Effects of combining biochar and sulfur compounds on cadmium accumulation in rice and the soil microbial community
To investigate the suppressive impact of biochar and sulfur compounds(sodium and manganese sulfates)on cadmium accumulation in rice,a pot experiment was conducted to explore the effects of these compounds applied individually and in combination on cadmium accumulation in rice,soil physicochemical properties,enzyme activity,and microbial community.Significant reductions in cadmium concentrations in brown rice were observed when either biochar or sulfur compounds were applied,compared to the control treatment without these amendments.The most significant reduction in cadmium concentrations in brown rice occurred with the treatment combining biochar and manganese sulfate,with a reduction from 0.57 mg·kg-1 to 0.19 mg·kg-1,meeting the national food safety standard.Furthermore,sulfur and manganese concentrations in rice roots and straw significantly increased,with sulfur levels rising between 53.42% and 68.91% and manganese levels increasing by 38.17% to 42.62% .Soil pH increased significantly by 0.31 values,accompanied by significant increases in the availability of sulfur and manganese,as well as in the activities of urease,dehydrogenase,and sucrase.Conversely,there was a significant decrease in the available cadmium content,with a reduction of 41.56% .Additionally,the combined application of biochar and manganese sulfate increased the relative abundance of dominant bacterial phyla in rhizosphere soils,particularly Chloroflexi,Firmicutes,Desulfobacterota,and Proteobacteria.Redundancy analysis unveiled a negative correlation between Chloroflexi,Firmicutes,Desulfobacterota,and Proteobacteria and the bioavailability of cadmium in soil.Thus,combined application of biochar and manganese sulfate increased sulfur and manganese concentrations in rice,improved soil physicochemical properties and the bacterial community,enhanced soil enzyme activity,and reduced the bioavailability of cadmium in soil,thereby reducing the accumulation of cadmium in rice.
ricecadmiumbiocharsulfur compoundsbacterial community
万方数据
维普
