砷对土壤-蜈蚣草系统中磷生物有效性的影响

Phosphorus availability in soil-Pteris vittata L. system affected by arsenic

磷是植物必需的大量营养元素,而其同族元素砷却不是植物生长发育所必需的。通过等温吸附平衡实验发现土壤中存在的砷可以降低褐土对磷的吸附,褐土对砷的吸附率大于等于褐土对磷的吸附率。对砷超富集植物蜈蚣草而言,土壤中砷的添加量不超过800mgkg时,蜈蚣草地上部和地下部磷含量显著提高,结果初步表明,砷可以提高土壤中磷的生物有效性。

Both phosphorus and arsenic belong to the V family on the periodic table of chemical elements. Phosphorus is an essential nutrient element to plant while arsenic is an unessential nutrient to plant. Batch experiment and pot experiment were conducted to understand the effects of arsenic on phosphorus sorption in cinnamon soil and phosphorus uptake by arsenic hyperaccumulator Pteris vittata L. The results indicated that phosphorus sorption was mediated by arsenic addition. The capacity of phosphorus sorption in cinnamon soil was not greater than that of arsenic sorption, Moreover the arsenic addition was less than 800 mg/kg in pot experiment, the concentrations of phosphorus in shoot and underground part of P. vittata were all increased with increasing of arsenic addition, The results represented that bio-availability of phosphorus to P, vittata L, can be improved by arsenic addition in cinnamon soil.