Uso da terra nas bacias hidrográficas do Rio do Peixe (SC) e do Rio Pelotas (RS/SC) e sua influência na limnologia do reservatório da UHE-ITÁ (RS/SC)

Abstract

The conservation of the hydric resources is a growing increasing, since only small portion is available for human consumption and the activities. The population growth and jointly with new technology development intensifies human activities in the terrestrial and aquatic way, causing deterioration in the water quality. This way, they stand out the studies that aim at the integration of the terrestrial and aquatic ways driving the environment the protection and conservation. In this sense, this work sought to identify the relationships among the limnology characteristics of the UHE-Itá (RS/SC) reservoir, the land use and relief watershed of the Peixe and Pelotas rivers, seeking integrated approach of the aquatic and terrestrial ecosystems in the dynamics of the environmental quality. Through the analysis of the cartographic products one verified that the watersheds of the Peixe and Pelotas rivers don't present expressive differences as for the land, prevailing the field, the agriculture and the forest, respectively. In relation to the permanent preservation areas surre the reservoirs were surrounding observed that these are not respected. Already in the geomorphology, the watersheds of the Peixe river presents ¾ of the area practically with strong relief dissection, while in the watersheds Pelotas river 1/3 of the area just comes strongly dissected. As for the liminology characteristics the most expressive differences happened in the variables: total of sediments in suspension, depth of the disk of Secchi and color of the water. Starting from these verifications it can be inferred that the main alterations found for the limnology variables are more related with the volume of antecedent precipitations, the current use in the collection period and predominant geomorphology in the reception areas. The largest alterations in the limnology characteristics happened in collection September, linking with the largest rain volume, the land use destined to the agriculture (especially exposed soil) and the influence of the strong dissection of the relief, mainly in the watershed of the river of the Peixe