Physico-Chemical Composition of Saline Lakes of the Gobi Desert Region, Western Mongolia

Abstract

Mongolian saline lakes have been rarely studied. In particular, physicochemical composition of small shallow lakes of the Gobi Desertregion in western Mongolia is simply unknown. Objectives were to characterize chemical composition and describe biogeochemical characteristics of saline lakes in the Gobi Desertregions and steppe mountains, with an emphasis on environmental parameters associated with heavy metal ions. Major physicochemical parameters were determined in 14 lakes (with varying degrees of salinity) located in western Mongolia and associations with geographic variation and distance were determined. Vertical profiles for temperature, specific conductance, and dissolved oxygen were characterized. Salinity and pH were measured with multiparameter submersible profilers. Heavy metal ions (i.e., As, Pb, and Cd) and microelements (i.e., K, Na, Zn, Cu, Ni, Cr, and Co) were analyzed with Inductively Coupled Plasma-Mass Spectrometry. Hydrogen sulfide, ammonia, nitrite, and nitrate were also determined by commercial kits for elemental analysis. Overall, 43 environmental parameters were determined from 31 water samples from various locations, representing distinct geographic features, including Gobi Desert, mountain range and steppe area. Several of these lakes had harmful concentrations of arsenate (< 0.34 mg/L). Heavy metal concentrations were correlated with selected physico-chemical variables of lake salinity and geographic specificity. We inferred that various environmental features, in addition to environmental pollution and mining activity, may be responsible for increased heavy metal concentrations in the Gobi Desert of the western Mongolia. The outcome of this study not only provided insights into lake chemistry, but should also be valuable for water resource management to mitigate potential poisoning and improve public health.

A Large-Scale Survey of the Bacterial Communities in Lakes of Western Mongolia with Varying Salinity Regimes

“…For each lake and depth, both physical and chemical parameters were measured as described previously [30,31]. In brief, temperature, dissolved oxygen, pH, and salinity were measured using a Hanna HI 9828 multiparameter meter (Hanna Instruments, Woonsocket, RI, USA).…”

“…Therefore, lakes in this region have remained relatively untouched from scientific and anthropogenic activity, making them an excellent research environment to explore diversity in high-latitude saline environments and perform a comparative analysis of microbial community compositions. In recent years, anthropogenic activity-especially mining-coupled with global warming has increased the average temperature in the region by 3 to 5 • C. Recent studies have profiled the chemical compositions of 18 saline lakes in western Mongolia [30,31]. However, the microbial community composition of these lakes remains elusive.…”

Heavy metal pollution characteristics and health risk assessment of dust fall related to industrial activities in desert steppes

“…Desert steppe ecological security issues are a source of debate and the focus of an ongoing study on heavy metal pollution in desert steppe dust ( Bayanmunkh et al, 2017 ; Zhao et al, 2012b ). Because of the desert steppe’s unique geographical location, heavy metals in dust are easily re-distributed and enter the human body via hand-oral ingestion, skin contact, and inhalation, and can cause adverse health effects ( Ewers, 1991 ; Atiemo et al, 2011 ; Wei et al, 2010a , 2010b ; Wei et al, 2015 ).…”