Restoration of soil chemical and mercury content in former mining land with the application of biochar, manure and clay for the sunflower growth and production

Abstract The former gold mining land is a that has deficient fertility level and contained heavy metals such as mercury (Hg). purpose of this research to study the role biochar, manure, clay sunflowers in reducing (Hg) restoration land. researcher used random design method with groups 3 treatments repetitions. treatment consists 0 ton/ha, 10 20 ton/ha clay. result shows effect reviving chemical properties soil able levels increasing production sunflowers. best happened dose tons/ha, value pH 6.12, P-available 30,89 ppm, C-organic 2,457%, N-total 0,1459%, CEC 23.87 me.100g-1, K-dd 0,1309 Mg-dd 0,254 Na-dd 0,116 Hg 19,748 sunflower 4,14 g/100 seeds accumulate trunk 15,05 ppm 6,69 root.