Climatic influence on Lake Stymphalia during the last 15 000 years

Abstract

Known from the ancient myth of Heracles fighting the Stymphalian birds, the karst polje of Stymphalia (22°27’E, 37°51’N) is an ideal site to study the climate history of the area. Stymphalia is the only natural perennial lake on the Northern Peloponnesus, which provides a continuous sedimentary record of the entire Holocene and a large part of the Last Glacial. As a large and quite reliable water reservoir, Lake Stymphalia and its surrounding karst springs played an important role for the water supply of the region from ancient time until today. However, due to climate fluctuations, the water supply can change significantly, challenging the water management of the people living in the area. Here we present geochemical analyses of the uppermost part of a lake sediment core (STY-1), recording the changes in climate and water supply during the Holocene and the Late Glacial. The chronology is based on several ¹⁴C dates combined to a Bayesian age-depth model. Using XRF elemental analysis, we compare the influx of terrestrial material (indicated by K and Rb) to the carbonate precipitation in the lake (indicated by Ca and Sr). The Rb/Sr ratio as a proxy for changes between dry/warm and wet/cold conditions indicate pronounced wet phases around 6800, 4000–3700–4000, 3500–3000 and 500–200 cal BP.