Hydrochemistry Characteristics of Groundwater in Agricultural Oasis Areas, Northwest China

Abstract

Hydrochemistry of groundwater provides new insight to studying on water evolution in arid and semi-arid regions. The chemical properties of sixty-three groundwater samples were assessed from oasis areas in the middle reaches of Heihe River Basin of northwest China, with the aiming of evaluating natural and anthropogenic factors controlling groundwater quality. Results of the study showed that: The 55.6% groundwater samples were nonsalinized whereas 33.3% slightly salinized and 11.1% moderately salinized existed. The major ions of the groundwater were dominated by Na + , Ca 2+ , HCO 3-, SO 4 2-, and Cl-. The 34.9% of the samples showed NO 3 more than the human affected value. The major anthropogenic inputs into the groundwater contain nitrate, phosphate, potassium and chloride, with Cland NO 3-, which were the major contributors to groundwater pollution resources in the study area. Elevated knowledge of geochemical evolution of groundwater in agricultural oasis areas of northwest China could generally improve understanding of hydro-chemical systems in arid and semi-arid regions of China; further maintain sustainable development and effective management of groundwater resource.

Hydrochemical characteristics and ion sources of river water in the upstream of the Shiyang River, China

“…According to Gibbs model, the sources of ions in river mainly come from rock weathering. In order to explore the main types and chemical composition of weathered rocks, the method of molar ion concentration (mmol• L -1 ) ratio method proposed by Gaillardet was used [41][42][43][44][45]. In conjunction with Table 2, Figure 7 is obtained by Origin 2018 software and the data of all samples.…”