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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.
11

Biotic and abiotic responses to rural development and legacy agriculture by southern Appalachain streams

Burcher, Chris L. 03 May 2005 (has links)
Streams are integrative systems spanning multiple spatial and temporal scales. Stream researchers, land-use managers, and policy decision makers must consider the downstream displacement of streams when approaching questions about stream ecosystems. The study of how anthropogenic land-use influences streams demands an ecosystem perspective, and this dissertation is an example of applying large scale analyses of stream reach responses, and linking the activity of humans in the landscape to stream structure and function. I investigate whether rural development and agriculture land-cover types influence abiotic and biotic stream responses. I establish a method for considering land-cover as an independent variable at multiple scales throughout a streams' watershed using hydraulic modeling. The travel time required for water to drain from the watershed to a stream reach provided a continuous index to delimit watershed sub portions along a spatial continuum. Within travel time zones (TTZs), I consider land-use at increasingly larger scales relative to a stream reach within which biotic responses are typically measured. By partitioning land-cover in TTZs, I was able to determine the spatial scale at which land-cover was most likely to influence in-stream responses. I quantified a suite of physical and biotic responses typical to the aquatic ecology literature, and found that streams did not respond much to rural development. Rural development influenced suspended and depositional sediments, and likely altered watershed hydrology though I was unable to find significant evidence supporting a hydrologic effect. Subtle differences in assemblages suggest that differences in sediment dynamics influenced macroinvertebrates and fish. Using the Land Cover Cascade (LCC) design, I link the influence of land-cover to biotic responses through a suite of multivariate models, focusing on sediment dynamics in an attempt to capture the subtle influence of hydrology and sediment dynamics. My dissertation provides future researchers with improved methods for considering land-cover as an independent variable, as well as introduces multivariate models that link land-cover to sediment dynamics and biota. My dissertation will assist future research projects in identifying specific mechanisms associated with stream responses to disturbance. / Ph. D.
12

Caracterização fisiográfica e pedológica da região norte do estado do Ceará /

Diniz, Simone Ferreira. January 2010 (has links)
Orientador: Jairo Roberto Jiménez Rueda / Banca: Juércio Tavares de Mattos / Banca: Arquimedes Peres Filho / Banca: Maria Margarita Torres Moreno / Banca: Miguel Cooper / Resumo: Os sucessivos eventos geológicos e ambientais estão representados na evolução da paisagem por meio de unidades fisiográficas e por meio de registros com interações de fatores e processos intensos. Deste modo, a caracterização e análise fisiográfica é ferramenta essencial no conhecimento desses eventos. Este trabalho visou o cruzamento de diversos dados físicos, químicos e mineralógicos da região Norte do Estado do Ceará e áreas homologas com informações espaciais (geomorfologia, pedologia, geologia, uso da terra, elevação e declividade) em ambiente CAD. A região Norte do Estado do Ceará é caracterizada por unidades policíclicas de origem marinha, paleo-marinha, paleo-fluvial, fluvial, estrutural e deposicional. Os solos estudados são desenvolvidos a partir do Grupo Serra Grande, Formação Barreiras e sedimentos inconsolidados. Para caracterizar as unidades fisiográficas e pedológicas foram realizadas coleta de amostras de solo e rocha, sendo processadas em laboratório para caracterizações físicas, químicas e mineralógicas. Nas superfícies fisiográficas foi possível identificar os vários processos que atuaram e atuam na evolução da paisagem. Os resultados permitiram avaliar a aplicação desta ferramenta no planejamento e gestão do meio físico e uso da terra de forma sustentável / Abstract: The successive geological events and environmental have been represented in the landscape by physiographic units and through records with factor interactions and intense process. Thus, the characterization, and physiographic analysis have been an essential tool in understanding and characterize these events. This work aimed the crossing of several physical, chemical and mineralogical data from the North river lower course and homologous areas with spatial information (geomorphology, pedology, geology, earth use, elevation and slope) in CAD environment for characterization evaluative and physiographic from the Ceará State. The north / northeast State of Ceará is characterized by polycyclic units of marine origin, palaeo-marine, palaeo-river, river, depositional and structural. The soils are developed from the Serra Grande Group, Training Barriers and unconsolidated sediments. To characterize the soil and physiographic units were collecting samples of soil and rock, being processed for physical characterizations, chemical and mineralogical. Physiographic surfaces was possible to identify the various processes that act and act in the evolution of the landscape. The results allowed evaluating the application of this tool in planning and managing the physical environment and earth use in a sustainable manner / Doutor
13

