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Geotecnologias aplicadas à análise espaço temporal do uso e cobertura da terra e qualidade da água do reservatório de Barra Bonita, SP, como suporte à gestão de recursos hídricos ; Geotechnologies applied to spatial and temporal analysis of the land use and land cover basin related to the water quality Barra Bonita reservoir to support water resources management

Prado, Rachel Bardy
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 10/09/2004 PT
Relevância na Pesquisa
66.54%
Perante a situação atual de degradação dos recursos hídricos, destacando os reservatórios destinados a usos múltiplos, e a necessidade de se buscar soluções para tal problema, foi proposto o presente trabalho. O reservatório de Barra Bonita, localizado no interior do Estado de São Paulo, foi escolhido para estudo, por estar inserido em uma área densamente povoada, industrializada e ocupada por agricultura intensiva. Os dados adquiridos foram de natureza cartográfica (cartas de pedologia, geomorfologia, geologia, drenagem e malha municipal); orbitais (imagens multiespectrais dos satélites Landsat 5 e 7); censitários (produção agrícola municipal e densidade demográfica); limnológicos (característicasfísicas, químicas e biológicas do reservatório estudado, obtidas em campo e na literatura); pluviométricos e fluviométricos. A organização e o tratamento das diversas informações foram realizados com o auxílio de Sistema de Informação Geográfica (Spring 3.6), obtendo também um banco de dados limnológicos multitemporal. As ferramentas de geotecnologias foram aplicadas na caracterização dos fatores fisiográficos, no mapeamento do uso e cobertura da terra e do potencial poluidor das sub-bacias da bacia de drenagem...

Diagnóstico ambiental e análise temporal da adequabilidade do uso e cobertura do solo na bacia do Ribeirão dos Marins, Piracicaba - SP; Environmental diagnostic and temporal analysis of the suitability of the land use and land cover in the “Ribeirão dos Marins” basin, Piracicaba - SP

Casagrande, Catia Andersen
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 28/09/2005 PT
Relevância na Pesquisa
66.58%
O diagnóstico ambiental e a análise da adequabilidade da ocupação permitem a identificação de áreas mais críticas quanto ao nível de degradação, sendo extremamente relevantes para o estabelecimento de medidas de preservação, conservação e recuperação. Este trabalho teve como objetivo realizar um diagnóstico ambiental e analisar a adequabilidade do uso e cobertura do solo da bacia hidrográfica do ribeirão dos Marins ao longo do tempo e sua influência sobre os recursos hídricos, considerando a legislação vigente, através de técnicas de geoprocessamento. Foram realizadas as análises das mudanças que ocorreram na bacia, da adequabilidade do uso e cobertura do solo e das relações entre alguns aspectos considerados no trabalho. As análises envolveram aspectos relacionados à qualidade da água, ao uso e cobertura do solo, a estrutura da paisagem, ao risco de erosão, a capacidade do uso do solo e a adequabilidade do uso do solo quanto às limitações devido ao risco de erosão, as condições das Áreas de Preservação Permanente (APPs) e ao Código Florestal. Constatou-se que os recursos hídricos da bacia estão sendo degradados, o uso e cobertura do solo está inadequado e um processo de fragmentação está ocorrendo na paisagem. Fontes potenciais de contaminação dos recursos naturais foram identificadas na bacia...

Mudanças no uso e cobertura do solo e resposta hidrológica da bacia do rio Piracicaba; Land use/land cover changes and hydrological response in the Piracicaba river basin

