Acta Geographica Sinica ›› 2021, Vol. 76 ›› Issue (9): 2224-2239.doi: 10.11821/dlxb202109013

• Environmental Change and Human Adaptation in Arid Land • Previous Articles     Next Articles

Hydrochemical compositions of natural waters inOrdos Deserts and their influencing factors

REN Xiaozong1(), YANG Xiaoping2()   

  1. 1. School of Geography Science, Taiyuan Normal University, Jinzhong 030619, Shanxi, China
    2. School of Earth Sciences, Zhejiang University, Hangzhou 310027, China
  • Received:2020-06-20 Revised:2021-02-26 Online:2021-09-25 Published:2021-11-25
  • Contact: YANG Xiaoping E-mail:renxzmail@126.com;xpyang@zju.edu.cn
  • Supported by:
    National Natural Science Foundation of China(41672182);Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research(WL2018004);Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(2019L0789);Youth Academic Leader Programs of Taiyuan Normal University

Abstract:

The analysis of hydrochemical compositions of natural waters and their influencing factors is helpful to understand the regional hydrogeological environment and hydrogeochemical development history. The Ordos Deserts, consisting mainly of the Mu Us Sandy Land and the Hobq Sand Sea, are located in the south of Hetao Plain, north to the Great Wall, surrounded by the Yellow River in the west, north and east, and adjacent to the Loess Plateau in the south. The Ordos Deserts make up the Ordos Plateau, with the same tectonic background, similar amount of precipitation and evaporation rates. There are a large number of lakes and rivers in these deserts. In this paper, based on the hydrochemical data of natural waters in the Ordos Deserts, the chemical compositions of natural waters and their influencing factors are analyzed, using various hydrochemical analysis methods. Results show that although Mu Us Sandy Land and Hobq Sand Sea have different landscapes, their natural waters of the same type have similar hydrochemical features, which should be related to their similar rates of evaporation. Deep groundwater in the Ordos Deserts is mainly Ca2+-HCO3- type and its chemical composition is mainly influenced by rock weathering. Due to strong evaporation, the hydrochemical nature of lakes in these regions is characterized with Na+-Cl- contents. As for shallow groundwater and river waters, their hydrochemical features and influencing factors show transitional characteristics between deep groundwater and lake water. The ion ratios show that the weathering of evaporites, carbonate and silicate rocks affects the hydrochemical composition of deep groundwater, shallow groundwater and river water to a varying degree. Although the groundwater and river water in the Ordos Deserts are suitable for irrigation, an excessive use of them will cause salinization, which should be given attention timely.

Key words: Ordos Deserts, natural waters, hydrochemical composition, influencing factor