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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.
41

Habitat use of bonobos at Wamba, D. R. Congo: utilization of diverse vegetation including swampy and anthropogenic habitat / コンゴ民主共和国ワンバにおけるボノボの生息地利用 : 湿地及び人為利用地を含む多様な植生の活用

Terada, Saeko 26 March 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第20962号 / 理博第4414号 / 新制||理||1634(附属図書館) / 京都大学大学院理学研究科生物科学専攻 / (主査)教授 湯本 貴和, 教授 古市 剛史, 教授 友永 雅己 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM
42

A PAIRWISE COMPARISON OF DNA SEQUENCE ALIGNMENT USING AN OPENMP IMPLEMENTATION OF THE SWAMP PARALLEL SMITH-WATERMAN ALGORITHM

Cuevas, Tristan Lee 22 April 2015 (has links)
No description available.
43

“MY GREAT TERROR, THE BLACK SWAMP”; NORTHWEST OHIO’S ENVIRONMENTAL BORDERLAND

Bogart, Dana 27 April 2015 (has links)
No description available.
44

Hydrologic Controls on Ecosystem Structure and Function in the Great Dismal Swamp

Schulte, Morgan L. 22 May 2017 (has links)
Forested peatlands of the Great Dismal Swamp (GDS) have been greatly altered since colonial times, motivating recent restoration efforts. Community structure and function were hydrologically altered by 19th and 20th century ditches installed to lower water levels and enable early timber harvesting. Contemporary forest communities are comprised of maturing remnants from selective timber harvesting that ended in the early 1970s. Red maple (Acer rubrum) has become the dominant species across GDS, encroaching on or replacing the historical mosaic of cypress (Taxodium spp.)/tupelo (Nyssa spp.), Atlantic white-cedar (Chamaecyparis thyoides), and pocosin (Pinus spp.). Moreover, peat soil has been exposed to more unsaturated conditions resulting in carbon loss through decomposition and increased peat fire frequency and severity. Installation of ditch control structures aim to control drainage and re-establish historical hydrology, vegetation communities, peat accretion rates, and fire regime. To help inform restoration and management, we conducted two complimentary studies to test hypotheses regarding hydrologic influences on vegetation, peat depths, and peat fire vulnerability. First, we found thicker peat, lower maple importance, and higher species richness at wetter sites (e.g., higher mean water levels). In our second study, we evaluated the integrated effects of peat properties and water level dynamics on peat fire vulnerability. We found decreased burn vulnerability with increased wetness, suggesting that the driest sites were always at risk to burn, whereas the wettest sites never approached fire risk conditions. Together our findings demonstrate strong hydrologic controls on GDS ecosystem structure and function, thereby informing water level management for restoration goals. / Master of Science
45

Variability and Drivers of Forest Communities at the Great Dismal Swamp

Ludwig, Raymond Francis 20 July 2018 (has links)
The Great Dismal Swamp (GDS) is a forested peatland located in the Atlantic Coastal Plain. Once a mosaic of wetland communities, disturbances (e.g., timber harvesting and ditching) have resulted in altered hydrologic regime, homogenized forest communities, and increased peat subsidence. In response, hydrologic restoration and forest management aim to enhance community composition and function. To help inform these efforts, we investigated variability and drivers of forest communities by surveying vegetation composition and structure, hydrologic indicators, and soil properties at 79 monitoring plots across GDS. Data were augmented with modeled water levels and peat depths. Our results demonstrate red maple (Acer rubrum) dominance across GDS, which decreases tree density, richness, and diversity. However, hierarchical cluster analysis identified four community types: Gum (G), Maple-Gum (M-G), Sweetgum-Maple (SG-M), and Maple (M). These communities differed in tree composition and structure; differences in other growth forms (shrubs, herbaceous, and regeneration) were limited. Modeled water levels failed to explain vegetation differences, but community associations with soil properties suggest that communities exist along a hydrologic gradient. Specifically, the G community likely exists on wetter sites whereas SG-M communities occur at drier locations. Maple-dominated communities (M and M-G; 78% of plots) likely occur across broader hydrologic gradients, explaining their dominance. However, more characterization of hydrology (i.e., time-varying water levels and soil moisture) and other drivers (e.g., site history and soil hydraulics) is needed to further explain community variation. As such, we propose future strategies for long-term monitoring to inform ongoing hydrologic restoration and forest management efforts. / Master of Science
46