Caram, Rochane de Oliveira
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 25/02/2011 PT
Relevância na Pesquisa
66.58%
Este estudo objetivou avaliar o efeito das mudanças no uso e cobertura do solo nos últimos 37 anos (1972 a 2008) na resposta hidrológica da bacia do rio Piracicaba, SP. As principais mudanças de uso e cobertura do solo na bacia neste período foram aumento da área urbana, redução da área de pastagem e aumento do plantio de canade- açúcar. Além disso, a bacia conta com uma peculiaridade, que é a presença do Sistema Cantareira, que desvia água à região metropolitana de São Paulo (RMSP), desde 1974. Foi utilizado o Modelo Hidrológico de Grandes Bacias (MGB), que tem a vantagem de avaliar de forma distribuída a variação da cobertura, do tipo e uso do solo, além da própria propagação no escoamento. O modelo foi ajustado à bacia do rio Piracicaba (área de 12.245 km2) para simulação de vazões diárias. Para o processo de ajuste do modelo foram utilizados dados diários de 1972 a 2008, de 12 postos fluviométricos, 61 pluviométricos e 20 meteorológicos, modelo numérico do terreno, mapas de solos e uso e cobertura do solo (para os anos: 1978, 1983, 1985, 1997 e 2003), e parâmetros que são importantes para diferenciar tipos de solo e usos e coberturas do solo. O processo de simulação das vazões foi realizado em duas etapas: calibração dos parâmetros (entre 1972 a 1990) e verificação (1991 a 2008). Para avaliação da qualidade de ajuste foi considerada a análise visual dos hidrogramas (vazões observadas e calculadas) e os valores das funções objetivo (R2...

Impactos das atualizações do uso e cobertura da terra e das características físico-químicas da vegetação na América do Sul em modelos climáticos; Impacts caused by updating the land use and land cover and the physical-chemical properties of vegetation to South America in climatic models

Pereira, Gabriel
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 09/11/2012 PT
Relevância na Pesquisa
66.57%
As mudanças de uso e cobertura da terra ocasionam alterações no balanço de energia, na temperatura do ar, na precipitação, na umidade do ar e na circulação regional e global. Consequentemente, mapas de uso e cobertura da terra e suas respectivas características físico-químicas e biológicas constituem-se em uma importante variável na modelagem numérica de sistemas terrestres. Entretanto, na maioria dos modelos regionais de previsão do tempo e clima, o mapa de uso e cobertura da terra não é atualizado com frequência e encontra-se defasado, o que influencia os resultados das simulações. Desta forma, o presente trabalho tem como objetivo principal verificar o impacto nas simulações numéricas do RegCM4 oriundas da atualização do mapa de uso e cobertura da terra e dos parâmetros físicos como, por exemplo, o índice de área foliar (IAF), a reflectância no visível ( 0,7m) e no infravermelho próximo e médio (>0,7m) utilizados pelo Biosphere Atmosphere Transfer Scheme (BATS), além da validação dos dados provenientes do Tropical Rainfall Measuring Mission (TRMM). Consequentemente, a comparação entre os dados de precipitação mensal estimada pelo TRMM e 183 estações meteorológicas espalhadas por todo o Brasil apresentam uma concordância de aproximadamente 97%. Ainda...

Wildfire selectivity for land cover type: does size matter ?

Barros, Ana M.G.; Pereira, J.M.C.
Fonte: Gil Bohrer, The Ohio State University, USA Publicador: Gil Bohrer, The Ohio State University, USA
Tipo: Artigo de Revista Científica
Publicado em //2014 ENG
Relevância na Pesquisa
66.55%
Previous research has shown that fires burn certain land cover types disproportionally to their abundance. We used quantile regression to study land cover proneness to fire as a function of fire size, under the hypothesis that they are inversely related, for all land cover types. Using five years of fire perimeters, we estimated conditional quantile functions for lower (avoidance) and upper (preference) quantiles of fire selectivity for five land cover types - annual crops, evergreen oak woodlands, eucalypt forests, pine forests and shrublands. The slope of significant regression quantiles describes the rate of change in fire selectivity (avoidance or preference) as a function of fire size. We used Monte-Carlo methods to randomly permutate fires in order to obtain a distribution of fire selectivity due to chance. This distribution was used to test the null hypotheses that 1) mean fire selectivity does not differ from that obtained by randomly relocating observed fire perimeters; 2) that land cover proneness to fire does not vary with fire size. Our results show that land cover proneness to fire is higher for shrublands and pine forests than for annual crops and evergreen oak woodlands. As fire size increases, selectivity decreases for all land cover types tested. Moreover...

