A study of habitat fragmentation in Southeastern Brazil using remote sensing and geographic information systems (GIS)
Contribuinte(s) |
Universidade Estadual Paulista (UNESP) |
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Data(s) |
20/05/2014
20/05/2014
22/10/1997
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Resumo |
The purpose of this work was to study fragmentation of forest formations (mesophytic forest, riparian woodland and savannah vegetation (cerrado)) in a 15,774-ha study area located in the Municipal District of Botucatu in Southeastern Brazil (São Paulo State). A land use and land cover map was made from a color composition of a Landsat-5 thematic mapper (TM) image. The edge effect caused by habitat fragmentation was assessed by overlaying, on a geographic information system (GIS), the land use and land cover data with the spectral ratio. The degree of habitat fragmentation was analyzed by deriving: 1. mean patch area and perimeter; 2. patch number and density; 3. perimeter-area ratio, fractal dimension (D), and shape diversity index (SI); and 4. distance between patches and dispersion index (R). In addition, the following relationships were modeled: 1. distribution of natural vegetation patch sizes; 2. perimeter-area relationship and the number and area of natural vegetation patches; 3. edge effect caused by habitat fragmentation, the values of R indicated that savannah patches (R = 0.86) were aggregated while patches of natural vegetation as a whole (R = 1.02) were randomly dispersed in the landscape. There was a high frequency of small patches in the landscape whereas large patches were rare. In the perimeter-area relationship, there was no sign of scale distinction in the patch shapes, In the patch number-landscape area relationship, D, though apparently scale-dependent, tends to be constant as area increases. This phenomenon was correlated with the tendency to reach a constant density as the working scale was increased, on the edge effect analysis, the edge-center distance was properly estimated by a model in which the edge-center distance was considered a function of the to;al patch area and the SI. (C) 1997 Elsevier B.V. B.V. |
Formato |
35-47 |
Identificador |
http://dx.doi.org/10.1016/S0378-1127(97)00072-8 Forest Ecology and Management. Amsterdam: Elsevier B.V., v. 98, n. 1, p. 35-47, 1997. 0378-1127 http://hdl.handle.net/11449/34625 10.1016/S0378-1127(97)00072-8 WOS:A1997YE09400003 |
Idioma(s) |
eng |
Publicador |
Elsevier B.V. |
Relação |
Forest Ecology and Management |
Direitos |
closedAccess |
Palavras-Chave | #landscape ecology #fragmentation of natural forest formations #edge effect #fractals #fractal dimension #fractal models #remote sensing #geographic information system #vegetation indices |
Tipo |
info:eu-repo/semantics/article |