Geochemical Trends in Sediments From 13 Italian Subalpine Lakes

摘要: Twenty-two selected cores from 13 lakes of the subalpine region northern Italy were collected and analyzed for nutrient (carbon [C], nitrogen [N], phosphorus [P], photosynthetic pigments) trace element (Cd, Cr, Cu, Hg, Pb, Zn) distributions. The enrichment factors nutrients, determined by 137Cs activity in sediment profiles, ranged typically 1 to 3 can be as high 6 heavily eutrophicated lakes. About 80% present a considerable or degree contamination, pollution is most noticeable since 1974. There are Cd (Lake Lugano/Ponte Tresa basin), Hg Como/Como Zn Garda/Desenzano Garda/Peschiera). Over last 30 years, impact human activities has been serious Annone Ovest, Segrino, Monate, Est. A modified sedimentologic approach (Hakanson, 1980) applied estimate risk elements each lake. Thus, it possible establish priorities aquatic control programs, focusing attention on those that show highest factors.