Spatio-temporal land use/land cover changes analysis and monitoring in the Valencia Municipality, Spain

Yesserie, Addis Getnet
Fonte: Universidade Nova de Lisboa Publicador: Universidade Nova de Lisboa
Tipo: Dissertação de Mestrado
Publicado em 06/03/2009 ENG
Relevância na Pesquisa
66.52%
Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies; Issues of land use/land cover changes and the direct or indirect relationships of these changes have drawn much attention in recent years. In the Mediterranean Spain, observed environmental changes influenced with dramatic urban growth and their likely changes can have extensive unforeseen ramification. Thus, the objectives of this research were to map and determine the nature, extent and rate of changes and to analyze the spatio-temporal land use/land cover change patterns and fragmentation that has occurred in Valencia Municipality. Multi-temporal Landsat MSS1976, TM1992 and ETM2001 images were acquired. Digital orthophotos, IKONOS images and existing Corine land cover maps were used as reference. More than 130 training samples were selected for classification of the Landsat images using supervised method parallelepiped-maximum likelihood algorithm in ERDAS Imagine 9.1, and land cover maps were generated and change detection analysis was performed.(...)

Estimation of vegetation carbon stock in Portugal using land use/ land cover data

Molin, Paulo Guilherme
Fonte: Universidade Nova de Lisboa Publicador: Universidade Nova de Lisboa
Tipo: Dissertação de Mestrado
Publicado em 02/03/2010 ENG
Relevância na Pesquisa
66.56%
Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies; This research aimed to quantify the carbon stored over the years in vegetation throughout Continental Portugal. Carbon stock was measured for the years of 1985, 2000 and 2006. For this, the CORINE (Co-Ordination of Information on the Environment) Land Cover (CLC) database was used to estimate the spatial distribution and quantity of carbon stored by each land cover class. Carbon stock was the result of each CORINE land cover class area multiplied by its respective carbon density. Densities were derived from literature, namely Portuguese Environmental Agency tables. Results show a decrease of carbon stock for the time lapse of both 1985-2000 and 2000-2006. The year 1985 had a total carbon stock of 173.08 Mt, 2000 resulted in a total of 170.22 Mt and finally the year 2006 with 159.97 Mt. Spatial distribution of the carbon stock was also verified as well as the statistics per class. Results show that the gathering of carbon stock records is a key step in monitoring changes in carbon sequestration. By using CORINE land cover as a default database, this methodology may be used by other countries members of the CORINE program and therefore may be easily comparable in between them. In another approach...

The contribution of multitemporal information from multispectral satellite images for automatic land cover classification at the national scale

Carrão, Hugo Miguel Saiote
Fonte: Universidade Nova de Lisboa Publicador: Universidade Nova de Lisboa
Tipo: Tese de Doutorado
Publicado em 27/01/2010 ENG
Relevância na Pesquisa
66.62%
Thesis submitted to the Instituto Superior de Estatística e Gestão de Informação da Universidade Nova de Lisboa in partial fulfillment of the requirements for the Degree of Doctor of Philosophy in Information Management – Geographic Information Systems; Imaging and sensing technologies are constantly evolving so that, now, the latest generations of satellites commonly provide with Earth’s surface snapshots at very short sampling periods (i.e. daily images). It is unquestionable that this tendency towards continuous time observation will broaden up the scope of remotely sensed activities. Inevitable also, such increasing amount of information will prompt methodological approaches that combine digital image processing techniques with time series analysis for the characterization of land cover distribution and monitoring of its dynamics on a frequent basis. Nonetheless, quantitative analyses that convey the proficiency of three-dimensional satellite images data sets (i.e. spatial, spectral and temporal) for the automatic mapping of land cover and land cover time evolution have not been thoroughly explored. In this dissertation, we investigate the usefulness of multispectral time series sets of medium spatial resolution satellite images for the regular land cover characterization at the national scale. This study is carried out on the territory of Continental Portugal and exploits satellite images acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) and MEdium Resolution Imaging Spectrometer (MERIS). In detail...

