Research on the Hydrochemical Characteristics of Groundwater at the Southern Edge of Taklimakan Desert and along the Southern Desert Highway, China

Abstract In this paper, the characteristics of chemical components of groundwater were analyzed by means of investigating and collecting groundwater samples and hydrochemical analyses in the lower reaches of Niya river, Yatonggusi river and Andier river, the south edge of Taklimakan desert and along the southern desert highway in Tarim basin. It indicates that the total dissolved solids (TDS) in shallow groundwater are respectively 2.14-4.97g•L-1, 5.79-7.71g•L- 1 and 1.21-38.85g•L-1 in Niya river, Yatonggusi river and Andier river. The partial correlationships of groundwater TDS with HCO3-, SO42-, Cl-, and Na+ ions are extremely obvious, the relative coefficients ranging from 0.9598 to 0.9874, and quite obvious to Mg2+, Ca2+ ions with the coefficients of 0.8508 and 0.7771 in the lower reaches of Andier river. For the groundwater TDS along the southern desert highway, its partial correlationships to SO42-, HCO3- and Cl- ions are extremely obvious, with the relative coefficients ranging from 0.9171 to 0.9686, and quite obvious to Na+ and Ca2+ ions with the coefficients of 0.7873 and 0.6322. In the lower reaches of Andier river, there are some spatial correlations on the aspects of K+ and HCO3- contents in groundwater, and the spatial correlation distances in latitude and longitude are 0.03° and 0.21°. Based on the established semivariogram models, isograms of the distribution of ion contents in groundwater were plotted by using Kriging and IDW methods. The results show that the spatial distribution characteristics of chemical components in groundwater are consistent with that of ions contents changing along the latitude from south to north.