Speciation Distribution Characteristic and Ecological Risk of Heavy Metals in Surface Sediments of Cascading Hydropower Dams in Lancang River

In order to study the speciation, contamination statues, and distribution characteristic of heavy metals in surface sediments cascading dams, reservoir regions Manwan Dachaoshan dams were sampled investigated. The speciation its contents (As, Cd, Cr, Cu, Pb, Zn) analyzed by modified European Community Bureau Reference (BCR) sequential method. ecological risk assessment was performed ratio secondary phase primary (RSP) source identification correlation analysis (CA) principal component (PCA). results indicated that values RSPcd from pollution (IV level), those RSPZn light (II level) moderate (III lacustrine zone upper-stream dam. RSP no (I downstream (Cd, Zn, As) at upper stream dam generally higher than Cascading operation showed significant accumulation effects on sediments. Cd Zn mainly anthropogenic activities; As, Pb affected both natural processes Cr processes.