[Effects of different forms of P fertilizers on phytoremediation for As-contaminated soils using As-hyperaccumulator Pteris vittata L].

Fertilization has become one of the essential measures for enhancing efficiency of phytoremediating contaminated soils with heavy metal. In order to screen optimal P fertilizer for As-phytoremediation, a greenhouse study was conducted on the growth, As-accumulation and uptake of N, P and K by Pteris vittata L. in As-contaminated soils with different forms of P fertilizers. The results indicated that the biomass of plant with As addition decreased compared to no As-addition treatments except fused calcium magnesium phosphate (CaMg-P) treatment. The plants in As addition soils with CaMg-P, calcium dihydrogen phosphate (CDP) and di-ammonium phosphate (DAP) had higher biomass than those with other P fertilizer and control (0.83 g/pot). The As accumulations of plant aboveground in As addition soils are in order of CDP > CaMg-P> DAP> Potassium Phosphate Monobasic > Monosodium phosphate > control > Calcium superphosphate. The efficiency of As removal from As addition soils with CDP was the highest, 7.28%. Thus it can be seen the ability of phytoremediation using P. vittata could be improved by P fertilization, which CDP should be recommended preferentially and CaMg-P and DAP is considered as replaceable fertilizer for sake of pH, N, P and available As in phytoremediated soils.