天津3种类型湿地土壤污染状况及潜在生态风险评价  

Soil pollution and potential ecological risk assessment of three types of wetlands in Tianjin

作　　者：刘凡惠 贾美清[2] 张国刚[1] 高志伟 刘美琪 王嘉宝 LIU Fanhui;JIA Meiqing;ZHANG Guogang;GAO Zhiwei;LIU Meiqi;WANG Jiabao(College of Life Sciences,Tianjin Normal University,Tianjin 300387,China;Tianjin Key Laboratory of Water Resources and Environ-ment,Tianjin Normal University,Tianjin 300387,China)

机构地区：[1]天津师范大学生命科学学院,天津300387 [2]天津师范大学天津市水资源与水环境重点实验室,天津300387

出　　处：《天津师范大学学报（自然科学版）》2020年第5期30-36,共7页Journal of Tianjin Normal University：Natural Science Edition

基　　金：国家自然科学基金资助项目(31500365,31770499,31100330,31270502);天津市自然科学基金资助项目(12JCYBJC19700,18JCYBJC96500);天津市科技支撑资助项目(15ZCZDSF00410).

摘　　要：为了解和科学评价天津不同类型湿地土壤的污染状况,以宝坻水稻田、北大港湿地、大黄堡湿地为研究对象,分别代表典型的农田湿地、滨海湿地和沼泽湿地,对各湿地0~30 cm土层的土壤理化性质以及As、Cd、Cr、Cu、Ni、Pb、Zn 7种重金属含量进行测定分析.通过计算钠吸附比和碱化度,确定3种类型湿地土壤的碱化程度.采用单因子指数法和内梅罗综合污染指数法相结合的方法,对土壤重金属的污染程度进行评价.根据Hakanson的潜在生态风险指数法,探讨土壤重金属的潜在生态风险.结果表明:天津湿地土壤存在一定程度的污染,且不同类型的湿地土壤受到的污染类型有所差异,其中,农田湿地受重金属污染程度高,滨海湿地土壤积盐程度高,沼泽湿地土壤pH值较高.湿地土壤的盐渍化程度与碱化程度具有一致性,为滨海湿地>沼泽湿地>农田湿地.不同类型湿地土壤的重金属含量存在差异,表现为农田湿地土壤中的Cd、Cr含量显著高于滨海湿地和沼泽湿地的含量.单因子污染指数表明,Cd在农田湿地和沼泽湿地中处于中度污染,在滨海湿地中处于轻度污染;综合污染指数表明,农田湿地和沼泽湿地处于中度污染水平,滨海湿地处于轻度污染水平.潜在生态风险指数表明,除Cd处于中度风险等级外,其他元素均处于轻度风险等级.天津3类湿地整体上都属于轻度风险,Cd为潜在生态风险的主要贡献因子.To investigate and provide scientific evaluation for the soil pollution in different types of Tianjin wetlands,Baodi paddy field,Beidagang wetland and Dahuangpu wetland were chosen as the representatives of typical farmland wetland,coastal wetland and swamp wetland,respectively.The physiochemical properties and the contents of As,Cd,Cr,Cu,Ni,Pb and Zn in 0-30 cm soil layer in each wetland were detected and analyzed.Sodium adsorption ratio and exchangeable sodium percentage were calculated to determine the alkalinity degree of three types of wetland soils.Single factor contaminant index and Nemero com-prehensive pollution index were used to evaluate the pollution degree of heavy metals in soil.The potential ecological risk of soil heavy metals was discussed according to the potential ecological risk index of Hakanson.The results showed that there was a certain degree of pollution in Tianjin wetland soil,and the pollution type in different kinds of wetland soil was different from each other.Among them,farmland wetland was highly polluted by heavy metals,coastal wetland had high soil salinity and swamp wetland had high soil pH value.The salinization degree of soil was consistent with the alkalization degree,the order of which was coastal wetland>swamp wetland>farmland wetland.The content of heavy metals in different types of wetland soil was different,and the content of Cd and Cr in farmland wetland soil was significantly higher than that in coastal wetland and swamp wetland.Single factor contaminant index showed that Cd was in moderate pollution level in farmland wetland and swamp wetland,and was in mild level in coastal wetland.Composite pollution index showed that farmland wetland and swamp wetland were in moderate pollution level,and coastal wetland was in mild pollution level.The single factor potential ecological risk index showed that all the heavy metals were in mild risk level except Cd.On the whole,the three types of wetlands in Tianjin were all in mild risk,and Cd was the main contribution factor of poten

关 键 词：天津湿地 土壤盐碱化 重金属污染 生态风险评价 

分 类 号：X825[环境科学与工程—环境工程]