Qualidade do solo ripário de trecho do Rio Piranhas antes da transferência de água inter-bacia do Rio São Francisco: previsão de cenários futuros

Abstract

The growing demand for water is making necessary engineering solutions to resolve the conflicts generated mainly in semi-arid regions. One of them is the elaboration of inter-basin transfer projects. There is much research on how these transfers affect the quality and quantity of water in the receiving basins, but information on how they affect the soils of these basins is incipient. The objective of this study is to evaluate the soil quality of a stretch of the Piranhas River between the Oiticica and Armando Ribeiro Gonçalves reservoirs before the arrival of water from the São Francisco River transposition project. This will be the first soil monitoring in the area that will guide a comparative analysis and construction of the scenario after the transposition in the future. For this, soil samples were collected by type of occupation both in the riverside areas and in dry stretches of the river bed. The uses were then divided between with vegetation cover and without vegetation cover. Analyzes of physical and chemical attributes of the soil were carried out: particle density, soil density, total porosity, granulometry, pH, electrical conductivity, organic matter content, carbon stock and available phosphorus. Descriptive analysis, paired t test, principal component analysis (PCA), two-way cluster and Pearson correlation were performed from the data obtained. It was determined that soils in areas without coverage suffer more erosion, are denser and have low carbon stocks. These data are important to serve as a basis for future monitoring and identify how the soil can interfere with water quality after changes in use promoted by the transfer.