摘要
The present study gives a detailed analysis of HM （heavy metals） accumulation in mollusks Nodularia （Bivalvia, Unionidae） from the transboundary part of the Amur River （Russia-China）. This river basin experiences different levels of toxic pollution. Differences in the rate of HM bioaccumulation in mollusks are identified depending on their size, sex （male and female）, content of HM in environment, and ratio of accumulating macro- and micro-components in tissue. Mollusks＇ response to the change of HM content in the environment is expressed in the different intensities of their accumulation in tissue. The possibility of estimating toxic danger for mollusk according to the index of HM bioaccumulation with consideration of frequency of pathologies is shown. These indexes permitted estimation of the ecotoxicological condition of the mollusks population in the parts of the Amur, upstream and downstream of the inflow of the Sungari River and before and after the accidental pollution, respectively. It is found out that mollusks are able for bioremediation when pollution of the aquatic environment decreases. Quantitative correlation of HM bioaccumulation index in mollusks to HM content in the environment makes it possible to forecast the population condition, and to substantiate the necessity of ecological control of anthropogenic load on the ecosystem.