Aspectos fisiográficos do município de Rio Claro - SP /

Pupim, Fabiano do Nascimento. January 2010 (has links)
Resumo: Devido ao aumento da pressão antrópica sobre os ambientes naturais faz-se necessária a realização de levantamentos que contemplem diversos fatores ambientais (bióticos e abióticos) e corroborem com zoneamentos geoambientais e o planejamento territorial. O estudo da fisiografia permite a caracterização e classificação das paisagens terrestres levando em consideração os fatores formadores destas paisagens (clima atual e passado, hidrologia, geologia, geomorfologia e indiretamente aspectos bióticos) e as relações (processos) que os afetam. Desta forma, o objetivo da pesquisa foi investigar as características fisiográficas do município de Rio Claro-SP e, assim, contribuir para o melhor conhecimento dos aspectos do meio físico e suas relações. Para atingir o objetivo foram utilizados procedimentos e técnicas próprias das geociências, como interpretação de fotografias aéreas, geoprocessamento e levantamentos de campo. A sistemática de trabalho adotada se resume à quatro etapas: I) revisão bibliográfica; II) análise geomorfométrica; III) análise morfoestrutura e; IV) análise fisiográfica. Os resultados obtidos foram os mapas geomorfométricos (hipsometria, classes de declividade e curvatura do terreno), mapas morfoestruturais (lineamentos estruturais, traços de juntas, anomalias de drenagem e linhas de contorno estrutural não cotadas) e o mapa fisiográfico. A análise fisiográfica permitiu identificar e compreender os processos endógenos e exógenos que atuam e atuaram na evolução da paisagem. O município de Rio Claro-SP é caracterizado por paisagens policíclicas de origem fluvial, denudacional/paleoaluvial, denudacional e estrutural. A subdivisão das paisagens em unidades menores evidenciou a presença de subpaisagens do tipo planície de inundação e terraço para as paisagens fluviais; topos e encostas para as paisagens denudacionais/paleoaluviais, ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Due to the increase of anthropogenic pressure on natural environments it is necessary to make surveys involving several environmental factors (biotic and abiotic) and the corroborating with geoenvironmental zoning and land use planning. The study of the physiography enables the characterization and classification of landscapes, considering the factors of landscape formation (current and past climate, hydrology, geology, geomorphology and indirectly biotic aspects) and relations (processes) that affect them. Therefore, the aim of this research is to investigate the physiographic characteristics of Rio Claro-SP district and thus to contribute to a better knowledge of physical environment aspects and their relationships. To achieve the main objective specific techniques and procedures from geosciences were taken, such as aerial photo interpretation, geoprocessing and field surveys. The systematic adopted for this work followed four steps: i) reiew; II) geomorphometric analysis; III) morphostructural analysis; IV) physiographic analysis. The results gathered were the geomorphometric maps (hypsometry, slope and terrain curvature), morphostructural maps (structural lineaments, traces of joints, abnormal drainage and structural contour lines unlisted) and a physiographic map. Physiographic analysis allowed us to identify and understand the endogenous and exogenous processes that acted in landscape evolution. Rio Claro-SP is characterized by polycyclic landscapes with fluvial, denudational / paleoalluvial, denudational and structural origins. The subdivision of landscapes into smaller units showed the presence of sub-landscapes, from the type floodplain and river terrace landscapes; summit and slope to the landscapes denudational / paleoalluvial, denudational and structural; abandoned ponds in landscapes denudational / paleoalluvial / Orientador: Jairo Roberto Jiménez-Rueda / Coorientador: Juércio Tavares de Mattos / Banca: Tomoyuki Ohara / Banca: Sérgio dos Anjos Ferreira Pinto / Mestre
14

