Elements d'un modele reliant la granulometrie et la mineralogie d'un sol gypso-calcaire a ses proprietes hydriques

National audienc

Coupled model of solute transport simulating and hydraulic properties predicting in gypso-calcareous soil

International audienc

Simulation mathématique et précision d'ajustement des paramètres de transferts

National audienc

Comparaison d'un modele de prevision de la courbe de retention avec des donnees experimentales obtenues sur des sols agreges

National audienc

Monitoring the impact of surface albedo on a saline lake in SW Russia

Lake Elton is located east of the Volga River in Russia and covers an area of 155¿km2. The hydrological system of the Lake and its surroundings are extremely vulnerable to climate change and human interference, but available local and regional information is sparse. Utilising climate data from 1987 to 2009 and surface albedo readings from the MODerate resolution Imaging Spectroradiometer satellite since 2000, this study analyses Lake degradation processes since 2005. Lake surface albedo analysis indicates that during the past 6¿years, lake albedo has increased dramatically from average peak values of 0·14 to 0·40. In addition, air temperature has increased by 2¿°C, and annual precipitation has decreased by 40 per cent. Moreover, human intervention in the area has increased environmental pressure on the Lake, causing a reduction of runoff inflow because of water capture, use of check-dams and water-harvesting systems. The results of the study show that, under current conditions, the Lake surface albedo is likely to remain high as compared with previous observations. The current trend implies an average 2 per cent per year increase in future annual albedo, with a maximum possible increase of 4 per cent up to a steady state of salt-crust albedo value