Fatores abióticos definidores da distribuição dos diferentes tipos florestais (floresta paludícula, floresta estacional semidecídua ribeirinha e cerradão), nos municípios de Batatais e Restinga, SP / Abiotic factors determining the distribution of different types of forests (swamp forest, semi-deciduous riverine forest and forested savanna) in the cities of Batatais and Restinga, northeast of São Paulo State, in Brazil.

Korman, Vânia 13 October 2008 (has links)
Com o objetivo de compreender quais fatores abióticos determinam a ocorrência das diferentes formações florestais na região de Batatais, entre as coordenadas 20038S e 20058S e 47037W e 47028W, foram escolhidas três propriedades agrícolas (Fazenda Monte Belo, em Restinga, SP e Fazenda Magnólia e Sítio Pratinha, em Batatais, SP), que apresentavam remanescentes florestais representativos da região (floresta ribeirinha paludícula, floresta estacional semidecídua ribeirinha e cerradão). Para descrever a composição florística e a estrutura da comunidade arbórea foram amostradas 05 parcelas de 10 x 10 m ao redor de cada estação tensiométrica. Para o estudo dos fatores abióticos foram determinados os parâmetros físicos e químicos dos solos e as curvas de retenção de água nos solos e piezometria. A discriminação das variáveis abióticas e de vegetação foi feita através da análise de componentes principais (PCA) e, na correlação entre a abundância de espécies e fatores abióticos, foram feitas análises diretas de gradiente por meio de Análise de Correlação Canônica (CCA). A textura dos solos (teores de argila, silte e areia) e a posição no terreno (cota), foram as variáveis ambientais mais importantes na distribuição das espécies e nas variações das fisionomias florestais, com influência na retenção hídrica e nos índices de fertilidade dos solos. Essas diferenças nos teores de argila em profundidade ao longo do declive, com influência direta na retenção de umidade dos solos ou mesmo na formação de ambientes paludículos, determinaram grupos distintos de espécies e fisionomias florestais: (i) um grupo de espécies de ocorrência típica nas fisionomias de Cerrado e fortemente associado às cotas mais elevadas (solos menos férteis, bem drenados e porcentagens mais baixas de argila e silte nas camadas mais profundas), entre as quais: Matayba juglandifolia, Trichilia pallida, Lithraea molleoides, Anadenanthera falcata, Myrcia tomentosa, Copaifera langsdorffii, Erytrhoxylum pelleteranum, Platipodium elegans, Chrysophyllum marginatum, Luehea divaricata, entre outras e (ii) um grupo com espécies indicadoras de Florestas Paludículas ou de ocorrência comum nestas fisionomias, associado aos solos das cotas mais baixas (Gleissolos), com porcentagens altas de argila e silte nas camadas superficiais, mais férteis e maior retenção hídrica: Cecropia pachystachya, Citronella gongonha, Rapanea guianensis, Talauma ovata e Tapirira guianensis. Pode-se considerar um terceiro grupo de transição entre Floresta Estacional Semidecídua e Cerradão, nas cotas intermediárias e menos úmidas (espécies amostradas em parcelas localizadas nas bordas das Florestas Paludículas), onde ocorreram espécies tanto de ambiente de Cerradão, como de Floresta Estacional Semidecídua, e algumas poucas de ambiente paludículo. As porcentagens mais elevadas de Areia nos solos do Sítio Pratinha, com influência na menor retenção hídrica e também nos índices de fertilidade (solos álicos, com maior acidez e os menos férteis), podem explicar algumas diferenças na composição e abundância das espécies entre fisionomias florestais iguais. O Cerradão da Fazenda Monte Belo, mostrou-se diferente floristicamente do Cerradão do Sítio Pratinha. Esta mesma diferença ocorreu