Comparison of Lakes with Hypersaline, Heliothermic, sub-surface Oxygen Maxima

The data set is a comparison of Meromictic Lakes which exhibit at least few characteristics among hyper-salinity, sub-surface temperature maxima (heliothermic) ,sub-surface oxygen maxima(metalimnitic) and oxygen supersaturation. Very few such lakes are reported so far with about thirty (30) lakes world wide which are meromictic and heliothermic. . Meromictic lakes are highly stratified which exhibit meromixis, a condition in which a lake does not mix completely. Nine such lakes are reported in Asia and this data reports first time from India, Pulicat lake which has all these characteristics. Interestingly, the embedded meromixis still sustains some species withstanding the large ranges of temperature and salinity in this region of Pulicat. the Pulicat Lake in southern India that attracts various aquatic, migratory birds like Greater & Lesser Flamingoes, Pelicans, Terns, Teals, Grey heron, Open Bill Stork, Black-Headed Ibis, spot-Billed ducks, painted stork and little Egret. The lake is a habitat 88 species of birds which include more than 5 endangered and threatened species. The salinity of the lagoon is extremely fluctuating, shifting regimes from fresh to hypersaline on seasonal scales. recording a maximum of 191 ppt. Such high salinity in the Pulicat have so far not been reported.