Lake Urmia Salt lake's sedimentation and water dynamics impacts on past environmental reconstruction

E. Gibert (1) , Alina Tudryn (1) , Ting Kong (1) , Piotr Tucholka (1, 2) , Seyed-Hani Motavalli-Anbaran (3) , Christelle Marlin (1) , Mohammad Lankarani (4) , Hesam Ahmady-Birgani (3)

1 GEOPS - Géosciences Paris Saclay
2 UW - University of Warsaw
3 University of Tehran
4 Urmia University

In recent decades, an overall decrease in surface water resources, even saline, especially in semi-arid and arid regions of the world, can be both a precursor to a decrease in groundwater recharge. This decrease comes either from the impact of climate change moving towards a different distribution of precipitation and evapotranspiration indices, and/or from the increasing footprint of anthropogenic activities both through inappropriate water use, extensive pumping, or even population increases in areas already under pressure for freshwater resources (e.g., Wurtsbaugh et al., 2017; Wang et al., 2018). This is particularly pregnant in salt lake basins for which water resources are vital to hydro-ecosystems and the population. But these basins are not easy to study other than by modeling, due to their very complicated structures as well as the processes they undergo (saltwater intrusion, pollution, etc.), and considering the lacustrine sedimentary deposits (degradation) to which they may or may not be connected. Here we present ongoing research on the Urmia Lake Basin (northern Iran) which is facing a drastic decrease of more than 8 m in its water level over the last 20 years, leading to soil salinization, increase in dust storms, decline in ecosystem services with the effect of losses in agricultural production and massive emigration of rural communities. In order to understand the hydrogeological behavior of the lake under anthropogenic pressures (excessive pumping) and climate change, sedimentary sequences were recovered from the recently drained western part of Urmia Salt Lake, as well as surface and groundwater samples and geological samples from the entire Shahr Chay River Basin.

Domaines: Interfaces continentales, environnement

E. Gibert, Alina Tudryn, Ting Kong, Piotr Tucholka, Seyed-Hani Motavalli-Anbaran, et al.. Lake Urmia Salt lake's sedimentation and water dynamics impacts on past environmental reconstruction. 7ème édition du colloque "Climat et Impacts" 2022, Nov 2022, Gif-sur-Yvette, France. ⟨hal-03874535⟩