em relação às Florestas Paludículas da Fazenda Magnólia e a do Sítio Pratinha. As poucasespécies de ocorrência comum tiveram populações diferentes. A CCA evidenciou também correlações de algumas espécies com determinadas variáveis de solo. / In order to understand what abiotic factors determine the occurrence of different forest formations in the region of Batatais, coordinated between 20038\'S and 20058\'S and 47037\'W and 47028\'W, three agricultural properties were chosen (Monte Belo, in the city of Restinga, SP and Magnolia and Pratinha in Batatais, SP, Brazil), which had forests representative of the region (swamp forest, semi-deciduous riverine forest and forested savanna). To describe the floristic composition and structure of the arboreal community, 05 plots of 10 x 10 meters around each tensiometric station were sampled. For the study of abiotic factors, the physico-chemical characteristics of the soils, the soil-water-retention curves and the groundwater fluctuation were determined. The discrimination of the environmental variables and arboreal species were made through the Principal Components Analysis (PCA), and in the correlation between the abundance of species and abiotic factors, direct analyses of gradient through Canonical Correspondence Analysis (CCA) were made. The texture of the soil (levels of clay, silt and sand) and the position on the ground (altitude) were the most important environmental variables in the distribution of species and variations of forest physiognomies, with influence in the retention rates of water and soil fertility. These differences in levels of clay in depth along the slope, with direct influence on the retention of soil moisture and even in the development of swampy environment, determined distinct groups of species and forest physiognomies: (i) a group of species of typical occurrence in physiognomies of Forested Savanna and strongly associated with higher altitude (less fertile, well-drained soil and lower percentages of clay and silt in the deeper layers), including: Matayba juglandifolia, Trichilia pallida, Lithraea molleoides, Anadenanthera falcata, Myrcia tomentosa, Copaifera langsdorffii, Erytrhoxylum pelleteranum, Platipodium elegans, Chrysophyllum marginatum, Luehea divaricata, among others, and (ii) a group with indicator species of Swamp Forests or common occurrence in these physiognomies, associated with lower altitude (Gleisoil), with high percentages of clay and silt in the upper and more fertile layers, and greater water retention: Cecropia pachystachya, Citronella gongonha, Rapanea guianensis, Talauma ovata and Tapirira guianensis. A third group of transition between Semi-deciduous Forest and Forested Savanna, in intermediate altitude and soils less humid (species sampled in plots located at the edges of Swamp Forests), occurred both in the Forested Savanna and in Semi-deciduous Forest and a few in swampy environment. The highest percentages of sand in the soil of Pratinha, with less influence on water retention and also on the rates of fertility (alic soils, with greater acidity and less fertile), may explain some differences in the composition and abundance of species of forest physiognomies equal. The forested Savanna of Monte Belo, has proved floristically different from the Forested Savanna of Pratinha. This same difference occurred in swamp forests of Magnolia and Pratinha. The few species of common occurrence had differentpopulations. The CCA also revealed correlations of some species with certain variables of soil.
47

HARDWOOD REFORESTATION ON RECLAIMED MINELANDS IN THE EASTERN INTERIOR REGION: INTERACTIONS OF NURSERY STOCKTYPE, HERBICIDE, AND TREE SHELTERS ON RECLAMATION SUCCESS

