| Abstract: | Dry regions of the world, that is, hyper‐arid to subhumid regions that are mostly warm to hot and so‐called ‘drylands’, cover almost 50% of the total land area. They are inhabited by human populations that are approaching one billion worldwide. Despite low rainfall levels, dry regions have some of the world’s largest lakes and reservoirs. They also have the widest variety of standing water types that include permanent freshwater lakes and reservoirs, temporary freshwater lakes, and permanent and temporary saline lakes. Many characteristics of these waters are different from waters in temperate, better‐watered areas, upon which most limnological knowledge is based. Notwithstanding many economic, scientific, ecological and other values, lakes in drylands are subject to extensive and intensive anthropogenic impacts. Included are almost all those affecting lakes in temperate, tropical and subtropical regions, as well as some impacts more or less confined to dryland lakes, especially salinization. These anthropogenic impacts and their importance have not been fully recognized at national and international levels. |
