Tao Yuqiang, Zhang Shuzhen, Jian Wei, Yuan Chungang, Shan Xiao-quan
State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, China.
Chemosphere. 2006 Nov;65(8):1281-7. doi: 10.1016/j.chemosphere.2006.04.039. Epub 2006 Jun 5.
Oxalate is exuded by plants in the rhizosphere and plays an important role in the soil/root interactions. Phosphate fertilizer is widely used all over the world and may influence the behavior of arsenic (As) in soils. In this study oxalate and phosphate were used as extractants to investigate their effects on the release of As from three As-contaminated soils and the chemical speciation of As. Concentrations of arsenite (As(III)) and arsenate (As(V)) released progressively increased by increasing the concentrations of oxalate or phosphate. The released As(V) content was higher than that of As(III) and the differences between As(V) and As(III) released by oxalate was more obvious than by phosphate. Greenhouse experiment was conducted to evaluate the effects of oxalate and phosphate on As uptake by wheat (Triticum vulgare L.). Addition of oxalate or phosphate resulted in the increase of As accumulation in both wheat root and shoot and the effect of phosphate was more obvious than that of oxalate.
草酸由植物在根际分泌，在土壤/根系相互作用中发挥重要作用。磷肥在全球广泛使用，可能会影响土壤中砷（As）的行为。本研究中，草酸和磷酸盐被用作提取剂，以研究它们对三种受砷污染土壤中砷释放及砷化学形态的影响。随着草酸或磷酸盐浓度的增加，亚砷酸盐（As(III)）和砷酸盐（As(V)）的释放浓度逐渐增加。释放的As(V)含量高于As(III)，草酸释放的As(V)和As(III)之间的差异比磷酸盐更明显。进行了温室试验，以评估草酸和磷酸盐对小麦（Triticum vulgare L.）吸收砷的影响。添加草酸或磷酸盐导致小麦根和地上部砷积累增加，磷酸盐的影响比草酸更明显。