Weston M. Schempf (5930837) 17 January 2019 (has links)
Reclamation of surface mined lands is required under the Surface Mining Control and Reclamation Act of 1977. Reforestation of mined lands is challenging due to harsh conditions such as soil compaction, herbaceous competition, and animal browse. We investigated the field performance of black walnut (<i>Juglans nigra</i>), northern red oak (<i>Quercus rubra</i>), and swamp white oak (<i>Quercus bicolor</i>) planted on two mine reclamation sites and evaluated the interactions of nursery stocktypes (container and bareroot), herbicide application, and tree shelters. Survival averaged 80% across all species and stocktypes after two years. Container stocktype had greater relative height and diameter growth, whereas bareroot had greater total height and diameter growth likely due to initial stocktype differences. Shelter use increased height growth and reduced diameter growth across both stocktypes. Swamp white oak (<i>Q. rubra</i>) had high survival and field performance regardless of silvicultural treatment, whereas the two other species showed strong early regeneration responses to silvicultural treatments. Container seedlings showed promise as an alternative to bareroot seedlings to promote survival and early growth on mine reclamation sites. Future research should be on continued development of container stocktypes to provide an economically feasible mine reclamation option for land managers.
48

Vliv rostlinné dominanty na C:N:P stechiometrii půdní organické hmoty a mikrobiální biomasy v rašelinných smrčinách / The influence of a plant dominant on C:N:P stoichiometry of soil organic matter and microbial biomass in peat spruce forests

PAVLÍKOVÁ, Lucie January 2015 (has links)
The aim of this report is to describe the elemental composition and C:N:P stoichiometry of soil organic matter and microbial biomass in spruce swamp forests in the National Park Šumava and to find out whether they are affected by a presence of different plant dominants in the understory - peat moss, cotton-grass and blueberry. Samplings were made at three locations in the spring, summer and autumn of 2013. The work was a part of the project funded by the GA CR.
49

Fatores abióticos definidores da distribuição dos diferentes tipos florestais (floresta paludícula, floresta estacional semidecídua ribeirinha e cerradão), nos municípios de Batatais e Restinga, SP / Abiotic factors determining the distribution of different types of forests (swamp forest, semi-deciduous riverine forest and forested savanna) in the cities of Batatais and Restinga, northeast of São Paulo State, in Brazil.

