Accumulation of N,P and K in Pteris vittata L. during phytoremediation:A five-year field study

The As-hyperaccumulator Pteris vittata L.has been applied for phytoremediation of As-contaminated soil in field projects.In order to improve the removal efficiency,a five-year field trial was conducted to study the dynamics of N,P and K contents of soils and the accumulation of these elements in P.vittata during phytoremediation.The results showed that the total N contents of soils in 3 plots with different levels of arsenic decreased significantly (25%) while the total P or K contents of soils in the 3 plots did not decrease obviously by the end of five-years of remediation.The total N,P and K contents in shoots of P.vittata were 1.23～2.38,0.14～0.47 and 1.10～2.01 g·kg-1,respectively.The annual accumulation of N,P and K in P.vittata were 23～89,4.4～13.0 and 21～69 kg·hm-2·a-1,respectively.The total quantities of all nutrients accumulated by P.vittata from soils were less than that of rice and wheat,so nutrient deficiency might be a problem for growth of P.vittata without fertilizer during continuous remediation.