Land use changes in watersheds and impacts on natural resources and human population

Abstract

The space appropriation by man and his activities in rural and urban areas promotes changes in land use and changes in the hydrological cycle, resulting in reduced rates of infiltration and increased runoff. As a consequence, flood episodes, erosion and silting rates are increased, especially when soil cover is altered or suppressed. The Avaré and Ourinhos municipalities, founded at the beginning of the 20th century, suffered considerable changes in the vegetation cover of their territories throughout their histories, initially harboring the coffee cycle and, currently, sugar cane, corn, soybeans and pastures. Both have had steady increase of their populations, which today are essentially in urban area. This process contributed to the fact that its watersheds were modified mainly in the urbanized areas where these have been continuous and widely waterproofed. In this context, the objective of this project is to analyze the relationship between the transformations in land use that occurred in the last decades in Córrego da Onça (Avaré) and Água da Veada (Ourinhos) watersheds, the erosion and silting processes and floods at the studied areas in the years 1972, 2004 and 2016, as well as the impacts on the resident population in these locals. The public managers perception and the resident population in the areas about the causes and consequences of the processes and problems related to the subject matter will also be evaluated. The results should serve as a subsidy to the planning, management and environmental management of the watersheds studied. It is also hoped that the methodology can be replicated in other areas with similar characteristics and that may help the solution and prevention of water crises that has increased due to the lack of knowledge and models systems of nature and the lack of consideration of impacts that the unordered decisions bring about natural resources, especially water, soil, vegetation, wildlife and regional mesoclimes. (AU)