Vânia Korman 13 October 2008 (has links)
Com o objetivo de compreender quais fatores abióticos determinam a ocorrência das diferentes formações florestais na região de Batatais, entre as coordenadas 20038S e 20058S e 47037W e 47028W, foram escolhidas três propriedades agrícolas (Fazenda Monte Belo, em Restinga, SP e Fazenda Magnólia e Sítio Pratinha, em Batatais, SP), que apresentavam remanescentes florestais representativos da região (floresta ribeirinha paludícula, floresta estacional semidecídua ribeirinha e cerradão). Para descrever a composição florística e a estrutura da comunidade arbórea foram amostradas 05 parcelas de 10 x 10 m ao redor de cada estação tensiométrica. Para o estudo dos fatores abióticos foram determinados os parâmetros físicos e químicos dos solos e as curvas de retenção de água nos solos e piezometria. A discriminação das variáveis abióticas e de vegetação foi feita através da análise de componentes principais (PCA) e, na correlação entre a abundância de espécies e fatores abióticos, foram feitas análises diretas de gradiente por meio de Análise de Correlação Canônica (CCA). A textura dos solos (teores de argila, silte e areia) e a posição no terreno (cota), foram as variáveis ambientais mais importantes na distribuição das espécies e nas variações das fisionomias florestais, com influência na retenção hídrica e nos índices de fertilidade dos solos. Essas diferenças nos teores de argila em profundidade ao longo do declive, com influência direta na retenção de umidade dos solos ou mesmo na formação de ambientes paludículos, determinaram grupos distintos de espécies e fisionomias florestais: (i) um grupo de espécies de ocorrência típica nas fisionomias de Cerrado e fortemente associado às cotas mais elevadas (solos menos férteis, bem drenados e porcentagens mais baixas de argila e silte nas camadas mais profundas), entre as quais: Matayba juglandifolia, Trichilia pallida, Lithraea molleoides, Anadenanthera falcata, Myrcia tomentosa, Copaifera langsdorffii, Erytrhoxylum pelleteranum, Platipodium elegans, Chrysophyllum marginatum, Luehea divaricata, entre outras e (ii) um grupo com espécies indicadoras de Florestas Paludículas ou de ocorrência comum nestas fisionomias, associado aos solos das cotas mais baixas (Gleissolos), com porcentagens altas de argila e silte nas camadas superficiais, mais férteis e maior retenção hídrica: Cecropia pachystachya, Citronella gongonha, Rapanea guianensis, Talauma ovata e Tapirira guianensis. Pode-se considerar um terceiro grupo de transição entre Floresta Estacional Semidecídua e Cerradão, nas cotas intermediárias e menos úmidas (espécies amostradas em parcelas localizadas nas bordas das Florestas Paludículas), onde ocorreram espécies tanto de ambiente de Cerradão, como de Floresta Estacional Semidecídua, e algumas poucas de ambiente paludículo. As porcentagens mais elevadas de Areia nos solos do Sítio Pratinha, com influência na menor retenção hídrica e também nos índices de fertilidade (solos álicos, com maior acidez e os menos férteis), podem explicar algumas diferenças na composição e abundância das espécies entre fisionomias florestais iguais. O Cerradão da Fazenda Monte Belo, mostrou-se diferente floristicamente do Cerradão do Sítio Pratinha. Esta mesma diferença ocorreu em relação às Florestas Paludículas da Fazenda Magnólia e a do Sítio Pratinha. As poucasespécies de ocorrência comum tiveram populações diferentes. A CCA evidenciou também correlações de algumas espécies com determinadas variáveis de solo. / In order to understand what abiotic factors determine the occurrence of different forest formations in the region of Batatais, coordinated between 20038\'S and 20058\'S and 47037\'W and 47028\'W, three agricultural properties were chosen (Monte Belo, in the city of Restinga, SP and Magnolia and Pratinha in Batatais, SP, Brazil), which had forests representative of the region (swamp forest, semi-deciduous riverine forest and forested savanna). To describe the floristic composition and structure of the arboreal community, 05 plots of 10 x 10 meters around each tensiometric station were sampled. For the study of abiotic factors, the physico-chemical characteristics of the soils, the soil-water-retention curves and the groundwater fluctuation were determined. The discrimination of the environmental variables and arboreal species were made through the Principal Components Analysis (PCA), and in the correlation between the abundance of species and abiotic factors, direct analyses of gradient through Canonical Correspondence Analysis (CCA) were made. The texture of the soil (levels of clay, silt and sand) and the position on the ground (altitude) were the most important environmental variables in the distribution of species and variations of forest physiognomies, with influence in the retention rates of water and soil fertility. These differences in levels of clay in depth along the slope, with direct influence on the retention of soil moisture and even in the development of swampy environment, determined distinct groups of species and forest physiognomies: (i) a group of species of typical occurrence in physiognomies of Forested Savanna and strongly associated with higher altitude (less fertile, well-drained soil and lower percentages of clay and silt in the deeper layers), including: Matayba juglandifolia, Trichilia pallida, Lithraea molleoides, Anadenanthera falcata, Myrcia tomentosa, Copaifera langsdorffii, Erytrhoxylum pelleteranum, Platipodium elegans, Chrysophyllum marginatum, Luehea divaricata, among others, and (ii) a group with indicator species of Swamp Forests or common occurrence in these physiognomies, associated with lower altitude (Gleisoil), with high percentages of clay and silt in the upper and more fertile layers, and greater water retention: Cecropia pachystachya, Citronella gongonha, Rapanea guianensis, Talauma ovata and Tapirira guianensis. A third group of transition between Semi-deciduous Forest and Forested Savanna, in intermediate altitude and soils less humid (species sampled in plots located at the edges of Swamp Forests), occurred both in the Forested Savanna and in Semi-deciduous Forest and a few in swampy environment. The highest percentages of sand in the soil of Pratinha, with less influence on water retention and also on the rates of fertility (alic soils, with greater acidity and less fertile), may explain some differences in the composition and abundance of species of forest physiognomies equal. The forested Savanna of Monte Belo, has proved floristically different from the Forested Savanna of Pratinha. This same difference occurred in swamp forests of Magnolia and Pratinha. The few species of common occurrence had differentpopulations. The CCA also revealed correlations of some species with certain variables of soil.
50

