The expansion of the irrigated area, the temporal and spatial poor distribution, as well as the misuse of water and land are causes of serious water problems in river basins. Given the relevance of knowledge of the hydrological behavior and coverage of land use and the absence of the Rio Pardo River basin Committee, this study aimed to evaluate the hydrological behavior of the Pardo River basin, with Based on estimates of the consuntive uses of water and the influence of vegetation cover on the minimum, medium and maximum flows of the river. The spatial distribution of the annual average rainfall was analyzed; Of the annual average reference evapotranspiration; of minimum flows, long-term averages, and maximum rates associated with the permanence of 90; Of the average long-term specific flows; and the coefficient of outlet in 10 fluvimetric stations located in the Pardo River basin. For the estimation of the withdrawal flows and consumed by the irrigation and by the human urban, rural and animal human supplies, data obtained from IBGE and in the FAO Bulletin 24 were used, in the case of data related to the crops for the calculation regarding irrigation. For the study of land use and cover along the basin, six Landsat satellite images of the year 2011 were used, with spatial resolution of 30 meters, and were treated using the ArcGIS software. The quantitative analysis of the data was performed using the simple linear Regression statistical procedure, adopting as dependent variable the flows and independent variables the percentage of forest in the drainage area of each Fluvimetric station and multiple linear regression; Adopting as dependent variable the maximum flow and independent variables the drainage area and the forested area of each sub-basin. The results showed that the average annual rainfall and the long-lasting mean specific flows behaved similarly, presenting higher values closest to the mouth, decreasing in the central region of the basin; The maximum, minimum and average long-term flows increased towards the mouth; In general, the total consumed by the four user segments was very expressive in relation to the average long-term flow, with irrigation being the segment that consumes the most water in the basin, varying between 95.8 and 99.1 of the total consumed; The flow of withdrawal by irrigation reached 87.2 of the Q7, 10 observed, 48.6 of Q7, 10 natural and 92.6 of Q90 at Inhobim station; The areas occupied by pasture represent the predominant land use category in the basin; And, in general, the quantitative analysis was able to define the relationship between the forest percentage and the hydrological behavior, with the percentage of forest being the most influential in the flow of rivers.
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