Are wetlands freshwaters?

Abstract

Limnology and wetland ecology are intimately related because in both, wateris an essential factor. Despite this, wetlands are water-dependent ecosystems that areneither terrestrial nor aquatic ones. Unlike aquatic ecosystems, they have soils but theyalso have standing water, so they are not truly terrestrial. For this reason, somelimnologists have historically considered that wetlands were an object of study forterrestrial ecologists and viceversa. The International Convention on Wetlands itselfadopted an enumerative definition of wetlands that includes purely aquatic ecosystems,thus leading to further confusion around the wetland concept. Key environmentalfactors controlling wetlands include geomorphic setting, soil properties, fire frequency,hydroperiod, and water sources. In this context, Brinson´s functional wetlandclassification based on hydrogeomorphic aspects was used in the regionalisation ofArgentinean wetlands, which included a Patagonian region with three continentalwetland subregions: 1) Lakes, watercourses and mallines of the Patagonian Andes; 2)Lagunas and vegas of the extra-Andean Patagonia; and 3) Mallines and turberas ofAustral Patagonia and South Atlantic Islands. Wetlands of the Chilean Patagonia aresimilar to those of the Argentinean sector, though some peculiar wetland types such asñadis and cátricos are also found. Wetlands have been and continue to be part of manyhuman cultures in the world. These ecosystems are among the most important in theworld since they provide approximately 40% of all ecosystems contributions to people.Although these nature contributions to people are particularly important in Patagonia(e.g., freshwater sources, forage for livestock, carbon sinks, habitat for biodiversity,etc.) continental wetlands as well as aquatic ecosystems in this region are facing manythreats due to changes in land use associated with global change. Therefore, urge thenecessity of public politics focused on their conservation and sustainable use.