A fragmentação da flora nativa como instrumento de análise da sustentabilidade ecológica de áreas protegidas Espinhaço Sul (MG)

AUTOR(ES)
DATA DE PUBLICAÇÃO

2011

RESUMO

Increasing landscape fragmentation has contributed to biodiversity loss in various Brazilian regions and might be associated with unplanned human land occupation. Conservation and survival of most biological communities are dependent upon the spatial restructuring of landscape often limited to government protected areas. This constitutes the main mechanism used by governments in preserving biodiversity, in which both ecosystems representativeness and the potential for landscape structural connectivity associated with the maintaining of biological fluxes are of fundamental importance. The area studied, located in the southernmost part of the Espinhaço Mountains in the central region of Minas Gerais state and regarded as of high biological importance, is comprised of a mosaic of conservation units of integral protection and sustainable use. In order to investigate the fragmentation dynamics of the native flora, which is constituted by seasonal semideciduous forest, rupestrian field and field, and their possible implications on the isolation of protected areas and maintenance of biological fluxes, a temporal analysis of land cover through landscape spatial indices (Fragstats) was carried out in the years of 1985 and 2008. Assessments on landscape percolation state based on percolation thresholds (Stauffer) and fragmentation (Andrén) were also made. Results show that even with the presence of mining activity, historically responsible for land occupation and economic development in the region, the natural habitat is still preserved in the area investigated and even inside the protected areas, which indicate that anthropic activities developed in the last 23 years have generally not altered native flora in quantitative terms. Results show that structural landscape fragmentation indices point to a decrease in natural habitat fragmentation as well as some connectivity strengthening among remaining forest patches which have become more elongated and closer from one another, thus occupying greater land extension with considerable portions of core areas. Correlation analysis of landscape metrics, percolation thresholds and fragmentation reveals that protected areas remain interconnected, thus allowing biological fluxes and biodiversity protection. The degree of landscape fragmentation (46%) calls for greater attention to the use of soil in the surroundings of the protected areas, notwithstanding the privileged condition regarding natural habitat. The fragmentation dynamics of the native flora in the southernmost part of the Espinhaço Mountains evidence a suitable condition for the implementation of ecological corridors to safeguard the present situation of structural connectivity detected among the protected areas.

ASSUNTO(S)

ecologia de paisagem habitat (ecologia) - fragmentação - unidades de conservação - espinhaço sul (mg).- geologia ambiental

ACESSO AO ARTIGO

Documentos Relacionados