摘要
本研究分析了杭州市西溪湿地不同地点表层沉积物重金属Cu、Zn、Cr、Pb和Ni的含量及季节分布特征,进一步运用单项和综合污染指数法、Hakanson潜在生态风险指数法分别对西溪湿地沉积物重金属进行了污染评价和生态风险评价.结果表明,空间分布上西溪湿地沉积物中重金属Zn的含量较Cu、Cr、Pb、Ni居首位,Zn含量范围为72.65～159.64mg/Kg.季节分布特征上Cu、Zn含量在一年中逐渐降低,基本在11月份最低,Cr、Ni含量均在9月份最高,Pb含量在各采样点全年波动趋势差异较大.从综合污染指数评价来看,五义桥沉积物全年均为轻度污染,普济桥和泊蓭沉积物中7月、9月和11月为轻度污染,4月达到安全等级,蒋相公桥沉积物在7月和9月达到轻度污染,4月处于警戒级,11月为安全等级.Hakanson潜在生态风险评价表明,西溪湿地的整体生态风险较轻微,全年的重金属综合潜在生态风险指数最高为五义桥.
This research analyzed the content and seasonal distribution characteristics of heavy metals including Cu, Zn, Cr, Pb and Ni in the sediments of different locations in Xixi wetland, and made pollution evaluation as well ecological risk assessment of these heavy metals by the individual and comprehensive pollution index and Hakanson potential ecological risk index. The results indicate the spatial distribution of Zn is more than Cu, Cr, Pb and Ni, and the content range of Zn is 72.65-159.64mg/Kg. The seasonal distribution of the content of Cu and Zn decreases gradually in a year and reaches the lowest value in November. Both the highest content of Cr and Ni is in September, but the content of Pb in each sampling point is different annually. The results of comprehensive pollution index evaluation show the pollution level of the sediments in Wuyi Bridge is slight throughout the year. Both the sediments in Puji Bridge and Boan cause mild contamination in July, September and November but reached safety level in April. The sediments in Jiang Xianggong Bridge is mild contamination level in July and September, alert level in April and safety level in November. Hakanson potential ecological risk assessment reveals overall ecological risk of Xixi wetland is minor and the potential ecological risk index of annual heavy metals in Wuyi Bridge is the highest.
出处
《杭州师范大学学报（自然科学版）》
CAS
2013年第2期161-167,172,共8页
Journal of Hangzhou Normal University(Natural Science Edition)
基金
浙江省重点科技创新团队项目资助(2010R50039)
杭州市西溪湿地研究中心开放基金资助项目(PD11001004002010)
浙江省大学生新苗人才项目(2011R421016)
关键词
西溪湿地
重金属
分布特征
评价
Xixi wetland
heavy metal
characteristics of distribution
assessment
