Recursos hídricos em veredas do bioma cerrado no estado de Goiás

• Autor(a) principal: Pereira, Sidney
• Data de Publicação: 2010
• Tipo de documento: Tese
• Idioma: por
• Título da fonte: Repositório Institucional da UFG
• Texto Completo: http://repositorio.bc.ufg.br/tede/handle/tede/9822
• topic: Monitoramento ambiental; Lençol freático; Quantidade de água; Vazão; Índice de qualidade de água; Environmental monitoring; Water table level; Water amount; Flow; Water quality index; ENGENHARIA DE AGUA E SOLO::CONSERVACAO DE SOLO E AGUA

Among the several vegetation types of the Cerrado (savanna) biome, there are the veredas (a type of waterway or water source), humid subsystem that participate in the control of the flow water table, playing key role in the hydrological balance of water courses. Such environments, however, are sensitive to environmental change, low regenerative capacity and are being degraded mainly due to agricultural activities. Although the quality of water in waters resources is the subject of studies, few refer specifically to the veredas of the Cerrado and rare in relation to the amount of flowed water. In this sense, this study aims to characterize quantitatively and qualitatively the waters resources, in conserved and anthropic veredas of the Cerrado biome, through the evaluation of the consequences of these interferences in these environments. In this context, it was looked for to monitor: the behavior of the water table level of the selected veredas; the flow of the course of these drainage, and; the quality of the water through their aspects physical, chemical, microbiological and agricultural chemicals, that composed WQI-CCME (water quality index developed by Canadian Council of the Ministry of the Environment) with reference to these variables values predetermined by the Resolution Conama n.º 357/05. Six veredas were selected, divided in two suits, called "suit 1" (T1, in the city of Bela Vista de Goiás/GO) and “suit 2” (T2, in the city of Silvânia/GO). Each suit contains a vereda inserted in crop region (VL) and another inserted in area of grassland (VP) also conserved vereda (VC). The results showed that vereda with disturbed grassland (T2VP), presented larger variation in the water table level, probably due to less water infiltration into the soil, its surroundings, due to existence of very degraded pastures. The abrupt variation of the flow is related, among other factors, with the topography of the land and the use of anthropic its surroundings. In the determination of WQI-CCME, the variables "pH", "soluble iron" and "dissolved oxygen" were the most restrictive for the veredas of T1. In T2 were more restrictive the variables pH and dissolved oxygen. The effect of the seasonality was not observed on the value of WQI-CCME. The "dissolved oxygen" is not an efficient variable to determine the quality of waters in veredas, as the water emerges from underground, that naturally have low concentrations of dissolved oxygen. In case they were just adopted only the references values of the Resolution Conama n.º 357/05, the veredas would belong to Classes 3 and 4, what doesn't correspond to the definitions of this resolution for these water resources, because the veredas present water of good quality and with several applications beyond those provided in these classes.