Análise espacial de remanescentes florestais como subsídio para o estabelecimento de unidades de conservação
Abstract
The current state of fragmentation of remaining natural vegetation in São Paulo generates the need for urgent action for conservation. The prioritization of areas is the first step toward developing strategies for biodiversity conservation because it allows the targeting of efforts and resources to subsidize the maintenance and development of public policies on land use. In this sense, this study aimed to diagnose the distribution of fragments of natural vegetation in the municipality of Sorocaba / SP and identify priority areas for conservation through the use of landscape metrics in order to support the creation of protected areas (PA). The remnants of natural vegetation s map was elaborate (1:2.000) through vectorization screen using aerial photographs with scale 1:20.000 of 2006. The maps of hydrography and contour lines were used in the preparation of the Permanent Preservation Areas map (PPA). The following metrics were used for the map of priority areas for conservation: Area (hectares) PROX (connectivity between fragments) and SHAPE (relationship between perimeter and area). The metrics were valued and assigned to a weight to each of them. The results showed a high degree of habitat fragmentation, with only 16.68% of municipal land with forest cover and 62% of fragments smaller than 1ha, and the largest fragment showing approximately 300 ha. 19% of the territory is PPA, and this area has only 45% forest cover (50% of the total forest cover of the municipality). The restoration of all PPA represents an increase of 11% of forest cover in the entire territory, from 16,68% to 28% and also the appearance of fragments larger than 3.000 ha. The areas with the highest priority for conservation are located in the southeast region of the municipality, where most of rural areas still exist. Another high priority area appeared on the waterfront Pirajibú. Except of the public area called Mario Covas Park, the other fragments with very high priority areas are on private properties, which should lead to an incentive for the creation of PRNP and AMPA. The present situation of the scarcity of forest remnants of the city generates a demand for immediate action for conservation and ecological restoration. The strategies should involve stopping and possibly reversing the process of degradation of natural ecosystems. Thus, the municipality must ensure the preservation of forest remnants through public or private PA, and must implement an ecological restoration program involving various stakeholders such as schools, industries, NGOs and other sectors. Whereas the expansion of the city is an ongoing process, territorial planning should be done to reconcile the demands for infrastructure with the conservation of forest remnants. Plans for urban and industrial expansion should be integrated into the plans of conservation and restoration of natural areas, as provided in Municipal Environmental Policy.