Impacts of biochar application on amelioration of heavy metal-polluted soil and maize growth
LI Yan-liang;HUANG Yu-fen;WEI Lan;HUANG Lian-xi;HUANG Qing;XU Gui-zhi;LIU Zhong-zhen;Institute of Agricultural Resources and Environment, Guangdong Academy of Agricultural Sciences;Key Laboratory of Plant Nutrition and Fertilizer in South Region, Ministry of Agriculture;Guangdong Key Laboratory of Nutrient Cycling and Farmland Conservation;School of Environment and Civil Engineering, Dongguan University of Technology;
In the present study, a field trial was adopted to study the effect of biochar application at different concentrations(0, 5, 10, 20 t·hm-2 and 30 t·hm-2)on the physicochemical properties of the heavy metal-polluted farmland soil near mining areas in Renhua, Shaoguan,China. In addition, we investigated the impacts of biochar on the growth and yield of maize(Yuetian 9)as well as on the accumulation of heavy metals in the crops. The results indicated that the addition of biochar significantly elevated the soil pH and organic matter fractions compared with the CK treatments, and the rate of increase was positively related to the amount of biochar applied. Conversely, the cation ex-change capacity of soil first increased and then decreased with an increase in the amount of biochar applied. When the biochar application amount was 30 t·hm-2, the content of available potassium in soil was approximately 3.1 times of that in the CK treatments; however, the ad-dition of different amounts of biochar showed no significant impact on the content of hydrolysable nitrogen in soil. The soil contents of Pb and Cd reduced by 11.3% and 23.9%, respectively, regardless of the application amount of biochar. A significant reduction was observed in the accumulation of Pb and Cd in the grain, cob, leaf, and stalk of maize in all biochar treatments. When the biochar application amount was30 t·hm-2, the contents of Pb and Cd in maize grain decreased by 49.4% and 45.4%, respectively. With the application of 5, 10, 20 t·hm-2 and 30 t·hm-2 biochar, the maize yields were 1.75, 6.16, 8.84 times and 8.90 times higher than that in CK treatment, respectively, indicat-ing that the maize yields increased with an increase in the amount of biochar applied. Overall, the application of biochar ameliorated the acidified soil in Southern China by increasing its pH and organic matter content, subsequently promoting the yield of maize and reducing the bioavailability of heavy metals in contaminated soils.
【Fund】： 国家自然科学基金项目(41571313 41401353 41401575);; 国家重点研发计划项目(SQ2017YFNC060046);; 广东省科技计划项目(2014A020216018 2016A020210034 2017A020203001 2017B020203002);; 有机地球化学国家重点实验室开放基金项目(OGL-201506)~~
【CateGory Index】： S513;X53
【CateGory Index】： S513;X53