Edge habitats in agricultural landscapes : woody species, landscape ecology and implications for planning /

Sarlöv Herlin, Ingrid, January 1900 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 5 uppsatser.
15

The experience of pastoral landscapes /

Hägerhäll, Caroline, January 1900 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 5 uppsatser och 1 bildbil.
16

Population processes in heterogenous landscapes /

Westerberg, Lars, January 2004 (has links) (PDF)
Diss. (sammanfattning) Linköping : Univ., 2004. / Härtill 4 uppsatser.
17

Sensibilidade ambiental a hidrocarbonetos para rodovias: estudo de caso em trecho da Rodovia Anhanguera (SP-330) / Environmental sensitivity to hydrocarbons for highways: a case study of the Anhanguera Highway (SP-330)

Ferreira, Mayara Nicolau [UNESP] 26 October 2017 (has links)
Submitted by Mayara Nicolau Ferreira null (mayara_feni@outlook.com) on 2017-12-13T19:33:50Z No. of bitstreams: 1 Dissertação final para o cd.pdf: 8263943 bytes, checksum: a933228a9bd4ca5a348d316c828ae92d (MD5) / Submitted by Mayara Nicolau Ferreira null (mayara_feni@outlook.com) on 2017-12-14T11:25:01Z No. of bitstreams: 1 Dissertação final para o cd.pdf: 8263943 bytes, checksum: a933228a9bd4ca5a348d316c828ae92d (MD5) / Submitted by Mayara Nicolau Ferreira null (mayara_feni@outlook.com) on 2017-12-14T13:50:30Z No. of bitstreams: 1 Dissertação final para o cd.pdf: 8263943 bytes, checksum: a933228a9bd4ca5a348d316c828ae92d (MD5) / Approved for entry into archive by Adriana Aparecida Puerta null (dripuerta@rc.unesp.br) on 2017-12-14T16:02:31Z (GMT) No. of bitstreams: 1 ferreira_mn_me_rcla.pdf: 8244618 bytes, checksum: f6eec6ad55c4fa070d073f0df07c532a (MD5) / Made available in DSpace on 2017-12-14T16:02:31Z (GMT). No. of bitstreams: 1 ferreira_mn_me_rcla.pdf: 8244618 bytes, checksum: f6eec6ad55c4fa070d073f0df07c532a (MD5) Previous issue date: 2017-10-26 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Considerando o crescente número de acidentes com produtos perigosos em rodovias e que este é o modal mais utilizado para o transporte de cargas no Brasil, principalmente hidrocarbonetos e derivados de petróleo. Bem como, os insipientes estudos de índices de sensibilidade ambiental para ambientes terrestres. E que os mapas de sensibilidade são importantes ferramentas técnico-gerenciais utilizadas na tomada de decisões emergenciais em caso de combate a derrames de óleo. Além de fornecer informações para o planejamento de contenção e limpeza para mitigar os impactos ambientais, auxiliar a identificação de locais sensíveis antes que ocorra o acidente, de modo que as estratégias de proteção e contenção possam ser organizadas antecipadamente, objetiva-se a confecção de um índice de sensibilidade ambiental aos hidrocarbonetos para rodovias, utilizando como área de estudo um trecho da Rodovia Anhanguera (SP-330), segunda maior em números de acidentes com produtos perigosos no estado de São Paulo, e sua respectiva carta de sensibilidade ambiental. Para tanto, procede-se fazendo uso de geotecnologias para confecção de mapas básicos necessários a pesquisa; da compartimentação fisiográfica para dividir a área de estudo em zonas homólogas; do trabalho de campo para corroborar a compartimentação; da escolha dos cinco parâmetros e seus respectivos pesos, que compõem o índice de sensibilidade ambiental aos hidrocarbonetos para rodovias; e consequentemente, a confecção da carta de sensibilidade ambiental. Desse modo, observa-se que no trecho foram encontrados os índices 5, 7 e 8, sendo que o índice 7 é predominante em seis das oito Unidade Básicas de Compartimentação, o que permite concluir que a área estudada tem média-alta sensibilidade ambiental, levando em consideração que o índice vai de 1 a 10 A. Além de colaborar com o desenvolvimento de uma adaptação do método das cartas SAO utilizadas em ambientes costeiros e fluviais para um índice de sensibilidade ambiental aos hidrocarbonetos para rodovias. Por fim, conclui-se que o mapeamento de sensibilidade ambiental aos hidrocarbonetos para o modal rodoviário apresenta-se viável a partir da aplicação de um método adequado ao ambiente em que está inserido e o método da compartimentação fisiográfica foi extremamente apropriado e eficaz para os ambientes terrestres. / Considering the increasing number of accidents with hazardous products on highways and that this is the most used modal for the transport of cargoes in Brazil, mainly hydrocarbons and petroleum products. As well as, the insipient studies of environmental sensitivity indexes for terrestrial environments. And that sensitivity maps are important technical and managerial tools used in making emergency decisions in case of combating oil spills. In addition to providing information for containment and cleanup planning to mitigate environmental impacts, assisting the identification of sensitive locations before the accident occurs, so that protection and containment strategies can be organized in advance, it is aimed to create an Index of environmental sensitivity to hydrocarbons for highways, using as an area of study a section of the Anhanguera Highway (SP-330), second largest in numbers of accidents with dangerous products in the state of São Paulo, and its respective letter of environmental sensitivity. To do so, we make use of geotechnologies to create basic maps necessary for the research; the physiographic compartmentalization to divide the study area into homologous zones; the fieldwork to corroborate the compartmentalization; the choice of the five parameters and their respective weights, which make up the environmental sensitivity index for hydrocarbons for highways; and consequently, the preparation of the environmental sensitivity letter. Therefore, it can be observed that the indexes 5, 7 and 8 were found in this section, with index 7 being predominant in six of the eight Basic Compartmental Units, which allows to conclude that the studied area has medium-high environmental sensitivity, taking into account that the index ranges from 1 to 10 A. In addition to collaborating with the development of an adaptation of the SAO letters used in coastal and fluvial environments to an environmental sensitivity index to hydrocarbons for highways. Finally, it is concluded that the mapping of environmental sensitivity to hydrocarbons for the road modal is feasible from the application of a method appropriate to the environment in which it is inserted and the physiographic compartmentalization method was extremely appropriate and effective for the land environments.
18

