Introducing Pampean Lakes
摘要
The Pampa plain is an extensive lowland of 600,000 km2 in central Argentina. To the north is transitional toward the Chaco and in the south, into northern Patagonia. It contains the most extensive aeolian record of the Southern Hemisphere, including loess and loess like deposits. The flat relief favours the development of numerous lakes and wetlands. There are 13,824 lakes greater than 10 ha, and 146,000 between 0.05 and 10 ha, formed by aeolian, tectonic and marine processes. Lakes exhibit a substantial hydrological variability controlled by the South American Summer Monsoon System. Since the 1970’s a hyper-wet phase occurred, being the largest precipitation increase in the world continental regions. Paleoclimate reconstructions based on paleoliminological data allow to infer a regional hydroclimatic variability since the Last Glacial Maximum up to the last two millennia. Pampean lakes are effective sentinels of global change as they respond sensitively to regional hydroclimate changes, as well as to land-use and land-cover changes. Pampa plain is a particular site since limnological studies started as early as the end of the eighteenth century. Paleolimnological research has significantly risen in the latter half of the twentieth century and the beginning of the twenty-first.