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Using indicators of deforestation and land-use dynamics to support conservation strategies: A case study of central Rondonia, Brazil

FERRAZ, Silvio Frosini de Barros; VETTORAZZI, Carlos Alberto; THEOBALD, David M.
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
66.16%
In Rondonia State, Brazil, settlement processes have cleared 68,000 km 2 of tropical forests since the 1970s. The intensity of deforestation has differed by region depending on driving factors like roads and economic activities. Different histories of land-use activities and rates of change have resulted in mosaics of forest patches embedded in an agricultural matrix. Yet, most assessments of deforestation and its effects on vegetation, soil and water typically focus on landscape patterns of current conditions, yet historical deforestation dynamics can influence current conditions strongly. Here, we develop and describe the use of four land-use dynamic indicators to capture historical land-use changes of catchments and to measure the rate of deforestation (annual deforestation rate), forest regeneration level (secondary forest mean proportion), time since disturbance (mean time since deforestation) and deforestation profile (deforestation profile curvature). We used the proposed indices to analyze a watershed located in central Rondonia. Landsat TM and ETM+ images were used to produce historical land-use maps of the last 18 years, each even year from 1984 to 2002 for 20 catchments. We found that the land-use dynamics indicators are able to distinguish catchments with different land-use change profiles. Four categories of historical land-use were identified: old and dominant pasture cover on small properties...

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
66.19%
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
66.17%
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
66.17%
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...

Land use/ land cover change and its impact on soil erosion process in Begnas Tal Rupa Tal watershed using geospatial tools, Kaski district, Nepal

Koirala, Saroj
Fonte: Universidade Nova de Lisboa Publicador: Universidade Nova de Lisboa
Tipo: Dissertação de Mestrado
Publicado em 02/03/2010 ENG
Relevância na Pesquisa
66.2%
Dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Science in Geospatial Technologies; The spatial-temporal analysis of changes in land use/land cover between 1988 and 1999 at Begnas Tal Rupa Tal Watershed, covering an area of about 50.94 km² in Kaski District, Nepal, reveals the changing scenario of land use/land cover and their consequent effect on soil erosion. The geo-spatial analysis of database generated from the satellite images, ancillary database and socio-economic information critical/vulnerable areas of land degradation are identified. Visual interpretation technique is carried out for land use/land cover by comparing satellite images of Landsat TM from 1988 to 1999 using GIS tools. Datasets of moderate spatial resolution (Landsat TM) have been processed. The geo-spatial analysis results show an increase in major land use/land cover such as agricultural land, dense mixed forest and settlement whereas there is decrease in barren land and open forest. The main land cover such as open forest and barren land are converted both into agricultural land and settlement. This change in land use indicates that the mountain land use is changing rapidly in the Himalayan region. It has not only disrupted ecological balance of the watershed but also reduced ground water recharge...

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
66.22%
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...

Biofuels and Climate Change Mitigation : A CGE Analysis Incorporating Land-Use Change

Timilsina, Govinda R.; Mevel, Simon
Fonte: Banco Mundial Publicador: Banco Mundial
Relevância na Pesquisa
66.21%
The question of whether biofuels help mitigate climate change has attracted much debate in the literature. Using a global computable general equilibrium model that explicitly represents land-use change impacts due to the expansion of biofuels, this study attempts to shed some light on this question. The study shows that if biofuel mandates and targets currently announced by more than 40 countries around the world are implemented by 2020 using crop feedstocks, and if both forests and pasture lands are used to meet the new land demands for biofuel expansion, this would cause a net increase of greenhouse gas emissions released to the atmosphere until 2043, since the cumulative greenhouse gas emissions released through land-use change would exceed the reduction of emissions due to replacement of gasoline and diesel until then. However, if the use of forest lands is avoided by channeling only pasture lands to meet the demand for new lands, a net increase of cumulative greenhouse gas emissions would occur but would cease by 2021...

Evaluation of the Impact of Payments for Environmental Services on Land Use Change in Quindío, Colombia

Pagiola, Stefano; Rios, Ana R.
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
66.22%
The growing use of Payments for Environmental Services (PES) for conservation has fostered a debate on its effectiveness, but the few efforts to date to assess the impact of PES programs have been hampered by lack of data, leading to very divergent results. This paper uses data from a PES mechanism implemented in Quindío, Colombia, to examine the impact of PES on land use change. Alone among all early PES initiatives, the Silvopastoral Project included a control group of nonparticipants, whose land use changes were monitored throughout the project period, as well as detailed baseline data on both PES recipients and control group members. By comparing the land use changes undertaken by PES recipients to those undertaken by control group members, we can distinguish the impact of PES from that of other factors. The results show that payments had a positive and highly significant impact on land use change, under a variety of model formulations. PES recipients converted over 40 percent of their farms to environmentally-friendly land uses over 4 years...