Caracterização fisiográfica e pedológica da região norte do estado do Ceará

Diniz, Simone Ferreira [UNESP] 24 September 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:20Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-09-24Bitstream added on 2014-06-13T19:42:52Z : No. of bitstreams: 1 diniz_sf_dr_rcla.pdf: 2299796 bytes, checksum: 7363e7fecd715b9830dc5c4946f53710 (MD5) / Os sucessivos eventos geológicos e ambientais estão representados na evolução da paisagem por meio de unidades fisiográficas e por meio de registros com interações de fatores e processos intensos. Deste modo, a caracterização e análise fisiográfica é ferramenta essencial no conhecimento desses eventos. Este trabalho visou o cruzamento de diversos dados físicos, químicos e mineralógicos da região Norte do Estado do Ceará e áreas homologas com informações espaciais (geomorfologia, pedologia, geologia, uso da terra, elevação e declividade) em ambiente CAD. A região Norte do Estado do Ceará é caracterizada por unidades policíclicas de origem marinha, paleo-marinha, paleo-fluvial, fluvial, estrutural e deposicional. Os solos estudados são desenvolvidos a partir do Grupo Serra Grande, Formação Barreiras e sedimentos inconsolidados. Para caracterizar as unidades fisiográficas e pedológicas foram realizadas coleta de amostras de solo e rocha, sendo processadas em laboratório para caracterizações físicas, químicas e mineralógicas. Nas superfícies fisiográficas foi possível identificar os vários processos que atuaram e atuam na evolução da paisagem. Os resultados permitiram avaliar a aplicação desta ferramenta no planejamento e gestão do meio físico e uso da terra de forma sustentável / The successive geological events and environmental have been represented in the landscape by physiographic units and through records with factor interactions and intense process. Thus, the characterization, and physiographic analysis have been an essential tool in understanding and characterize these events. This work aimed the crossing of several physical, chemical and mineralogical data from the North river lower course and homologous areas with spatial information (geomorphology, pedology, geology, earth use, elevation and slope) in CAD environment for characterization evaluative and physiographic from the Ceará State. The north / northeast State of Ceará is characterized by polycyclic units of marine origin, palaeo-marine, palaeo-river, river, depositional and structural. The soils are developed from the Serra Grande Group, Training Barriers and unconsolidated sediments. To characterize the soil and physiographic units were collecting samples of soil and rock, being processed for physical characterizations, chemical and mineralogical. Physiographic surfaces was possible to identify the various processes that act and act in the evolution of the landscape. The results allowed evaluating the application of this tool in planning and managing the physical environment and earth use in a sustainable manner
19

Suscetibilidade a escorregamentos na região entre Caraguatatuba e São Sebastião (SP): análise fisiográfica e quantitativa / Susceptibility to landslides in the region between Caraguatatuba and São Sebastião (SP): physiographic and quantitative analysis

Gabelini, Beatriz Marques [UNESP] 30 June 2017 (has links)
Submitted by BEATRIZ MARQUES GABELINI null (bgabelini@gmail.com) on 2017-08-31T17:47:38Z No. of bitstreams: 1 Dissertação GABELINI, B M 2017.pdf: 19236253 bytes, checksum: f945ee682ee01330adc9122af7b4b3dd (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-08-31T19:36:46Z (GMT) No. of bitstreams: 1 gabelini_bm_me_rcla.pdf: 19236253 bytes, checksum: f945ee682ee01330adc9122af7b4b3dd (MD5) / Made available in DSpace on 2017-08-31T19:36:46Z (GMT). No. of bitstreams: 1 gabelini_bm_me_rcla.pdf: 19236253 bytes, checksum: f945ee682ee01330adc9122af7b4b3dd (MD5) Previous issue date: 2017-06-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os escorregamentos são movimentos de massa recorrentes