Urban land cover change detection analysis and modeling spatio-temporal Growth dynamics using Remote Sensing and GIS Techniques: A case study of Dhaka, Bangladesh

Ahmed, Bayes
Fonte: Universidade Nova de Lisboa Publicador: Universidade Nova de Lisboa
Tipo: Dissertação de Mestrado
Publicado em 07/03/2011 ENG
Relevância na Pesquisa
66.55%
Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies.; Dhaka, the capital of Bangladesh, has undergone radical changes in its physical form, not only in its vast territorial expansion, but also through internal physical transformations over the last decades. In the process of urbanization, the physical characteristic of Dhaka is gradually changing as open spaces have been transformed into building areas, low land and water bodies into reclaimed builtup lands etc. This new urban fabric should be analyzed to understand the changes that have led to its creation. The primary objective of this research is to predict and analyze the future urban growth of Dhaka City. Another objective is to quantify and investigate the characteristics of urban land cover changes (1989-2009) using the Landsat satellite images of 1989, 1999 and 2009. Dhaka City Corporation (DCC) and its surrounding impact areas have been selected as the study area. A fisher supervised classification method has been applied to prepare the base maps with five land cover classes. To observe the change detection, different spatial metrics have been used for quantitative analysis. Moreover, some postclassification change detection techniques have also been implemented. Then it is found that the ‘builtup area’ land cover type is increasing in high rate over the years. The major contributors to this change are ‘fallow land’ and ‘water body’ land cover types. In the next stage...

Analysis of urban land use and land cover changes: a case of study in Bahir Dar, Ethiopia

Sahalu, Atalel Getu
Fonte: Universidade Nova de Lisboa Publicador: Universidade Nova de Lisboa
Tipo: Dissertação de Mestrado
Publicado em 28/02/2014 ENG
Relevância na Pesquisa
66.65%
Dissertation submitted in partial fulfillment of the requirements for the Degree of Master of Science in Geospatial Technologies; The high rate of urbanization coupled with population growth has caused changes in land use and land cover in Bahir Dar, Ethiopia. Therefore, understanding and quantifying the spatio- temporal dynamics of urban land use and land cover changes and its driving factors is essential to put forward the right policies and monitoring mechanisms on urban growth for decision making. Thus, the objective of this study was to analyze land use and land cover changes in Bahir Dar area, Ethiopia by applying geospatial and land use change modeling tools. In order to achieve this, satellite data of Landsat TM for 1986 and ETM for 2001 and 2010 have been obtained and preprocessed using ArcGIS. The Maximum Liklihood Algorithm of Supervised Classification has been used to generate land use and land cover maps. For the accuracy of classified land use and land cover maps, a confusion matrix was used to derive overall accuracy and results were above the minimum and acceptable threshold level. The generated land cover maps have been run with Land Change Modeler for quantifying land use and land cover changes, to examine land use transitions between land cover classes...

A comparative analysis of ALOS PALSAR L-band and RADARSAT-2 C-band data for land-cover classification in a tropical moist region.

LI, G.; LU, D.; DUTRA, L.; BATISTELLA, M.
Fonte: ISPRS Journal of Photogrammetry and Remote Sensing, v. 70, p. 26-38, 2012. Publicador: ISPRS Journal of Photogrammetry and Remote Sensing, v. 70, p. 26-38, 2012.
Tipo: Artigo em periódico indexado (ALICE) Formato: p. 26-38.
EN
Relevância na Pesquisa
66.54%
This paper explores the use of ALOS (Advanced Land Observing Satellite) PALSARL-band (Phased Array type L-band Synthetic Aperture Radar) and RADARSAT-2 C-band data for land-cover classification in a tropical moist region. Transformed divergence was used to identify potential textural images which were calculated with the gray-level co-occurrence matrix method. The standard deviation of selected textural images and correlation coefficients between them were then used to determine the best combination of texture images for land-cover classification. Classification results based on different scenarios with maximum likelihood classifier were compared. Based on the identified best scenarios, different classification algorithms ? maximum likelihood classifier, classification tree analysis, Fuzzy ARTMAP (a neural-network method), k-nearest neighbor, object-based classification, and support vector machine were compared for examining which algorithm was suitable for land-cover classification in the tropical moist region. This research indicates that the combination of radiometric images and their textures provided considerably better classification accuracies than individual datasets. The L-band data provided much better landcover classification than C-band data but neither L-band nor C-band was suitable for fine land-cover classification system...

A land cover map of South America.