Leis autorizativas para supressão de manguezais e as consequências socioambientais para o estado de Pernambuco

TAVARES, Patrícia Ferreira 05 March 2015 (has links)
Submitted by Irene Nascimento (irene.kessia@ufpe.br) on 2016-10-03T18:27:28Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) dissertação Patrícia Tavares - FINAL (Reparado).pdf: 1372192 bytes, checksum: f1841220d38eebee90f4380313bf2378 (MD5) / Made available in DSpace on 2016-10-03T18:27:28Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) dissertação Patrícia Tavares - FINAL (Reparado).pdf: 1372192 bytes, checksum: f1841220d38eebee90f4380313bf2378 (MD5) Previous issue date: 2015-03-05 / O presente trabalho buscou saber os prejuízos socioambientais decorrentes da eliminação do ecossistema manguezal, e se o Estado de Pernambuco está cumprindo o disposto na legislação ambiental quanto ao andamento do procedimento administrativo para supressão de vegetação considerada de Preservação Permanente. Como hipóteses, a pesquisadora elencou duas: considerando todos os benefícios decorrentes das funções ecológicas do ecossistema manguezal, o estado de Pernambuco perde drasticamente em termos de biodiversidade, que consequentemente desencadeia prejuízos socioambientais; e o Estado de Pernambuco incorre em ilegalidade e inconstitucionalidade na emissão de leis autorizativas para supressão de manguezal, descumprindo ainda princípios do direito ambiental. De acordo com os objetivos da pesquisa, realizou-se uma pesquisa documental/bibliográfica, quanto à legislação protetiva, à administração pública e aos procedimentos administrativos, inclusive ao nível nacional, para autorização de interferência no ecossistema e uma atualização das leis ordinárias com relação à autorização de supressão de áreas de manguezal no site da Assembleia Legislativa do Estado de Pernambuco. Tendo em vista que os pescadores, considerados comunidade tradicional, estão intrinsecamente ligados ao manguezal, foram realizadas 22 entrevistas com pescadores da colônia Z – 8, situada no município de Cabo de Santo Agostinho e 23 entrevistas com pescadoras da colônia Z-12, situada no município de Ipojuca. A atualização das leis autorizativas culminou com o resultado de 601,00 ha de manguezal autorizados a suprimir, o que desencadeou um verdadeiro desastre socioambiental, a partir da violação dos princípios ambientais e as disposições legais referentes. / The present study sought to know the social and environmental losses arising from the removal of mangrove swamp, and the state of Pernambuco is meeting the requirements of environmental legislation when the progress of the administrative procedure for removal of considered Permanent Preservation vegetation. As hypotheses, the researcher has listed two: considering all the benefits of the ecological functions of the mangrove ecosystem, the State of Pernambuco dramatically lose in terms of biodiversity, which in turn sets off sociambientais losses; and the State of Pernambuco incurs illegality and unconstitutionality in issuing authorization laws for suppression of mangrove swamp, still not complying with principles of environmental law. According to the research objectives, there was a documentary /bibliography research, about the protective legislation, public administration and administrative procedures, including the national level to permit interference in the ecosystem and an update to the ordinary laws regarding the authorization of removal of mangrove areas in Pernambuco State Legislative Assembly website. Having in mind that the traditional community - fishermen who are intrinsically linked to the mangrove swamp, there were 22 interviews with fishermen from the Z - 8 colony, located in the municipality of Cabo de Santo Agostinho and 23 interviews with fishers from the Z -12 colony, in the municipality of Ipojuca. Updating authorization acts culminated with the result of 601.00 ha of mangrove swamp allowed to suppress, which triggered a socioenvironmental disaster from the violation of environmental principles and legal provisions concerning.

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