na Serra do Mar. Quando ocorrem de forma generalizada podem causar prejuízos e perdas de vidas, como no acidente ocorrido no município de Caraguatatuba (SP) em 1967. Com o intuito de evitar estes danos, na literatura, são propostos vários métodos para analisar e prever a ocorrência destes processos. Diante do exposto, o objetivo principal desta pesquisa consiste em analisar a suscetibilidade a escorregamentos na região entre Caraguatatuba e São Sebastião (SP), utilizando a compartimentação fisiográfica e a análise quantitativa. Para alcançar estes objetivos foi realizada a análise e compartimentação do terreno e a análise quantitativa dos fatores condicionantes (declividade, hipsometria e geologia) e da compartimentação fisiográfica. Foram testados, em ambiente SIG, diversos cenários a partir de dois métodos distintos. No Método 1, os fatores condicionantes foram analisados através de pesos de influência. No Método 2, os fatores condicionantes mantiveram os mesmos pesos do Método 1 e foram somados pesos para as classes de cada fator. A compartimentação fisiográfica definiu 16 unidades. Os resultados demonstraram que a maioria dos escorregamentos se concentraram na unidade fisiográfica IV e que há um controle topográfico na distribuição dos escorregamentos entre 100 e 400 m de altitude, em encostas com declividade entre 15º e 30º, compostas por gnaisse migmatítico e granito-gnaisse. Os mapas elaborados a partir do Método 2 apresentaram expressiva concordância com o mapeamento de cicatrizes de Fúlfaro et al. (1976). O cenário escolhido como mais coerente foi o Cenário O, em que houve 60% de influência da declividade, 30% de hipsometria e 10% de geologia. Portanto, a partir do estudo da suscetibilidade, por meio da análise fisiográfica e quantitativa, é possível afirmar que o fator que tem mais influência na ocorrência de escorregamentos, na área de estudo, é a declividade, seguida da hipsometria e geologia. / Landslides are recurrent mass movements in the Serra do Mar. When they occur in a generalized way, as in the event occurred in Caraguatatuba city (SP) in 1967, they can cause a lot of environmental damage and deaths. In order to avoid this damage, several methods were proposed to analyze and predict the occurrence of this process. Considering the above, the main objective of this research is to analyze the susceptibility to landslides in the region between Caraguatatuba and São Sebastião (SP), using physiographic compartmentalization and quantitative analysis. In order to achieve these objectives, a physiographic analysis of the study area was carried out by the method of physiographic compartmentalization. Topographic and geological factors, as well as a physiographic comparison were analyzed using percentages of Class Frequency, Scars Concentration and Disproportionality Factor. We tested several scenarios from two different methods in a GIS environment. Method 1 by which the conditioning factors were analyzed through influence weights and Method 2, which maintains the influence weight for the factors and includes weights to the classes of each factor. The physiographic compartmentalization defined 16 units. Our results showed that most of the landslides were concentrated in the Physiographic Unit IV, and a topographic control in the distribution of landslides between 100 and 400 m of altitude, in slopes with declivity between 15 and 30º, composed of migmatite gneiss and granite-gneiss. Method 2 presented significant agreement with the scar mapping of Fúlfaro et al. (1976), and the scenario chosen as more coherent was Scenario O, which presented 60% influence of declivity, 30% hypsometry and 10% geology. The application of the different methods was satisfactory and based on the results we considered the utilization of the physiographic compartmentalization and the probabilistic analysis as important tools in the prediction of susceptibility, thus being able to collaborate with the territorial and environmental management of the cities.
20

