Bio-concentration of Heavy Metals in Bungarus multicinctus in Wanshan Mercury Mining Area
The snake,as a high trophic level predator,is regarded to be a appropriate biological indicator for evaluating envi-ronmental heavy metal pollution.In this paper,Bungarus multicinctus existing in Wanshan mercury mining area and the surrounding region of Guizhou Province was investigated about the bio-concentration characteristics of heavy metal elements contained in this species of snake.Lab assays were conducted with the samples of dead Bungarus multicinctus(killed by road traffic vehicles)collected from Wanshan mercury mining area,Yangtou township(downstream of the Wanshan mercury mine)and Mount Fanjing(as a control area).The contents of 10 heavy metal elements were analyzed specifically including Cr,Mn,Ni,Cu,Zn,Cd,Pb,As,Se and Hg contained in the tissues of Bungarus multicinctus(bones,muscles and skin),and the heavy metal pollution features in Bungarus multicinctus were studied,furthermore the pollution sources identified by a non-negative matrix model.The results obtained with regard to Wanshan mercury mining area showed the elevated levels of Hg,Se and As in the snakes(Bungarus multicinctus),especially,Hg that had the highest potential pollution risk,while the risks of other heavy metal elements were lesser;as to Yangtou township,the risk of heavy metal pollution was not high,with only moderate levels of Hg in the snakes;and as for Mount Fanjing,it was found the concentrations of Cr,Mn,Cd and Pb in Bungarus multicinctus were rather high,among which,Cd particlarly had led to serious contamination.In addition,heavy met-al elements were primarily enriched in the snakes'skin,next in the muscle tissues,and the results of the pertinent analysis showed that there existed a significantly positive correlationship between the snakes'skin and the tissues of bone and muscle in terms of content of the majority of heavy metal elements,so the skin could play a pretty good role as biological indicator.According to the analysis by use of non-negative matrix model,Hg and Se in Bungarus multicinctus were mainly originated from Hg mining activities,Cd,Pb,Mn and Cr mainly from natural sources,Zn and Cu largely from traffic transport,and Ni and As from multiple composite pathways.It is expected that this research results would provide a scientific basis for the pre-vention and control of environmental pollution in mercury mining areas,as well as for wildlife conservation.
万方数据
维普
