摘要
吸附作用是影响土壤中可溶性有机碳(DOC)迁移转化及生物有效性的重要过程,研究DOC在土壤中的吸附行为,对正确阐明土壤有机碳的循环和转化特征以及污染风险评估具有重要意义。选择具有代表性的3种土地利用方式的紫色土为实验材料,采用平衡吸附法研究了紫色土对分离的有机肥提取液中可溶性有机碳(DOC)的吸附特征,并分析了温度、磷酸盐、铁盐和有机质与DOC吸附量之间的关系。结果表明,原始物质吸附等温线方程可以反映土壤对可溶性有机碳的吸附特性,土壤对DOC的吸附量与DOC添加量呈极显著线性关系。从原始物质吸附等温线方程的分配系数看,随着温度的升高,土壤对DOC的吸附亲和力呈现降低趋势,5、15、25和35℃下,土壤对DOC的平均吸附率分别为26.38%、22.68%、19.98%和19.42%,其淋失迁移问题值得被重视。磷酸盐能抑制土壤对DOC的吸附,铁盐则促进土壤对DOC的吸附。有机质是影响土壤DOC吸附量的重要因素,用H_2O_2去除土壤部分有机质后,土壤对DOC的吸附量明显增大。
Soil adsorption significantly influences translocation, transformation and bioavailability of dissolved organic carbon (DOC). Studies on DOC adsorption are crucial to elucidate the cycling and transformation of soil organic carbon and assess the risk of contamination in polluted soils. In this study, dissolved organic carbon (DOC) was extracted from manure, and its adsorption characteristics on the purple soils were investigated with the batch equilibrium technique. The results showed that the adsorption in the soils could be fitted by initial mass isotherm model, and the adsorbed amounts of DOC had a significant linear relationship with the initial concentrations of DOC added into soils. The partition coefficient of the initial mass isotherm model, indicated that theadsorption affinity of DOC was gradually decreased with increasing temperature. The average adsorption rate of DOC in the soilswas 26.38%, 22.68%, 19.98% and 19.42% at 5℃, 15℃, 25℃ and 35℃, respectively. Phosphorus in solution prevented the adsorption of DOC, whereas ferrous sulfate increased the DOC adsorption. Soil organic matter contents significantly influenced DOC adsorption. After the soils were treated by H2O2 (deprived organic matter partially), DOC adsorption amounts increased significantly.
作者
李太魁
杨小林
寇长林
张香凝
郭战玲
LI Taikui;YANG Xiaolin;KOU Changlin;ZHANG Xiangning;GUO Zhanling(Institute of Plant Nutrition, Resources and Environmental Science, Henan Academy of Agricultural Sciences, Zhengzhou 450002, China;Safety and Emergency Management Research Center, Henan Polytechnic University, Jiaozuo 454000, China)
出处
《生态环境学报》
CSCD
北大核心
2016年第11期1836-1841,共6页
Ecology and Environmental Sciences
基金
国家科技支撑计划项目(2012BAD15B02)
国家科技重大水专项(2012ZX07205-001)
