滇池东大河湿地沉积物重金属空间分异特征及生态风险评价  

Spatial distribution and ecological risk assessment of heavy metals in sediments of Dongda River wetland in Dianchi Lake

作　　者：岑言霸 苏斌 陈越豪 徐瑞[1] 史正涛[1] CEN Yanba;SU Bin;CHEN Yuehao;XU Rui;SHI Zhengtao(Ynunan Key Laboratory of Plateau Geographical Processes and Environmental Changes,Faculty of Geography,Yunnan Normal University,Kunming,650500,China)

机构地区：[1]云南省高原地理过程与环境变化研究重点实验室,云南师范大学地理学部,昆明650500

出　　处：《环境化学》2023年第4期1313-1324,共12页Environmental Chemistry

基　　金：云南师范大学研究生科研创新基金(YJSJJ21-B86);云南师范大学博士科研启动项目(01300205020503197)资助.

摘　　要：湖滨湿地是重金属富集和转换的场所.为了解滇池东大河湿地沉积物重金属的污染特征及环境风险,根据东大河湿地的水域特征采集了28个沉积物样品,采用原子吸收光谱仪火焰法测定Zn、Cu、Ni、Pb、Cr的含量,并分析其空间分布特征,使用地质累积指数法和潜在生态风险指数法评价了湿地沉积物重金属的生态风险.结果表明,东大河湿地沉积物Zn、Cu、Ni、Pb、Cr的质量浓度分别是70.07—348.56、11.09—50.72、12.91—51.81、33.23—265.87、90.36—241.87 mg·kg^(-1).东大河湿地沉积物5种重金属的空间分布格局具有明显的规律性和相似性,5种重金属的平均含量均呈现出湿地中部>东部>西部的特征,在湿地水体入口附近积累,在人类活动频繁的区域和排水渠连通区出现高值区,人类活动是影响东大河湿地沉积物重金属差异的主要驱动因子.东大河湿地沉积物5种重金属在河流和排水渠入口处的个别样点达到中度污染和偏中度污染,其余大部分样点为轻度污染或无污染;单一重金属潜在生态风险指数表明Pb在河流入口附近达到中等生态危害,其他样点重金属均为轻微生态危害,综合潜在生态危害指数为轻微生态危害,湿地3个区域的综合潜在生态危害指数由大到小依次为:湿地中部>湿地东部>湿地西部.The lakeside wetland is a place where heavy metals are enriched and converted.In order to understand the pollution characteristics and environmental risks of heavy metals in the sediments of the Dongda River Wetland in Dianchi Lake,28 sediment samples were collected according to the water characteristics of Dongda River wetland.For the samples,the content of Zn,Cu,Ni,Pb,and Cr was determined by the flame method of atomic absorption spectrometer,and the spatial distribution characteristics of heavy metals in the sediments were analyzed.In addition,the ecological risk of heavy metals in wetland sediments was evaluated by geoaccumulation index method and potential ecological risk index method.The results indicated that the contents of Zn,Cu,Ni,Pb,and Cr in Dongda River wetland are respectively 70.07—348.56,11.09—50.72,12.91—51.81,33.23—265.87 and 90.36—241.87 mg·kg^(-1).The spatial distribution patterns of five heavy metals in Dongda River Wetland sediments have obvious regularities and similarities.The average content of the five heavy metals all present the characteristics of the central>the eastern>the western parts of the wetland.Heavy metals accumulate near the entrance of wetland water,and high-value areas appear in the areas of frequent human activities and drainage channels.Human activities are the main driving factors affecting the difference of heavy metals in the sediments in Dongda River wetland.5 kinds of heavy metals in the sediments of Dongda River wetland detect moderately polluted and moderately to strongly at individual sample points at the entrance of rivers and drains,and most of the remaining samples points are unpolluted to moderately polluted or practically unpolluted.Pb of the single potential ecological risk detected moderate near river entrances,and other sample heavy metals are mild.The comprehensive potential ecological risk is a minor.Above all,comprehensive potential ecological risk of three areas in the wetland from large to small:the central wetland>wetland east>wetland wes

关 键 词：湿地重金属 生态风险评价 东大河 滇池 

分 类 号：X52[环境科学与工程—环境工程] X826