EVA, H. D.; BELWARD, A. D.; MIRANDA, E. E. de; DI BELLA, C. M.; GONDS, V.; HUBER, O.; JONES, S.; SGRENZAROLI, M.; FRITZ, S.
Fonte: Global Change Biology, Oxford-Inglaterra, v. 10, p. 1-14, 2004. Publicador: Global Change Biology, Oxford-Inglaterra, v. 10, p. 1-14, 2004.
Tipo: Artigo em periódico indexado (ALICE)
EN
Relevância na Pesquisa
66.51%
A digital land cover map of South America has been produced using remotely sensed satellite data acquired between 1995 and the year 2000. The mapping scale is defined by the 1 km spatial resolution of the map grid-cell. In order to realize the product, different sources of satellite data were used, each source providing either a particular parameter of land cover characteristic required by the legend, or mapping a particular land cover class. The map legend is designed both to fit requirements for regional climate modelling and for studies on land cover change. The legend is also compatible with a wider, global, land cover mapping exercise, which seeks to characterize the world?s land surface for the year 2000. As a first step, the humid forest domain has been validated using a sample of high-resolution satellite images. The map demonstrates both the major incursions of agriculture into the remaining forest domains and the extensive areas of agriculture, which now dominate South America?s grasslands.; 2004

Larval habitat associations with human land uses, roads, rivers, and land cover for Anopheles albimanus, A. pseudopunctipennis, and A. punctimacula (Diptera: Culicidae) in coastal and highland Ecuador

Pinault, Lauren L.; Hunter, Fiona F.
Fonte: Frontiers Publicador: Frontiers
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
66.52%
Larval habitat for three highland Anopheles species: Anopheles albimanus Wiedemann, Anopheles pseudopunctipennis Theobald, and Anopheles punctimacula Dyar and Knab was related to human land uses, rivers, roads, and remotely sensed land cover classifications in the western Ecuadorian Andes. Of the five commonly observed human land uses, cattle pasture (n = 30) provided potentially suitable habitat for A. punctimacula and A. albimanus in less than 14% of sites, and was related in a principal components analysis (PCA) to the presence of macrophyte vegetation, greater surface area, clarity, and algae cover. Empty lots (n = 30) were related in the PCA to incident sunlight and provided potential habitat for A. pseudopunctipennis and A. albimanus in less than 14% of sites. The other land uses surveyed (banana, sugarcane, and mixed tree plantations; n = 28, 21, 25, respectively) provided very little standing water that could potentially be used for larval habitat. River edges and eddies (n = 41) were associated with greater clarity, depth, temperature, and algae cover, which provide potentially suitable habitat for A. albimanus in 58% of sites and A. pseudopunctipennis in 29% of sites. Road-associated water bodies (n = 38) provided potential habitat for A. punctimacula in 44% of sites and A. albimanus in 26% of sites surveyed. Species collection localities were compared to land cover classifications using Geographic Information Systems software. All three mosquito species were associated more often with the category “closed/open broadleaved evergreen and/or semi-deciduous forests” than expected (P ≤ 0.01 in all cases)...

Assessment of land cover changes and their effect on soil organic carbon and soil total nitrogen in Daqing Prefecture, China

Yu, B.; Stott, P.; Di, X.; Yu, H.
Fonte: John Wiley & Sons Ltd Publicador: John Wiley & Sons Ltd
Tipo: Artigo de Revista Científica
Publicado em //2014 EN
Relevância na Pesquisa
66.51%
The aim of this study was to examine the influence of land cover changes on soil organic carbon (SOC) and soil total nitrogen (STN) in the Daqing Prefecture of China, where heavy industrialisation in the form of dense oil wells has impacted the environment. Time-series presentations for the period 1978 to 2008 of remotely sensed data and soil survey data were used to assess the extent of the changes. The study revealed soil degradation under all land cover types and in all soil types, grassland retreat (−15 per cent), swampland retreat (−45 per cent) and increases in the area of farmland (+19 per cent), sand land (+1450 per cent) and alkaline land (+52 per cent). Depletion of the SOC pool occurred in swampland (−64 per cent) both because of the decrease in the area of swampland and because of a decrease in SOC density (−34 per cent). An increase in the SOC pool occurred in alkaline land because of the increase in the area and also because of an increase in SOC density (+297 per cent), but there was little change in the SOC pool in farmland because the increase in area was largely offset by a decrease in SOC density (−14 per cent). The decrease in the STN pool was substantial (−44 per cent), with the largest contributor being the decrease in swamplands (−74 per cent)...

