Efecto de la adición de enmiendas en la inmovilización de metales pesados en suelos mineros del sur de Bolívar, Colombia

Soil degradation as a consequence of informal mining is evident in some areas of the department of Bolivar in Colombia. Therefore, it is necessary to look for strategies that minimize the impact of these pollutants on agricultural crops. The aim of this study was to evaluate the immobilization of heavy metals (mercury, lead, cadmium, and arsenic) in soils contaminated by mining activities from southern Bolivar, through the use of amendments (biochar: D1 = 0.5 %, D2 = 2 %, D3 = 4 %; vermicomposting: D1 = 5 %, D2 = 10 %, D3 = 15 %, and lime: D1 = 0.5 %, D2 = 1 %, D3 = 2 %). The treatments were performed in triplicate using a randomized complete block design with two factors (amendment and dose) of 3 × 3 for a total of 30 experimental units, including the control. Soil characterization was also carried out. The results showed that metals such as lead, cadmium, and mercury are highly retained by the soil with vermicompost and lime amendments. The most effective amendment to retain arsenic in the soil was lime. In general, soils amended with vermicompost, biochar and lime showed good behavior for the bioavailability of heavy metals (Pb, Cd, As, and Hg), favoring the decrease in plant toxicity.