【摘要】 为探究汞(Hg)对内蒙古地区草原土壤的影响,于2015年5月～2016年5月对呼伦贝尔(HB)、鄂尔多斯(ER)、霍林郭勒(HL)和锡林浩特(XL)电厂周边土壤Hg分布进行研究。设计采样路线,分别位于四个地区的东、西、南、北,每条路线上每隔5km布点,对土壤样品进行采集,并用原子荧光光度计(普析通用PF-7原子荧光光度计)对土壤中Hg含量进行测定。实验结果表明:四个地区土壤Hg含量的平均值均高于Hg在土壤中的背景值,受人为活动干扰明显;空间积累特征为:土壤中Hg的超背景值倍率由污染源的中心向四周逐渐递减,但各方向上的递减速率差异很大,各方向上的传输距离也有一定差异,其空间分布表现出明显的方向性;利用单因子指数法(P)和潜在生态危害指数法(Ei)对四个地区汞的污染程度及风险评价进行分析发现,PHB处于无污染状态,PER属于轻度污染,PHL和PXL属于中度污染; HB和ER地区分别属于强生态风险程度(Ⅲ级)、很强生态风险程度(Ⅳ级)、HL和XL地区属于极强生态风险程度(Ⅴ级)。更多还原

【Abstract】 The distributions of soil mercury around generating stations of hulunbuir( HB),ordos( ER),Holly gooler( HL) and Xilinhot( XL) from May 2015 to May 2016 were investigated to explore the influence of mercury( Hg) on grassland soils in Inner Mongolia.A sampling route in north,south,east and west regions of these generating plants was designed and soil samples were collected with an interval of 5 km on the route. The Hg contents of soil samples were determined by an atomic fluorescence photometer( PF-7 Atomic fluorescence photometer). The results showed that the average content of Hg in soil samples is higher than the background soil Hg content,indicating the obvious disturbance of human activities in the four sampling areas. The spatial distribution could be characterized as follows,the elevated levels of Hg in soils gradually decrease from the center of the pollution source to the periphery,but the deceleration rates of various directions are very different,and the transmission distances of various directions are also different,in other words,the spatial distribution shows obvious directional characteristics. The pollution degree and the risk evaluation of mercury in the four areas were estimated by single factor index method( P) and the potential ecological hazard index method( Ei). The results showed that PHLand PXLwere moderately polluted,regions of HB and ER belonged to the ecological risk degree( III level) and the strong ecological risk degree( IV level),respectively,and HL and XL areas belonged to the strong ecological risk degree( V level).更多还原