Uso e ocupação das terras e qualidade das águas na bacia do ribeirão vai-e-vem em Ipameri (GO)

Abstract

Water is an essential prerequisite element for life and for the existence of human activity, however has been substantially polluted and contaminated by environmental liabilities from the current model of development. In the Vai-Vem Basin, located in Ipameri (GO) city, the situation of scarcity qualitative water is not unlike global context of pollution and contamination of this vital element, considering this, troubling questions arise that incite the need to develop this study that aims to diagnose the quality of the Vai-Vem Basin water, that extending the stretch of the first source until the point of capture of water, and also aims the discuss about the inseparable relationship that existing between water quality with the ownership and use of land in the watershed. The achievement of the research objectives was achieved by conducting field visits, analysis of maps for use and occupation of land in the Vai-Vem stream Basin in the period of 1973-2011, analysis of 40 water samples for the parameters turbidity, temperature, color, pH, fecal coliform and total coliform, and qualitative analysis of 44 water samples to identify the active ingredients of pesticides: atrazine, lambda- cyhalothrin, endosulfan and cyproconazole. The maps for use and occupation of land in the Vai-Vem stream Basin revealed predominance of agriculture and livestock in the basin and 56% reduction in the area covered by vegetation typical of the Cerrado in a period of 38 years. Field visits, in turn, allowed to do a list of the impacts on area researched: almost complete suppression in some places, the native vegetation that makes up the Riparian Forest which do not reach the 30 meters required by Law 12.651/2012; vegetation of the Forest riparian composed predominantly of Brachiaria decumbens; tenuous proximity of fish breeding tanks, corrals, piggery and agricultural activities with the stream; trampling by cattle around the springs; disappearance of springs; outbreaks of erosion in the pastures; intense application pesticides; thermotolerant coliform index above the NMP to water bodies of Class II in 45% of 40 water samples collected between September 2012 and August 2013; identify residues of the pesticide endosulfan-α and β -endosulfan in 2% of 44 samples collected during the period of September to December 2013. The results allow us to infer, therefore, that the use of land currently practiced in the Vai-Vem stream Basin is directly associated with the loss of water quality of this watershed.