Mírian Maria de Paula
Abstract:
This research was based on the perspective of understanding the interference of land use on the physical and chemical parameters of water quality indicators of the Ribeirão das Pedras Basin - Quirinópolis/GO, the main source of supply for the urban population. This area is occupied by intensive grazing of beef cattle and milk, presenting a picture of environmental degradation common to the implementation of the livestock system. The objective of the research was to evaluate how land use interferes with water quality indicator parameters from the integrated use of geotechnologies and physicochemical analyzes of water. The parameters evaluated in situ using the Oakton PCD650 multiparameter equipment were Temperature (T), Hydrogen Potential (pH), Electrical Conductivity (EC), Electrical Resistivity (RE), Salinity (SAL) and Total Dissolved Solids (TDS), following the methods described in APHA. Laboratory analyzes of suspended sediment concentration (CSS) data were performed. The collections were performed from October 2009 to September 2010, in fourteen sampling points. The creation of a geographic database in the SPRING application that, using topographic charts, LANDSAT-5 TM satellite images and GPS data, enabled the elaboration of thematic maps of land use, vegetation, geomorphology, geology, soils and slope of the relief. From the result of these data, it was identified that predominate areas occupied by the Pastures (59.89%), Forest/Cerrado (22.30%) and Exposed Soil (7.98%) classes. It was also observed the low expressiveness of the Culture class in the area, where it is represented with only 2.47%. Regarding geomorphology, the area is part of the geomorphological unit called Northern Plateau of the Paraná Sedimentary Basin, where the highest levels range from 600 to 900 meters in altitude. As for slope, most of the basin land (88%) is in the categories of up to 12%, which represent frailty ranging from very weak to weak. Regarding the limnological characteristics, the Temperature showed an average of 24ºC, with a maximum, 34.9ºC, recorded in P7, in November 2009 and a minimum, 16.2ºC, recorded in P1, in August 2010, thus demonstrating relationship with the air temperature in the period; pH values were close to neutrality in almost all analyzed points, only in P1 they were more acidic, a fact explained by the presence of basaltic outcrop and intense anthropization of the area; P1 also presented higher values of electrical resistivity, 895.00MΩ.cm, explained by the lower presence of dissolved solids; The most significant differences in CE, Salinity and TDS occurred in P2 during the rainy season and CSS analyzes presented the highest values at Points 5, 8 and 1, respectively, facts explained by the practices developed near the collection points. Given the analysis, it was found that the forms of occupation and use of land are interference factors in the limnological variables of the study area. Despite presenting adequate conditions for use, according to the data evaluated in relation to Resolution CONAMA 357/2005, the water of the Basin must be preserved 16 through soil conservation practices, which will bring security of supply to the population.
