The Role of New-Emerging Lands on Sources of Aeolian Sand Deposits Driven by Shrinking of the Urmia Salt Lake

Abstract

Urmia Lake, the largest saline lake in Iran and the Middle East, is located in the northwest of Iran, has shrunk over the past decades. The reduced water level has increased the area of dry land around the lake allowing new environmental hazard such as sand dunes encroachment, particularly on the western side of the lake. There are five terrain types that could contribute sediment to the dunes, and it is the main aim of this research to identify the contributions to the dunes of each terrain type. Fifteen surface samples were collected from the five most erodible terrain types and eight samples were collected from the dunes both in downwind and upwind directions from the lake, and major element components were measured using X-ray fluorescence (XRF). According to the Besler classification, all samples are in the saline class. Also, the chemical index of alteration (CIA) values in all samples were less than 50, indicating weak weathering. Based on multivariate statistical analysis, suitable tracers were selected and were imported to the sourcing equations. Quantification of uncertainty and the creation of two new fingerprinting models for aeolian sediments based on both Bayesian and GLUE procedures were used. The highest proportion comes from the salty and puffy lands (44.2%) followed by salty polygon land (23.5%), clay-salty areas, puffy-flaky lands (7.01%), the terminus of the fine sandy alluvial fan (13.2%), and clay-salty abandoned lands (12.1%). It is concluded that if land managers use these results, they can more efficiently decrease the hazards posed by dune reactivation and migration though implementation of soil conservation on the affected lands around the dried lake.

Aeolian Sand Erosion and Deposition Patterns in the Arid Region of the Xiliugou Tributary on the Upper Reaches of the Yellow River

“…By tracking sediment core SSK80/GC2, which had been collected from the Arabian Sea over the past 50 years, Sebastian et al (2023) [4] could infer the aridity of the source area and the strength of the southwest monsoon during the deposition period. In another study, Samani et al (2021) [5] analyzed the extent to which five different geomorphological types of dune sediments contributed to parts of the Urmia salt lake that had dried up. Meanwhile, Chen et al (2022) [6] performed mathematical simulations to map the spatiotemporal distribution of dust emissions in the Aral Sea region and trace the process of dust migration and sedimentation.…”