Effects of Vermicompost on Soil Acidity and Cu/Pb Chemical Speciation
ZHOU Bo;TANG Jinchi;ZHANG Chi;WU Jialong;LI Jianlong;GUO Yanbiao;TANG Hao;DAI Jun;Tea Research Institute,Guangdong Academy of Agricultural Sciences/Guangdong Key Laboratory of Tea Plant Resources Innovation and Utilization;College of Natural Resources and Environment,South China Agricultural University/Key Laboratory of the Ministry of Agriculture for South China Farmland Conservation/Guangdong Key Laboratory of Land Use and Rehabilitation;
The effects of vermicompost produced by Eisenia foetida on organic carbon content,soil acidity and Cu/Pb speciation were studied in acid soil contaminated by heavy metals through simulated pot experiment.Vermicompost was made with cattle waste and rice straw,respectively.The results showed that soil total organic carbon content increased by 25%~83%in the soil with 2.5%~10% amount of vermicompost,and the soluble organic carbon of the cattle waste vermicompost was significantly higher than that of the rice straw vermicompost(P0.05),and there was no significant difference in other organic carbon content between the two kinds of vermicompost.Vermicompost increased the soil pH(H2O)value by 0.38~1.13 pH units,and reduced exchangeable hydrogen and aluminum content by 41% ~77% and 57% ~94%,respectively.The vermicompost reduced soil acidity significantly,and soil pH(H2O)value was 0.35~4times higher than that of the control.For reducing acidity of the soil with 10%amount of vermicompost,the effect of cattle waste vermicompost was 22% higher than that of rice straw vermicompost.The vermicompost reduced the contents of soluble-exchangeable Cu and Pb in the soil by 19%~56%and 10%~40%,respectively,and increased the contents of organic state Cu and Pb by 22% ~70% and 29% ~70%,respectively.Thevermicompost could significantly reduce the activity of Cu and Pb in soil.The effects of vermicompost on reducing Cu and Pb activity were 0.58~9.6times and 0.16~3.4times higher than those of the control.The effects of rice straw vermicompost on reducing activity of Cu and Pb were 11%~61% and 1%~32% higher than those of cattle waste vermicompost.In conclusion,vermicompost reducd soil acidity and Cu/Pb activity greater than that of control,cattle waste vermicompost was better on reducing soil acidity,and rice straw vermicompost was better on reducing Cu/Pb activity.The total organic carbon,microbial biomass carbon,Humic acid carbon and fulvic acid carbon in vermicompost all played important roles in reducing soil acidity.Cu and Pb activity,and the action efficiencies of organic carbon in the vermicompost on soil acidity and Cu/Pb activity were higher than those in the control material with the same amount of organic carbon.
【Fund】： 国家重点研发计划项目(2016YFD0200900);; 广东省自然科学基金项目(2016A030313773);; 广东省科技计划项目(2014A020208054 2015A020224017);; 清远市科技计划项目(2014A015)
【CateGory Index】： S153
【CateGory Index】： S153