Zoneamento ambiental da bacia hidrográfica do médio Mogi-Guaçu superior

Abstract

The sustainable management of the ecosystems became an indispensable tool for the conservation and use of the natural resources and for the human well-being. The watershed river as a landscape unit presents a space arrangement of different types of natural ecosystems and of differentiated land uses that can result in risks or threats to the integrity and the ecological sustainability of the environmental systems. The landscape dynamics of a watershed river is related to the knowledge of the modifications of the land uses and of their relationships with physical, biological, socioeconomic and political factors, and represents also an essential condition in the strategies definition for the environmental planning. This work intends the Environmental Zoning of Medium Mogi-Guaçu River Watershed proposition in the perspective to a environmental diagnose occupation conditions due to the local development actions, along the time, providing subsidies for the environmental mangement and planning in the perspective of the ecological sustainability. The characterization and analysis of the watershed landscape structure and of the municipal districts that integrate the landscape unit, as well as the conceptual proposal of environmental zoning was elaborated using a System of Geographical Information (SIGs), in way to organize a georeferenced database that make possible the administration and analysis of the integrated data. For the classification and identification of the land uses and occupation were used LandSat 5-TM bands (3,4 and 5) images, dated of July of 1984, August of 1990, June of 2000 and August of 2007; planialtimetric maps (1:50.000); geology and soil maps, besides sócio-economic data. Thematic letters related to the following landscape structural elements were elaborated: Road net, pedology, hipsometriy, hydrography, land cover and land use and occupation, Index of Urbanity, Index of Environmental Quality and a conceptual Permanent Preservation Area, with base in GIS (Idrisi V.15 and MapInfo8.5). With the LandSat images classification was possible to obtain the land use dynamics in a period of 23 years (1984 to 2007), as well as identified the watershed land use condition and occupation for 2007. The results demonstrate that local landscape was loosing the naturalness in function of agriculture and urbanization processes. The remaining fragments of natural vegetation related to different types of land cover, evidence a landscape scenery quite fragmented because of agricultural expansion and of the development regional. These results allowed the elaboration of a Environmental Zoning conceptual proposal for the watershed. Were proposed eight Zones involving special areas of interest for conservation, as well as management and conservation strategies for the flood plain of the medium Mogi-Guaçu river. The results evidence the need of an appropriate management of the productive current areas, as well as the management of agricultural and industrial expansion. They still evidence the need to promote dialogues and actions capable to establish a swinging among the support capacity of the natural systems in detriment to the maintenance of the global production of goods in the perspective of the watershed ecological sustainability.