a demanda por pesquisas voltadas a produção de mudas nativas. A Copaifera langsdorffii Desf. é uma espécie que tem se destacado, por ter propriedades medicinais, além de ser adaptável a diferentes fisionomias do Cerrado. Assim, a presente pesquisa tem como objetivo explanar as principais características da espécie Copaifera langsdorffii Desf. além de avaliar o desenvolvimento e a qualidade de mudas desta espécie sob níveis de sombreamento em condições de Cerrado e o monitoramento de mudas em campo em uma área de recuperação de áreas degradadas. Pode-se concluir que as mudas de Copaifera langsdorffii Desf. quando submetidas a condição de luminosidade diferenciada em viveiros possuem um melhor desenvolvimento a pleno sol, e ao serem monitoradas em condições de campo, as plantas demostraram crescimento lento, atingindo 72 cm de altura aos 3,5 anos e 50% de sobrevivência a partir de 1,4 anos. / The Cerrado biome suffers more and more with the uncontrolled deforestation that end up causing the environmental imbalance. With this, it generates the need to carry out a sustainable development involving the social, environmental and financial. Soon, the importance of restructuring landscapes that were degraded environmentally, increasing the demand for research on the production of native seedlings. The Copaifera langsdorffii Desf. is a species that has stood out because it has medicinal properties, besides being adaptable to different physiognomies of the Cerrado. Thus, the present research aims to explain the main characteristics of the species Copaifera langsdorffii Desf. in addition to evaluating the development and quality of seedlings of this species under shade levels under Cerrado conditions and the monitoring of field seedlings in a degraded area recovery area. It can be concluded that the seedlings of Copaifera langsdorffii Desf. when submitted to conditions of differentiated luminosity in nurseries have a better development in full sun, and when monitored under field conditions, plants showed slow growth, reaching 72 cm in height at 1302 days and 50% survival from 520 days . However, resistance to different landscapes concludes that this species appears as a promising alternative in the process of recovery of degraded areas
10

Banco de sementes do solo em áreas de mineração e do entorno /

Maia, Vitor Oliveira, 1988. January 2014 (has links)
Orientador: Edvaldo Aparecido Amaral da Silva / Banca: Edson Seizo Mori / Banca: João Nakagawa / Resumo: A constante pressão sofrida pelas áreas de vegetação nativa, causada pela ação antrópica, requerem estudos que visem aperfeiçoar as técnicas de conservação e a restauração ambiental. Desta forma torna-se importante o estudo do banco de sementes do solo de áreas mineradas, para possibilitar maior compreensão da composição do solo, seu potencial para a regeneração natural, sucessão ecológica e possível impacto da atividade sobre o solo. Portanto, o presente trabalho teve como objetivo conhecer a composição florística do banco de sementes do solo (na serrapilheira e a cinco cm de profundidade) de uma área minerada (região coberta por Capim Gordura) e de seu entorno (Mata Atlântica, Cerrado, Canga e populações de Eucalipto) e avaliar a contribuição em sementes do entorno na área minerada pela companhia Vale no município de Sabará, Minas Gerais, Brasil. Os pontos de coleta foram definidos através de uma Amostragem Aleatória e Sistemática (AAS), totalizando quatro pontos para cada tipo de composição vegetal. Em cada ponto de coleta foram realizadas duas repetições igualmente espaçadas a 20 metros, sempre no sentido Leste-Oeste. Em cada repetição foi coletado a serrapilheira e o solo com o uso de um gabarito vazado de 25cm x 25cm x 5cm . A serrapilheira foi coletada manualmente e o solo foi coletado após a penetração do gabarito até atingir cinco cm de profundidade. Todas as amostras coletadas foram armazenadas em sacos plásticos de 100 litros e identificadas. Após a coleta as amostras foram mantidas em salas climatizadas a 20°C e, em seguida, transferidas para vasilhas plásticas e mantidas em viveiro. No viveiro as amostras foram protegidas com telas de 50% de sombreamento. As amostras foram monitoradas diariamente e a cada quinze dias foi realizado a contagem das ... / Abstract: The constant pressure under native vegetation, caused by human activities, requires studies aimed at the improving of conservation techniques and environmental restoration. Therefore, it is important to study the soil seed bank composition in mined areas, enabling greater understanding of soil composition, its potential for natural regeneration, ecological succession and possible impacts of this activity on the ground. This study aimed to identify the floristic composition of the soil seed bank (in the litter and at five cm deep) of a mined area (area covered by fat grass) and its surroundings (Atlantic Forest, Cerrado, Canga and populations of Eucalyptus) and evaluate the contribution of the surrounding seeds in the mined area by Vale company in the city of Sabará, Minas Gerais, Brazil. The collection points were defined by a Random and Systematics Sampling (RSS), totaling four points for each type of vegetation composition. In each collection point were performed two repetitions equally spaced at 20 meters, always in the East-West direction. In each repetition was collected litter and soil using a gauging device of 25cm x 25cm x 5cm. Litter was collected manually and the soil was collected after penetration feedback up to five cm deep. All collected samples were stored in plastic bags of 100 liters and identified. After collection the samples were kept in climatized rooms at 20 ° C and then transferred to plastic pots and maintained in the nursery. In the nursery the samples were protected with 50% shading screens. Samples were monitored daily and in each 15 days was conducted the count of emerged seedlings and species identification. It is concluded that the soil seed bank (litter and soil at 5 cm deep) showed 885 emerged seedlings, distributed in 55 species and 22 families, ... / Mestre

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