Evaluation of the Permanence of Land Use Change Induced by Payments for Environmental Services in Quindío, Colombia

Pagiola, Stefano; Honey-Rosés, Jordi; Freire-González, Jaume
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
EN_US
Relevância na Pesquisa
66.19%
The effectiveness of conservation interventions such as Payments for Environmental Services (PES) is often evaluated, if it is evaluated at all, only at the completion of the intervention. Since gains achieved by the intervention may be lost after it ends, even apparently successful interventions may not result in long-term conservation benefits, a problem known as that of permanence. This paper uses a unique dataset to examine the permanence of land use change induced by a short-term PES program implemented in Quindío, Colombia, between 2003 and 2008. This the first PES program to have a control group for comparison. Under this program, PES had been found to have a positive and highly significant impact on land use. To assess the long-term permanence of these changes, both PES recipients and control households were re-surveyed in 2011, four years after the last payment was made. We find that the land use changes that had been induced by PES were broadly sustained in intervening years, with minor differences across specific practices and sub-groups of participants. The patterns of change in the period after the PES program was completed also help better understand the reasons for the program s success. These results suggest that...

Land use change: implications for Australian Capital Territory Water use

Newham, L T H; Buller, C D; Barnett, P; Field, J B
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Working/Technical Paper Formato: 26855 bytes; application/pdf
EN_AU
Relevância na Pesquisa
66.18%
Managing water resources to ensure environmental values are maintained, whilst allowing for continued economic development is a major challenge facing many areas including the Australian Capital Territory (ACT). This paper reports on a GIS based investigation of the implications of land use change on ACT water use. The paper describes a suite of tools that are collectively termed PLUCA (Platform for Land use Change Assessment).

Areas with the potential for land use change were identified through land capability assessment and by investigation of the suitability of land for development of alternate industries. Spatial data including slope, aspect, a wetness index, climatic surfaces, geology and consideration of the minimum viable scale of industry were analysed in the study.

A coarse land use class – water use relationship estimated for the ACT was used to determine the maximum potential water use resulting from land use change. Three scenarios, based on different levels of land use change were constructed to simulate high, medium and low levels of potential landuse change in the ACT. The estimated reduction in streamflow for the maximum development scenario, was around 6.8% of the average annual runoff from the ACT. This scenario represented modification of only 3.9% of the total land area.

This study demonstrates the potential for the use of GIS in the optimisation of landuse from biophysical characteristics. The implications of such changes should they occur were calculated through investigation of the annual average reduction in streamflow. The study demonstrates the use of GIS techniques in quantifying interactions at appropriate scales for decision making. The development of improved decision support tools is also outlined.

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A comparison of combinatory methods and GIS based MOLA (IDRISI®) for solving multi-objective land use assessment and allocation problems

Sharma, Sunil Kumar
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Thesis (PhD)
EN
Relevância na Pesquisa
66.21%
The aim of this study was to provide an informed choice among two combinatory methods and GIS based MOLA module in IDRISI® by comparing their performance in solving a hypothetical Multi-Objective Land use Assessment and Allocation (MOLAA)problem. Among the combinatory methods, Simulated Annealing and Tabu Search algorithms were chosen for study. The application of Simulated Annealing has already been demonstrated in solving a MOLAA problem but Tabu Search has not been used to a MOLAA problem before. The Kioloa Region of New South Wales, Australia was chosen for designing a hypothetical MOLAA problem due to availability and access to the digital datasets at the Australian National University. The MOLAA problem was formulated for accomplishing six land use objectives by allocating the area to four land use types, that is, conservation, agriculture, forestry and development, using altogether 1 7 criteria, including 16 factors and one constraint. The criteria maps were classified in ordinal, continuous and fuzzy scale and combined by using Weighted Linear Combination to produce land use suitability models for each land use type. The ordinal and continuous land use suitability models were used in solving the problem by applying the MOLA module. In order to apply the combinatory methods...

