磷对土壤中砷吸附的影响

Effect of phosphorus on arsenic adorption by three different soils

在黄壤、红壤和褐土中进行As的等温吸附实验表明 ,在不添加P的情况下 ,3种土壤对As的吸附能力随土壤 pH的升高而降低 ,随土壤粘粒含量的降低而减弱 ,3种土壤吸附能力为黄壤 >红壤 >褐土 .As在土壤中的吸附受P存在的影响 ,6 0mg·kg-1的P可以降低黄壤和红壤对As的最大吸附量 .吸附质中P∶As的比例不同 ,P对土壤吸附As的影响差异很大 :吸附质中P∶As =1∶2时 ,土壤对As的吸附能力均强于P∶As =1∶1和P∶As=2∶1,后两者差异不显著 ,表明土壤中的吸附点位对As和P的亲和性具有一定的差异 .

The effect of phosphorus on arsenic adsorption by yellow soil, red soil and brown soil was studied using batch experiment. The results indicated that the arsenic without P amendment adsorption capacity of three tested soils was yellow soil>red soil>brown soil.The maximal adsorption capacity of yellow soil and red soil was decreased with 60 mg·kg -1 phosphorus added,and that of brown soil was increased with 20 mg·kg -1 phosphorus added.The arsenic adsorption capacity of three soils was greater when P∶As=1∶2 than that when P∶As=1∶1 and P∶As=2∶1, and the differences between P∶As=1∶1 and P∶As=2∶1 treatments were not significant. Observations could be better fitted by Langmuir equations.