Elbaz-Poulichet Françoise, Seidel Jean-Luc, Casiot Corinne, Tusseau-Vuillemin Marie-Hélène
Laboratoire Hydrosciences, UMR 5569 CNRS, IRD, University Montpellier I and II, CCMSE, 34095 Montpellier cedex 5, France.
Sci Total Environ. 2006 Aug 15;367(1):278-87. doi: 10.1016/j.scitotenv.2005.11.009. Epub 2005 Dec 13.
The concentrations of dissolved trace elements (Li, B, Mn, Cu, As, Rb, Sr, Mo, Cd, Ba, Pb) in the Marne and Seine rivers in the Paris urban area were monitored over a 2-year period. The resulting data indicated moderate contamination of waters by the most toxic elements (Cu, As, Cd and Pb). The River Marne upstream and the River Seine downstream of the city of Paris displayed similar concentrations. However higher fluxes of trace elements were observed in the Seine than in the Marne due to their different discharges. Li, B, Rb, Sr and Ba concentrations were correlated with river discharge and concentrations were higher during high river flow. This was interpreted as a dilution by discharge from a major natural or anthropogenic source. Mn, Cu, Mo, Cd and Pb concentrations were not correlated with discharge. Dissolved Mn, Cu and Cd increased rapidly in summer, whereas the concentration of Mo decreased. These variations were attributed to redox processes. During summer when the dissolved oxygen concentrations decrease, Mn, Cu, Cd and Pb are released into solution whereas Mo is immobilised. Like metals, variations in arsenic contents were not linked with discharge. Its similarity with phosphate distribution suggests similar controls involving phytoplankton uptake and release from sediments through organic matter mineralization.
在两年时间内，对巴黎市区马恩河和塞纳河中的溶解态微量元素（锂、硼、锰、铜、砷、铷、锶、钼、镉、钡、铅）浓度进行了监测。所得数据表明，毒性最强的几种元素（铜、砷、镉和铅）对水体造成了中度污染。巴黎市上游的马恩河和下游的塞纳河呈现出相似的浓度。然而，由于塞纳河和马恩河的流量不同，塞纳河中观测到的微量元素通量高于马恩河。锂、硼、铷、锶和钡的浓度与河流流量相关，且在河流高流量期间浓度更高。这被解释为来自主要自然或人为源的排放造成的稀释作用。锰、铜、钼、镉和铅的浓度与流量无关。溶解态的锰、铜和镉在夏季迅速增加，而钼的浓度则下降。这些变化归因于氧化还原过程。在夏季，当溶解氧浓度降低时，锰、铜、镉和铅会释放到溶液中，而钼则会被固定。与金属一样，砷含量的变化与流量无关。其与磷酸盐分布的相似性表明，其受到类似的控制，包括浮游植物的吸收以及通过有机物矿化作用从沉积物中释放。
