Effects of four phosphorus fertilizers on cadmium bioavailability in soil-leaf vegetables systems

A pot experiment was conducted to study the influences of four phosphorus on yield,cadmium(Cd) absorption and accumulation in leaf vegetables(spinach,pakchoi,willow leaf and round leaf amaranth) and the Cd availability in soil.Results showed that phosphate treatments could significantly promote vegetables growth,reduce the Cd concentrations in vegetable shoots and roots and increase Cd accumulation in four vegetables shoots compared with the control treatment.However,the Cd accumulation in the shoots didn't varied significantly with the phosphate treatments.A significantly negative linear relationship was found between soil pH and the available Cd.The capability of four phosphates in acidifying soil varied in following order:SSP(superphosphate)MAP(monoammonium phosphate),DAP(diammonium phosphate)DCP(dicalcium phosphate).The DCP treatment exhibited the highest yield,the lowest content of Cd in vegetable,the highest pH and the lowest soil available Cd.