以长春近郊蔬菜种植区土壤为研究对象，研究了土壤中As、 Hg含量的分布特征及其潜在生态风险。结果表明：研究区域内蔬菜土壤中As、 Hg的含量均低于国家土壤环境质量Ⅱ级标准值，即土壤中As、 Hg含量基本上不会对植物生长造成危害，适合于蔬菜种植，但As、 Hg含量普遍超过了长春市土壤背景值，且呈现出明显的累积效应。分布特征表明：长春市近郊蔬菜土壤中As、 Hg含量可能主要来源于煤炭等燃料的燃烧，最终通过干湿沉降进入土壤，其中东北与西南区域土壤中As、 Hg含量最高。相关性分析表明， As、 Hg具有一定的同源性，与有机质显著相关，而由于人类活动的影响， As、 Hg含量均与pH无显著相关性。总体上菜地土壤具有低潜在生态风险，但局部地区达到了较强的生态危害程度； As呈现低度潜在生态风险，而Hg具有较强潜在生态风险，故应着重加强控制Hg的输入量。图2，表3，参15。%The vegetable soils in Changchun suburb were investigated to study the concentration , distribution characteristics and poten-tial ecological risk assessment of As ,Hg.The results indicated that the concentrations of As and Hg were lower than the China Soil En -vironment Quality Standard level II ,,that is,the concentrations of As and Hg in soil were not detrimental to plant growth and thus suit -able for vegetable planting ,however they both generally exceeded the Changchun baseline values .Distribution characteristics showed that coal burning in industries was the main source of As and Hg ,and the highest contents of As ,Hg were both located in the northeast and southwest part of Changchun suburb .The correlation analysis showed As and Hg had the same source ,and there was no significant correlation between the contents of As and Hg and pH due to the influence of anthropogenic activities ,but the contents of As and Hg were positively related with organic matter .In general,vegetable farm soil possessed slight potential ecological risk ,but some areas reached strong potential ecological risk .Since As exposed low potential risk while Hg possessed high potential ecological risk ,more at-tention needs to be paid to control the input of Hg .
展开▼