Development, land-use change and rural resettlement capacity: a case study of the Three Gorges Project, China

Tan, Y.; Bryan, B.; Hugo, G.
Fonte: Carfax Publishing Publicador: Carfax Publishing
Tipo: Artigo de Revista Científica
Publicado em //2005 EN
Relevância na Pesquisa
66.18%
Resettlement of people displaced by dam projects is an important development issue. Land lost due to the Three Gorges reservoir inundation and the adjustment of land-use policy in China resulted in land-use changes, and impacted on the human carrying capacity of the land and the land availability for resettlement. The Chinese government has implemented a ‘development-oriented resettlement’ policy and a ‘near resettlement’ approach to relocating rural dwellers affected by the Three Gorges Project (TGP). Based on recent land-use survey and population data of the case study area and using GIS-based multi-criteria analysis in land-use planning, this study analyses the characteristics and changes of land use in both the inundation and resettlement areas. Undeveloped land is scarce in both areas. The non-flooded cultivated land is distributed mainly on steep slopes (over 25 degrees). There is a discrepancy between the amount of land required by those being resettled and what is available in the designated resettlement communities. This study suggests that resettlement should consider the human carrying capacity of the land and, from a community standpoint, sheds light on the interplay between land-use planning and resettlement, and provides constructive suggestions for TGP resettlement strategies.; Yan Tan...

Geographic Patterns of Land Use and Land Intensity in the Brazilian Amazon

Chomitz, Kenneth M.; Thomas, Timothy S.
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
66.2%
Using census data from the Censo Agropecuario 1995-96, the authors map indicators of current land use, and agricultural productivity across Brazil's Legal Amazon, These data permit geographical resolution about ten times finer than afforded by "municipio" data, used in previous studies. The authors focus on the extent, and productivity of pasture, the dominant land use in Amazonia today. Simple tabulations suggest that most agricultural land in Amazonia yields little private economic value. Nearly ninety percent of agricultural land is either devoted to pasture, or has been out of use for more than four years. About forty percent of the currently used pastureland, has a stocking ratio of less that 0.5 cattle per hectare. Tabulations also show a skewed distribution of land ownership: almost half of Amazonian farmland is located in the one percent of properties that contain more than two thousand hectares. Multivariate analyses relate forest conversion, and pasture productivity to precipitation, soil quality...

The Effect of Climate and Technological Uncertainty in Crop Yields on the Optimal Path of global land use

Cai, Yongyang; Steinbuks, Jevgenijs; Elliott, Joshua; Hertel, Thomas W.
Fonte: World Bank Group, Washington, DC Publicador: World Bank Group, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
66.23%
The pattern of global land use has important implications for the world's food and timber supplies, bioenergy, biodiversity and other eco-system services. However, the productivity of this resource is critically dependent on the world's climate, as well as investments in, and dissemination of improved technology. This creates massive uncertainty about future land use requirements which compound the challenge faced by individual investors and governments seeking to make long term, sometimes irreversible investments in land conversion and land use. This study assesses how uncertainties associated with underlying biophysical processes and technological change in agriculture affect the optimal profile of land use over the next century, taking into account the potential irreversibility in these decisions. A novel dynamic stochastic model of global land use is developed, in which the societal objective function being maximized places value on food production, liquid fuels (including bio-fuels), timber production...

Confronting the Food-Energy-Environment Trilemma : Global Land Use in the Long Run

Steinbuks, Jevgenijs; Hertel, Thomas W.
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Policy Research Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
66.22%
Economic, agronomic, and biophysical drivers affect global land use, so all three influences need to be considered in evaluating economically optimal allocations of the world's land resources. A dynamic, forward-looking optimization framework applied over the course of the coming century shows that although some deforestation is optimal in the near term, in the absence of climate change regulation, the desirability of further deforestation is eliminated by mid-century. Although adverse productivity shocks from climate change have a modest effect on global land use, such shocks combined with rapid growth in energy prices lead to significant deforestation and higher greenhouse gas emissions than in the baseline. Imposition of a global greenhouse gas emissions constraint further heightens the competition for land, as fertilizer use declines and land-based mitigation strategies expand. However, anticipation of the constraint largely dilutes its environmental effectiveness, as deforestation accelerates prior to imposition of the target.

