生态移民前、后神农架大九湖沼泽内锯齿藓中的重金属含量变化

Changes of Heavy Metal Concentrations in Prionidium setschwanicum in Bogs of Dajiuhu in Shennongjia before and after Eco-migration

苔藓作为监测大气污染的指示生物,在国内外被广泛应用于研究大气重金属沉降分布。为了研究神农架大九湖沼泽生态移民前、后大气重金属沉降变化状况,于2012年7月29日和2016年10月25日,在野外采集锯齿藓（Prionidium setschwanicum）样品,并测定其中的As、Cd、Cr、Co、Cu、Fe、Pb和Zn的含量,分析生态移民前、后大九湖沼泽锯齿藓中8种重金属的含量变化。研究结果表明,生态移民4 a后,锯齿藓中As、Cd、Cr、Cu、Pb和Zn含量都显著减少,分别减少了100%、43%、68%、42%、56%和76%。这与生态移民后该区人类活动减少有关,虽然仍存在因少量旅游交通造成的大气重金属沉降,但是,相对生态移民前,大九湖沼泽的大气环境质量得到了一定程度的改善。

As a biomonitor of atmospheric pollution, bryophytes have been widely used to study the atmospheric heavy metal deposition by researchers at home and abroad. In order to study the changes of atmospheric heavy metal pollutants before and after eco-immigration in Dajiuhu bog, Mt. Shennongjia, we detected the concentrations of eight heavy metals（As, Cd, Cr, Co, Cu, Fe, Pb and Zn） in epiphytic Prionidium setschwanicum, and analyzed the concentration characteristic of these eight heavy metals in Dajiuhu bog based on sample analysis of the field sampling on July 29, 2012 and October 25, 2016. The results show that the concentration of As, Cd, Cr, Cu, Pb and Zn in Prionidium setschwanicum have reduced significantly after eco-immigration, which decreased by 100%, 43%, 68%, 42%, 56% and 76% respectively. With aspects to human activities in the studying area, the sources of these elements in atmospheric dust fall are discussed in this paper. Although the traffic atmospheric pollution still exists after the eco-migration, the quality of atmospheric environment of Dajiuhu bog has been improved to some extent because of the decrease of anthropogenic disturbance after eco-migration.