【摘要】 开展河岸带不同土地利用类型下河流表层沉积物重金属污染状况研究对河流沉积物监测和下游滩涂湿地生态系统保护具有重要意义。通过对盐城新洋港河不同土地利用类型下河流表层沉积物中铬(Cr)、镉(Cd)、铜(Cu)、锌(Zn)、铅(Pb)、镍(Ni) 6种重金属含量进行测定,并采用Hakanson潜在生态危害指数法进行河流表层沉积物重金属生态污染评价。结果表明,在河岸带为耕地(样点1)和城镇建设用地(样点5)的河段Cu和Cd元素已经出现了超标现象,属Ⅱ类沉积物;在其余采样点Cu、Cd、Cr、Pb、Zn和Ni含量均低于国家Ⅰ类标准,属Ⅰ类沉积物。重金属的潜在生态危害指数Er值均小于40,总潜在生态危害指数RI值均小于120,总体属于等级较低的生态危害。研究显示河岸带不同土地利用类型对河流重金属含量有直接影响,主要表现为以城镇建设用地为主导的河流表层沉积物中重金属含量与风险都偏高,少数耕地河岸带采样点重金属危害指数也偏高,河岸带附近种植人工林和草坪对河流生态环境有明显改善。因此,合理规划城市河流河岸带土地利用类型将在一定程度上缓解人类活动产生的重金属对河流水质和下游湿地的污染。更多还原

【Abstract】 The contents of chromium(Cr),cadmium(Cd),copper(Cu),zinc(Zn),lead(Pb)and nickel(Ni) in the surface sediments of Xinyanggang River in Yancheng City were determined,with its heavy metals pollution evaluated by Hakanson Potential Ecological Risk Index(HPERI).Results showed that,in some riparian zones where the land use was cultivated and urban construction types,Cu and Cd had exceeded the standard,belonging to Class Ⅱ standard sediments.In other riparian zones,the contents of Cu,Cd,Cr,Pb,Zn and Ni reached the first class of national standard at each sampling point,belonging to Class Ⅰ standard sediments.Land use types of the river had an impact on different heavy metal content.The content and risk of heavy metal was high in urban constructive land and some cultivated land.The establishment of plantation and lawn obviously improved the environment of the river.更多还原