Diagnosis of quality of groundwater and elaboration of land use in the region of Irecê-BA

Abstract

The study area is located in the micro region of Irecê, located in the north central part of Bahia state, including a pilot area of the Salitre karst aquifer bounded in the municipalities of Irecê and Lapão. Makes a total area of approximately 250km² and is composed of carbonate rocks of Neoproterozoic age Salitre karst aquifer Formation. This geological unit is the karst aquifer saltpeter, which is the main source of water for irrigation purpose. It was performed a risk assessment of soil salinization and sodification through a study of quality of groundwater used for irrigation, with analysis of physico-chemical elements 40 and 32 semi-volatile compounds. Particle size analysis was also performed and metals in the soil and prepare the Map Land Use of Soil and Slope Map of the area to assess the most favorable areas for agriculture. The analysis of the water used for irrigation purpose has shown that the two campaigns made, 89% of groundwater analyzed were classified as C₃S₁ and can normally be used for irrigation projects and only 11% of samples were classified as C₄S₁, which waters are not to be used for irrigation, because of the danger of salinization of soil.