Geological development of a gypsum lake formed at the beginning of the 20th century in central Sicily, Italy: Integration of historical data with modern survey techniques.

A limnological investigation was carried out on the small, endorheic lake, called Lake Sfondato, located in central Sicily (Italy). All the aquatic environments in the central part of the island are rich in salt, with conductivity values above 5 mS cm -1 , and are characterized by high alkalinity values and hard waters. In addition, due to intensive agriculture, many of these ecosystems have experienced a strong anthropogenic eutrophication over the last decades. In order to better understand the functioning of these peculiar environments, the morphology, hydrology, and geochemistry, as well as several selected physical and biological characteristics of Lake Sfondato, were studied in the years 2003 and 2004. The results showed that the water body is characterized by meromixis, with permanent water stratification. This condition reduces the eutrophication processes within the lake, which have kept the trophic conditions constant over the last 50 yr. [ABSTRACT FROM AUTHOR]