Land Use /Land Cover Driven Surface Energy Balance and Convective Rainfall Change in South Florida

Kandel, Hari P
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Relevância na Pesquisa
66.53%
Modification of land use/land cover in South Florida has posed a major challenge in the region’s eco-hydrology by shifting the surface-atmosphere water and energy balance. Although drainage and development in South Florida took place extensively between the mid- and late- 20th century, converting half of the original Everglades into agricultural and urban areas, urban expansion still accounts for a dominant mode of surface cover change in South Florida. Changes in surface cover directly affect the radiative, thermophysical and aerodynamic parameters which determine the absorption and partitioning of radiation into different components at the Earth surface. The alteration is responsible for changing the thermal structure of the surface and surface layer atmosphere, eventually modifying surface-induced convection. This dissertation is aimed at analyzing the extent and pattern of land cover change in South Florida and delineating the associated development of urban heat island (UHI), energy flux alteration, and convective rainfall modification using observed data, remotely sensed estimates, and modeled results. Urban land covers in South Florida are found to have increased by 10% from 1974 to 2011. Higher Landsat-derived land surface temperatures (LST) are observed in urban areas (LSTu-r =2.8°C) with satisfactory validation statistics for eastern stations (Nash-Sutcliffe coefficient =0.70 and R2 =0.79). Time series trends...

A land cover map of Latin America and the Caribbean in the framework of the SERENA project

Blanco P.D.; Colditz R.R.; Lopez Saldana G.; Hardtke L.A.; Llamas R.M.; Mari N.A.; Fischer A.; Caride C.; Acenolaza P.G.; del Valle H.F.; Lillo-Saavedra M.; Coronato F.; Opazo S.A.; Morelli F.; Anaya J.A.; Sione W.F.; Zamboni P.; Arroyo V.B.
Fonte: Universidade de Medellín Publicador: Universidade de Medellín
Tipo: Article; info:eu-repo/semantics/article
ENG
Relevância na Pesquisa
66.62%
Land cover maps at different resolutions and mapping extents contribute to modeling and support decision making processes. Because land cover affects and is affected by climate change, it is listed among the 13 terrestrial essential climate variables. This paper describes the generation of a land cover map for Latin America and the Caribbean (LAC) for the year 2008. It was developed in the framework of the project Latin American Network for Monitoring and Studying of Natural Resources (SERENA), which has been developed within the GOFC-GOLD Latin American network of remote sensing and forest fires (RedLaTIF). The SERENA land cover map for LAC integrates: 1) the local expertise of SERENA network members to generate the training and validation data, 2) a methodology for land cover mapping based on decision trees using MODIS time series, and 3) class membership estimates to account for pixel heterogeneity issues. The discrete SERENA land cover product, derived from class memberships, yields an overall accuracy of 84% and includes an additional layer representing the estimated per-pixel confidence. The study demonstrates in detail the use of class memberships to better estimate the area of scarce classes with a scattered spatial distribution. The land cover map is already available as a printed wall map and will be released in digital format in the near future. The SERENA land cover map was produced with a legend and classification strategy similar to that used by the North American Land Change Monitoring System (NALCMS) to generate a land cover map of the North American continent...

A DECISION SUPPORT TOOL FOR PREDICTING WATER QUALITY BASED ON LAND COVER

Baker, Brittney
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project
Publicado em 28/04/2011 EN_US
Relevância na Pesquisa
66.53%
Managers at Marine Corps Base Camp Lejeune must evaluate the environmental impacts of their proposed development plans. The effect of land cover changes on water quality is an important consideration for these evaluations. An interactive geospatial tool was developed in 2009. The tool allows managers to interactively select their proposed development site and input what the proposed land cover will be for the site. The tool returns the changes in average ammonium concentration in the tributary creeks. The tool incorporates water quality data collected by the DCERP project from 2008-2009 to drive the prediction model. The purpose of this project was to (1) improve usability of the tool to make it a spatial decision support system, (2) update the water quality data used to drive the statistics of the water quality prediction models, and (3) determine if using the National Land Cover Dataset (NLCD) from 2006 instead of the 2001 NLCD changes the relationship between land cover predictors and water quality response variables. Tool usability was enhanced by adding in-tool and external help menus, creating a user guide, and adding the ability to name and save outputs. The updated tool allows the user to run multiple land development scenarios for comparison without overwriting the previous results. Adding additional water quality data from 2007-2010 resulted in fewer significant water quality prediction models. The most predictive of these models was for organic nitrogen. The model...

