A comparison has been made between the metal pollution in several European rivers in various stages of clean-up and management for the period of 1980-1996. The investigated rivers were Rhine, Meuse, Scheldt, Weser and Elbe. The results from this comparison showed that the simple statement that characterizes the river Elbe as 'the most polluted river in Europe' is a simplification. Three independent methods are presented to estimate point and diffuse source contributions in emissions and riverine transports. All methods were applied to the Elbe and Rhine rivers to estimate the contribution of point and diffuse sources for six heavy metals. The results of the source apportionment estimates show that there are temporal differences in source strength and source origin. A dramatic drop in industrial inputs and inputs from waste water treatment plants can be observed. The comparison of all methods shows some differences, which might be caused by retention processes (such as sedimentation) in the river system. |
