Assessment of water pollution and suitability to fish life in six Italian rivers

This paper reports the results of a monitoring programme of six rivers (Ser chio, Cecina, Cascina, Era, Elsa and Pavone) that drain north-west Tuscany (Italy). In this area, agricultural, industrial and urbanization pressures affect water quality, also in terms of suitability for the survival of aqua tic organisms. The river waters were monitored for several physico-chemical parameters (temperature, dissolved oxygen, suspended solids, total ammonia , nitrites, Cu, Cd, Cr, Ni and Pb) in order to assess the anthropogenic imp act on the environmental conditions of these watercourses and their suitabi lity for fish life. Statistical data handling was performed for each river and the percentage of physico-chemical parameters that, according to the E. C. law, were over the limits that must not be exceeded to protect fish life , was calculated and a classification was made of the six rivers in this se nse. Concerning the metals, inter-element relationships (between chromium a nd nichel, lead and copper, nichel and lead and copper, copper and lead) we re found which allow some remarks on the origins of the anthropogenic impac ts, and comparisons were made with two metal-polluted watercourses in north ern Italy, the Po and Lambro rivers. From the comparison, the Tuscan rivers showed generally lower metal contamination, especially with respect to the Lambro.