Assessing the impacts of human activities and soil erosion on the water quality of Plastira mountainous Mediterranean Lake, Greece

摘要

Human activities such as agriculture and tourism impose significant pollution threats in protected lake catchments worldwide. Plastira Lake is a highly touristic, artificial lake which is protected under the Natura 2000 European protection network. In this paper, the impacts from human activities, land uses and soil erosion on the lake's water quality have been identified and quantified. Hydro-morphological and physicochemical data were collected bimonthly in 17 sites, both in the lake and in the associated catchment's tributaries. Moreover, a soil erosion model was applied to estimate the annual soil erosion potential of the study catchment and identify its relationship with specific metal concentrations in the lake. A statistical analysis was conducted in order to ascertain the existence of a potential relationship between the basin's total nitrogen (TN) and phosphorus (TP) loads and the relevant TN and TP concentrations in the lake. The results revealed the significant effects of human pressures in the lake catchment, the magnitude of which is still relatively low. The lake's trophic status is mesotrophic with a tendency to eutrophy, and the existing soil erosion regime affects through the river tributaries, the lake's phosphorus and Fe balance.