A RECENT POLLUTION HISTORY OF THE MYGDONIA BASIN IN GREECE

Lakes Koronia and Volvi, located within the Mygdonia Basin in northern Greece, comprise an internationally protected wetland. The lakes support major industrial and agricultural activities, and a population of 45,000. Consequently, both sites have been greatly impacted by the conversion of marshland to farmland, water losses to irrigation, and pollution discharges including raw sewage, agricultural run-off, and industrial wastes. Lake Koronia, for example, has experienced lowered lake levels, degraded water quality, and loss of biodiversity in recent decades. Here, I propose to reconstruct recent pollution histories and the effects of human activities in the watersheds over the last century using short sediment cores from both lakes in an effort to develop more sustainable water use plans and to restore the general health of the combined Koronia-Volvi wetland. Sediment chronology and accumulation rates have already been determined in cores from multiple sites within the lakes using ²¹⁰Pb dating techniques. Bulk sediment elemental composition (organic carbon content, C/N ratios, etc.) and trace metal concentration (Pb, Cr and As, among others) will be measured to provide critical evidence for variations in land-use within watersheds. Stratigraphic variations in the carbon and nitrogen isotopic ratio of sedimented organic matter will also be measured to determine changes in aquatic ecosystem productivity. The geochemical results will be compared to historical records to determine the relative importance of disturbances caused by urban, agricultural, and industrial activities.