1. ENRICHMENT, RISK ASSESSMENT AND SOURCE IDENTIFICATION OF METAL LEAD IN CHANGHU RESERVOIR SEDIMENTS OF SOUTH CHINA.
- Author
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LI, R., ZHANG, S. Q., LONG, L. S., LEI, C., FU, Z. P., and MO, Y. D.
- Subjects
ECOLOGICAL risk assessment ,LEAD ,HEAVY metal toxicology ,SEDIMENTS ,RISK assessment ,WATER pollution ,HEAVY metals - Abstract
Evaluating the ecological risks of metals and identifying their sources is useful for preventing and controlling heavy metal pollution in water bodies. Four sediment cores (S1~-S4) were collected from the Changhu Reservoir of South China to determine lead (Pb) concentrations and geochemical fractions, as well as the isotopic compositions of core S1. The results show that Pb concentrations increased from the upstream site (S1:173.2 mg kg
-1 ) to the downstream site (S4:313.5 mg kg-1 ), resulting in a moderate to significant enrichment in the sediments. Sediment Pb in the geochemical fractions followed a decreasing order of residual (F4:54.7%) > reducible (F2: 23.1%) > oxidizable (F3: 16.6%) > acid-soluble fraction (F1: 5.8%). The geoaccumulation index (Igeo) and risk assessment code (RAC) showed that sediments were moderately polluted by Pb in S1 and S2 core, while sediments were moderately to heavily polluted in S3 and S4 core. The ecological risk of Pb in all sediment samples is generally at a low risk level, except for the sediments at a depth of 30-40 cm in the S4 core. Significant correlation between Pb concentration and206 Pb/207 Pb ratios suggested possible binary mixing of Pb. In the present study, mining activities, which was the major anthropogenic Pb source base on its isotopic composition, contributed significantly (means: 45.3-77.5%) to sediment Pb. The anthropogenic Pb in sediments is most likely to come from Sphalerite and Galena. [ABSTRACT FROM AUTHOR]- Published
- 2024
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