Projected 1980 land use; Central Florida Planning Region

Central Florida Regional Planning Council
Fonte: The Council ( Bartow Fla. ) Publicador: The Council ( Bartow Fla. )
Tipo: cartographic Formato: 1 map : photocopy ; 90 x 84 cm. folded to 92 x 48 cm.
Publicado em //1977 ENGLISH
Relevância na Pesquisa
66.21%
Blue line print.; "Draft" is stamped on legend area.; "May, 1977."; Shows change in land use 1976-1980 in Polk, Hardee, DeSoto, Highlands and Okeechobee counties.; Includes location maps.; (Funding) Funded in part by the University of Florida, the Florida Heritage Project of the State University Libraries of Florida, the Institute for Museum and Library Services, and the U.S. Department of Education's TICFIA granting program.; (Statement of Responsibility) Central Florida Regional Planning Council.

The impact of land use change and check-dams on catchment sediment yield

Boix-Fayos, Carolina; Vente, Joris de; Martínez-Mena García, M. Dolores; González Barberá, Gonzalo; Castillo Sánchez, Victor Manuel
Fonte: John Wiley & Sons Publicador: John Wiley & Sons
Tipo: Artículo Formato: 579917 bytes; image/jpeg
ENG
Relevância na Pesquisa
66.18%
Extensive land use changes have occurred in many areas of SE Spain as a result of reforestation and the abandonment of agricultural activities. Parallel to this the Spanish Administration spends large funds on hydrological control works to reduce erosion and sediment transport. However, it remains untested how these large land use changes affect the erosion processes at the catchment scale and if the hydrological control works efficiently reduce sediment export. A combination of field work, mapping and modelling was used to test the influence of land use scenarios with and without sediment control structures (check-dams) on sediment yield at the catchment scale. The study catchment is located in SE Spain and suffered important land use changes, increasing the forest cover 3-fold and decreasing the agricultural land 2·5-fold from 1956 to 1997. In addition 58 check-dams were constructed in the catchment in the 1970s accompanying reforestation works. The erosion model WATEM-SEDEM was applied using six land use scenarios: land use in 1956, 1981 and 1997, each with and without check-dams. Calibration of the model provided a model efficiency of 0·84 for absolute sediment yield. Model application showed that in a scenario without check dams...

Modelling interactions and feedback mechanisms in land use systems

Chen, Yang; Ligtenberg, Arend; Bakker, Martha; Bregt, Arnold
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Conferência ou Objeto de Conferência Formato: application/pdf
Publicado em //2014 ENG
Relevância na Pesquisa
66.17%
Land use change (LUC) is often a complex process. In such a process land use systems can show non-linear behaviours caused by mechanisms such as interactions between agents and feedbacks from higher system level. Land use systems might be very sensitive to such non-linearity, for instance in the form of tipping points, which lead them to a different land use regime. Many models deal with the causes and consequences of LUC but few focus on the non-linear process in land use systems. Thus there is a need for an explicit treatment of interactions and feedback mechanisms in LUC models to better understand the behaviour of land use systems. Two primary mechanisms are implemented with an agent-based model (ABM) to capture 1) the social interaction between land use decision makers (farmers) and 2) the positive feedback mechanism in agricultural production, with each applied to a case study showing how such mechanism can give rise to non-linear changes in land use systems. Due to a lack of focus on feedbacks in LUC-ABMs, we propose a framework to approach feedback mechanisms in land use systems in a structured way.

Historical land-use legacy and Cortaderia selloana invasion in the Mediterranean region

Domènech i Masons, Roser; Pino i Vilalta, Joan
Fonte: Universidade Autônoma de Barcelona Publicador: Universidade Autônoma de Barcelona
Tipo: Artigo de Revista Científica Formato: application/pdf
Publicado em //2005 ENG
Relevância na Pesquisa
66.18%
Two major components of global change: land-use changes and intentional or accidental species introduction are threatening the conservation of native species worldwide. In particular, Mediterranean coastal areas are highly susceptible to the invasion of alien species and they also have experienced major changes in land use such as agricultural abandonment and urbanization. However, there has been little research done which quantitatively links biological invasions and the components of land-use changes (i.e. number, trajectory and direction of the changes). We analysed the current distribution and abundance of Cortaderia selloana (Schultes et Schultes fil.) Asch. et Graebner, an alien ornamental species, in 332 fields in Aiguamolls de l'Empordà (Catalonia, NE Spain) and related the patterns of invasion to spatiotemporal data on land-use changes from 1956 to 2003. Our aim was to determine which land uses had been more susceptible to C. selloana invasion during the last 5 years and to find out which components of land-use changes triggered invasion. We found that 22.30% of the fields are currently invaded. In the last 5 years, fields have triplicated the total density of C. selloana. The presence of C. selloana decreases with the distance from urban areas. Invasion is over-represented in pastures and old-fields...

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
66.2%
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...