Mljet Online

VELIKO AND MALO JEZERO

The small lake (the total volume 3,349,000 m3) is a karst depression filled with seawater. It is connected with the Large Lake by passage about 20 m long and 0.5 m deep. Its surface area is 24 hectares, the biggest depth is 29 m, and the shoreline length is 2,600 m.

The Large Lake is also a karst depression filled with seawater that enters it through the Soline Bay and the Big Bridge. The total volume of the Large Lake is 36,730,000 m3, the surface area 145 hectares, and the shoreline length 9,420 m.

The temperature in summer months is higher than the one on open sea; for instance, in Small Lake the temperature of 27 °C was recorded, in the Large Lake 29 °C, and in the Gonoturska Cove 17 °C. The salinity is also higher-27 ‰ in the Small Lake, 28 ‰ in the Large Lake, and in the Gonoturska Cove 17 ‰ (T. Vučetić, The 1995 Mljet Symposium). In the rainy season (winter) the salinity in the Small and Large Lakes is somewhat lower due to fresh water springs and inflow of rainwater. The average annual temperature of the sea surface in the Small Lake is 26 °C, which is higher than on the open sea. The average winter temperature is about 4.5 °C, which is lower than on the open sea. The salinity of the Small Lake increases towards the depth, which leads us to a conclusion that there is a direct underground connection with open sea. The explorations of the Lake in 1953 confirmed for the first time the presence of H2S in the waters of the Adriatic.

Prof. Schulze, who made explorations in the Small Lake in 1984, found the pollen of Aleppo pine dating back 2,000 years. In his study he explained the connection with the open sea and located the chasm.