摘要
P和As的化学性质相近,在土壤中存在竞争吸附的关系,因而土壤中P浓度增加可能会影响As的固定和活化。本文通过等温吸附和浸提实验,模拟施P对黄棕壤中As固定和活化的影响。实验结果表明,提高溶液P浓度能够减少土壤对As的吸持能力,并增加As从土壤中的解吸量。在P浓度较低的情况下,这种影响尤其显著,As的解吸量与P浓度成极显著的线性相关关系。因此,不能忽视施用P肥对土壤As活化和迁移的影响。持续增加溶液的P浓度时,这种影响的程度逐渐减弱,可能与土壤中存在不同类型的吸附位有关。
Arsenic and phosphorus are similar in chemical properties and compete with each other for sorption sites in soil. Effect of phosphorus on adsorption of arsenate in yellow-brown soil was evaluated in a batch experiment. Solutions different in P concentration were also used to extract As from the As contaminated soil. The results showed that when P concentration was low, the rise in P concentration might significantly reduce As adsorption but increase As extraction from the soil. When P concentration further increased, the changes in As adsorption and desorption became not so distinct. Sorption of As （V） even in the presence of high concentrations of P may be attributed to presence of sorption sites specific for As （V） and P and other sites that are common for both. Results of this study indicate that application of phosphate-containing fertilizer to As-contaminated soils may increase soil As solubility, phytoavailability and potential of leaching to groundwater.
出处
《土壤》
CAS
CSCD
北大核心
2005年第6期645-648,共4页
Soils
基金
中国科学院知识创新工程重要方向项目(KZCX3-SW-417)资助。
关键词
磷
砷
吸附
活化
土壤
Phosphorus, Arsenic, Adsorption, Mobilization
