摘要
以受镉(Cd)单一污染的棕壤为供试土壤,分别添加不同用量(0、1%、3%和5%)的稻壳生物炭进行土壤培养试验,通过测定不同形态重金属Cd含量及土壤pH的变化,研究生物炭施用对棕壤中Cd赋存形态的影响;将培养后的土壤继续进行盆栽油菜的种植,测定不同时期油菜地上部及地下部的Cd含量,并计算其根富集系数及地上部转运系数,旨在探明生物炭的施用对油菜吸收Cd的影响。结果表明,随生物炭施用量的增加,活性较强的交换态Cd的含量显著降低,而活性较弱的有机结合态和残渣态Cd的含量显著增加(P<0.05);3%、5%的生物炭施用量提高了土壤pH,可交换态Cd与土壤pH存在极显著负相关关系(P<0.01),有机结合态、铁锰氧化物结合态和残渣态Cd与土壤pH存在显著正相关关系(P<0.05)。与对照相比,不同生物炭施用量(1%、3%和5%)处理的油菜地上部Cd含量分别降低了18.86%、64.22%、68.40%,地下部Cd含量分别降低了11.03%、57.93%、60.62%;油菜全生育期根富集系数减小值在0.01~1.26范围内,地上部转运系数减小值在0.22~0.32范围内,其中以生物炭施加量为5%的处理效果最佳。
An incubation experiment was conducted to investigate the effects of biochar derived from rice husk on cadmium（Cd）transforma-tion in brown soil. Biochar was applied at four rates（0, 1%, 3%, and 5%m/m）to the soil. The effect of biochar application on Cd uptake by baby bokchoi was studied by measuring the Cd contents underground and aboveground of baby bokchoi plants every 10 days in a pot exper-iment. The bioaccumulation factor of Cd underground and the translocation factor of Cd from underground to aboveground were also calcu-lated. Results showed that the contents of the exchangeable fraction of Cd significantly decreased and the organically bound fraction of Cd significantly increased, with the increase of biochar application（P〈0.05）. Compared with no biochar addition, 3%and 5%biochar appli-cation increased the soil pH. There was negative correlation between soil pH and the exchangeable form of Cd（P〈0.01）. There was positive correlation between soil pH and the organically bound form of Cd, the Fe and Mn oxide bound forms of Cd, and the residual form of Cd（P〈 0.05）. The Cd contents aboveground of the baby bokchoi plants for the 1%, 3%, and 5%biochar application decreased 8.86%, 64.22%, and 68.40%, respectively, compared with no biochar addition, and the Cd contents underground decreased 11.0%, 57.9%, and 60.6%, re-spectively. The Cd bioaccumulation factor underground decreased 0.01~1.26 and the Cd translocation factor from underground to above-ground decreased 0.22~0.32. Thus, 5%biochar application should be considered a suitable soil amendment for Cd.
出处
《农业环境科学学报》
CAS
CSCD
北大核心
2017年第5期907-914,共8页
Journal of Agro-Environment Science
基金
国家自然科学基金项目(41301530)
农业部环境保护科研监测所开放基金项目
农业部东北耕地保育重点实验室开放基金~~
关键词
生物炭
CD
赋存形态
富集系数
转运系数
biochar
Cd
transformation
bioaccumulation factor
translocation factor
