Effects of Biochar + Calcium-magnesium Fertilizer Made of Soda Waste on Cd-polluted Soil, Yield and Quality of Peanut (Arachis hypogaea L.)

【Objective】The study was conducted to verify the improvement effects of biochar(B)+calcium-magnesium fertilizer(C) made of soda waste on soil contaminated by heavy-metal Cd.【Method】On the bases of conventional fertilization(NPK), the treatments of NPK(CK), NPK+20 t/hm2 B, NPK+3 t/hm2 C and NPK+20 t/hm2 B+3 t/hm2 C were made in the field plot experiment of peanut (Arachis hypogaea L.) and the effects of different treatments on nutrient content and effective Cd content of Cd contaminated soil, and Cd contents of peanut kernel, peanut shell and peanut stem leaf were studied. 【Result】The results show that compared to CK, BC significantly increases the soil pH by 0.91, O.M. by 21.71%, available Mg by 72.05%, available Si by 39.34%, and decreases available Cd content of soil by 11.63% (P ＜ 0.05). The soil pH had significantly negative correlation with available Cd content of soil (P ＜ 0.05). The BC can increase the yield of peanut pods by 22.57% and protein content of peanut kernel by 9.39% (P ＜ 0.05). The BC is beneficial to decrease the Cd content of peanut stem and leaf. 【Conclusion】Biochar+calcium-magnesium fertilizer is a blended material that can be used to improve the soils contaminated by heavy-metal Cd, and increase the yield and quality of peanut.