1. Key Laboratory of Aquatic Genetic Resources and Utilization,Ministry of Agriculture, Shanghai Ocean Lniversity, Shanghai 201306, China; 2. Project Management Office of Dayang Reservoir,Jinyun 321400, China; 3. Science and Technology 7 Promotion Centre of Water Resources in Zhe-jiang Province,Hangzhou 310012, China
Abstract: The spatial distribution of heavy metals Cu,Pb,Cd,Cr,Zn,As and Hg and nutrients carbon,nitrogen,and phosphorus in sediments were investigated in Dayang Reservoir in March,June and September in 2013 to evaluate their potential ecological risk（PER） and organic pollution.The results showed that the concentrations of the heavy metals was 19.50 mg / kg in Cu,86.19 mg / kg in Pb,0.41 mg / kg in Cd,2.44 mg / kg in Cr,126.7 mg /kg in Zn,3.46 mg / kg in As and 0.36 mg / kg in Hg,and 7.30% in total organic carbon（TOC）,0.27% in nitrogen（TN） and 0.099% in phosphorus（TP）,without significantly spatial differences in the concentrations of the heavy metals and nutrients.There was no significant differences in PER and pollution degree of heavy metals between two background reference systems or only one grade differences.Compared with the background values of the Jinqu Basin nearby Dayang Reservoir,the sediment of the reservoir was found to be moderately polluted,with pollution parameter（Cd） of 10.53.The pollution made by the 7 heavy metals ranged from low level to relatively high level,the maximal pollution degree by Hg and the minimal by Cr and As,with an average PER index（RI） of 181.63,indicating that the reservoir sediment was within the real moderate risk.The order of the PER of the 7 heavy metals was ranged as Hg,Cd,Pb,As,Cu,Zn and Cr,with moderate to relatively high PER for Hg,moderate PER for Cd and low PER for the other five heavy metals.The organic matter index（OI） and organic nitrogen index（ON） analysis revealed that the reservoir was seriously polluted by organic materials and organic nitrogen.
2016, Vol. 31 
