Characteristics and Fractionation of Phosphorus in the Sediments of Lake Liuhuahu in Guangzhou

The forms of phosphorus in the surface sediments of lake Liuhuahu in Guangzhou,Guangdong Province,China were investigated by sequential chemical extraction according to the improved scheme proposed by Psenner.The results showed that the contents of total phosphorus forms in the surfaces sediments ranged from 1.28?mg/g to 2.15?mg/g in lake Liuhuahu.The total sediment phosphorus consisted mainly of NaOH-P,OrgP and HCl-P.The concentration of different phosphorus forms followed the order: NaOH-P Org-P HCl-P BD-P NH_4Cl-P.Moreover,the bio-available phosphorus(BAP) contents ranged from 0.79?mg/g to 1.00?mg/g,and the average value was(0.91)(mg/g).Therefore,the potential phosphorus released from sediments to the overlying water and the availability of phosphorus for algal uptake in sediments of lake Liuhuahu were high.The effective methods should be taken to control phosphorus release from the sediments during the lake restoration.