Reclamation of ex-nickel mining soil using organic plus fertilizer to support corn cultivation in Southeast Sulawesi

In addition to providing incomes for the country, mining activities can also cause land damage resulting in a decrease in soil function as a medium for growing plants. The study aim to analyse the growth and production of corn on ex-nickel mining soils that had been remediated using cover crops and rhizobacteria for five years (2013-2018). The research has arranged in a randomized block design (RBD) with the treatment of organic fertilizer enriched with rhizobacteria of Bacillus sp and Pseudomonas sp (organic plus fertilizer), consisting of 6 levels, namely control without organic plus fertilizer (B0), 1 ton ha^-1 (B1), 2 tons ha^-1 (B2), 3 tons ha^-1 (B3), 4 tons ha^-1 (B4), and 5 tons ha^-1 (B5). Each treatment was repeated three times so that there were 18 experimental units. The observed variables were plant height, stem diameter, leaf area, the weight of corn kernels per fruit, and weight of dried kernels per hectare. The results show that the application of organic plus fertilizer on the ex- nickel mining soils effectively increased the growth and production of corn.