Characterizing and modeling wet stream length dynamics in Appalachian headwaters

Jensen, Carrie Killeen 03 May 2018 (has links)
Headwater streams change in wet length in response to storm events and seasonal moisture conditions. These low-order channels with temporary flow are pervasive across arid and humid environments yet receive little attention in comparison to perennial waterways. This dissertation examines headwater stream length dynamics at multiple spatial and temporal scales across the Appalachians. I mapped wet stream length in four Appalachian physiographic provinces--the Appalachian Plateau, Blue Ridge, New England, and Valley and Ridge--to characterize seasonal expansion and contraction of the wet network at a broad, regional scale. Conversely, most existing field studies of stream length in headwaters are limited to a single study area or geographic setting. Field mappings showed that wet stream length varies widely within the Appalachians; network dynamics correlated with regional geology as well as local site lithology, geologic structure, and the depth, size, and spatial distribution of surficial sediment deposits. I used the field data to create logistic regression models of the wet network in each physiographic province at high and low runoffs. Topographic metrics derived from elevation data were able to explain the discontinuous pattern of headwater streams at different flow conditions with high classification accuracy. Finally, I used flow intermittency sensors in a single Valley and Ridge catchment to record channel wetting and drying at a high temporal resolution. The sensors indicated stream length hysteresis during storms with low antecedent moisture, with a higher wet network proportion on the rising limb than on the falling limb of events. As a result, maximum network extension can precede peak runoff by minutes to hours. Accurate maps of headwater streams and an understanding of wet network dynamics through time are invaluable for applications surrounding watershed management and environmental policy. These findings will contribute to the burgeoning research on temporary streams and are additionally relevant for studies of runoff generation, biogeochemical cycling, and mass fluxes of material from headwaters. / Ph. D.

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