Salt Lakes

Abstract

Salt lakes are widespread and are found under a range of conditions, including cold and hot temperatures. They are, however, mostly confined to semi-arid to arid regions where evaporation exceeds precipitation. They are generally permanent or temporary bodies of water with salinities greater than 3 g L⁻¹ and lacking any recent connection to the marine environment. The salinity level used to demarcate them from freshwater lakes is somewhat arbitrary, given the large variation in salinity that can occur in many lakes. Many salt lakes can be dry seasonally or for longer periods and exhibit dry saline lake beds, and even hypersaline conditions with salt crusts across the surface. Salt lakes support biota that have physiological and biochemical mechanisms that enable them to tolerate high salt levels, and are highly sensitive to even small changes in the climate. The most conspicuous invertebrate animals are crustaceans, although a variety of other non-crustacean groups also occur. The vertebrates of saline lakes comprise mainly fish and birds. Many salt lakes have been degraded as a consequence of human activities especially from the construction of dams and diversion of surface inflows, increased salinization, and other catchment activities, such as mining, pollution, the introduction of 205 exotic species, and human-induced climate change.