IMPACT OF GOLD MINING ON THE MAIN PROPERTIES OF THE SOIL IN THE NORTHWESTERN OF THE DEPARTMENT OF CAUCA, COLOMBIA

Abstract

Mining activities in the Department of Cauca are associated with water and soil contamination by heavy metals, mainly cyanide and mercury, increased soil erosion, affectation of the ecosystem, and negative effects on the physical, chemical, and biological properties of the soil. The objective of this study was to determine the physical and chemical properties of the selected soils in sites exploited with mining activities, the changes were determined with respect to a non-intervened soil (High Stratum), the quality of the soil and its potential agricultural use. It was carried out in the municipality of Suárez, Department of Cauca, where artisanal gold mining is carried out. High Stratum soils show low fertility due to low contents of organic matter, nitrogen, calcium, imbalance between nutrients, which is why they have low agricultural potential, which can be increased with conservationist and controlled soil management. The microelements, although important in smaller quantities for plants, their toxicity is lethal at minimum concentrations, so it is essential that they be at the appropriate critical levels, and in these soils copper is found at toxic levels exceeding 2 mg kg-1 per day. the same as iron (critical level 25-45 mg kg-1) and Manganese in some of the soils, even in the stratum not intervened by mining. Zinc is found in quantities of 1.12 to 1.88 mg kg-1, being high and toxic values for systems for agricultural use.