Land Cover Change and Ecosystem Services on the North Carolina Piedmont 1985 to 2005

Donohue, Michael John
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Masters' project Formato: 4256311 bytes; application/pdf
EN_US
Relevância na Pesquisa
66.58%
Analyses of ecosystem processes are advanced through remote sensing and geostatistical modeling methods capable of capturing landscape pattern over broad spatial and temporal scales. Many ecological studies rely on land cover data classified from satellite imagery. In this, changes in land cover are often presumed to correlate with changes in ecosystem processes or services provided by ecosystems (e.g., watershed protection). Documenting changes in land cover requires that images be classified over time, often using historical images to document landscape change. But this is difficult to do for historical images because we cannot ground-truth old images, lacking actual land cover data from the past. I developed a land cover classification scheme using a classification and regression tree (CART) model generated from 2001 National Land Cover Dataset (NLCD) and Summer, Fall, and Winter triplets of Landsat 5 Thematic Mapper (TM) imagery. The model is robust to inter-annual variability in surface reflectance, and thus can be extended in time to classify land cover from images from any time, past or future. The model was used to predict land cover from 1985 to 2005, for a study region in the Piedmont of North Carolina. Temporal and spatial analyses focused on ecosystem services of carbon sequestration and biodiversity support as affected by forest fragmentation. This study offers a landscape-level identification of the relationships between spatial and temporal development patterns and the provision of ecosystem services. The project also represents the creation of a multi-annual land cover classification dataset of which few exist...

A Multi-temporal fusion-based approach for land cover mapping in support of nuclear incident response

Sah, Shagan
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
66.54%
An increasingly important application of remote sensing is to provide decision support during emergency response and disaster management efforts. Land cover maps constitute one such useful application product during disaster events; if generated rapidly after any disaster, such map products can contribute to the efficacy of the response effort. In light of recent nuclear incidents, e.g., after the earthquake/tsunami in Japan (2011), our research focuses on constructing rapid and accurate land cover maps of the impacted area in case of an accidental nuclear release. The methodology involves integration of results from two different approaches, namely coarse spatial resolution multi-temporal and fine spatial resolution imagery, to increase classification accuracy. Although advanced methods have been developed for classification using high spatial or temporal resolution imagery, only a limited amount of work has been done on fusion of these two remote sensing approaches. The presented methodology thus involves integration of classification results from two different remote sensing modalities in order to improve classification accuracy. The data used included RapidEye and MODIS scenes over the Nine Mile Point Nuclear Power Station in Oswego (New York...

A land use and land cover accuracy assessment based on Landsat 7 imagery within The Canandaigua watershed: Natural Heritage Program and The James Anderson Classification System

Money, Travis
Fonte: Rochester Instituto de Tecnologia Publicador: Rochester Instituto de Tecnologia
Tipo: Tese de Doutorado
EN_US
Relevância na Pesquisa
66.62%
Research that incorporates GIS and remotely sensed imagery has become increasingly popular and important for large-scale environmental applications, such as generating land use and land cover maps. One of the critical aspects of land cover analyses is assigning a land use and land cover classification scheme. This research evaluated two classification schemes, the 2002 Natural Heritage Classification and the 1976 James Anderson System in a land cover analysis of the Canandaigua Lake Watershed using Landsat imagery. It was hypothesized that the Landsat imagery could be used to identify unique ecological communities such as those delineated by the Natural Heritage Classification. A composite image, created from an August 15, 2003 Landsat image using bands 1, 3 and 5, was used for the fine cluster analysis, which produced 38 unique clusters. Using the Canandaigua Lake Watershed Council's land use and land cover map as a truth image (26 single NHC classes and 14 mixed NHC classes), the clustered Landsat image was used in an unsupervised classification analysis that resulted in generalized land use and land cover maps using the Natural Heritage and James Anderson Classification schemes (5 and 6 dominant land covers respectively). Because many clusters were associated with several land cover classes...