Utilization of Compost as ameliorant in a Nickel post mining soil

Abstract

Southeast Sulawesi is one of the nickel producing regions. Nickel mining activities in addition to positive impacts can also have negative impacts such as decrease of soil and increased of accumulation of heavy metals in the soil. Therefore, couple solutions are needed to improve the quality of nickel mining soil, one of those is by providing soil amendments. The material that used in this research is compost. Compost fertilizer contains humic acid which has cation exchange ability so that it can be useful for remediating the nickel post-mining area. The research used a complete randomized design method by variating the ratio of compost to nickel post-mining soil. The method steps consisting of (1) Analysis of post-mining soil sample (2) Analysis of compost-mixed mining soil sample. The results showed that the best treatment was the 17% addition of compost to nickel post-mining sample which characterized by changes in soil characteristics, such as pH value 6.68 to 7.17 (neutral) ; C-organic content 2.01% to 3.69% (high); N-total 0.19% to 0.21% (moderate); P2O5 21.77 mg /100g to 25.03 mg/100g (moderate); K2O 15.13 to 17.77 (low); and nickel content of 1194.66 ppm to 988.86 ppm. Despite a decrease of nickel content in the soil, its level is still hazardous in term of human health.