Hydrogeochemical processes in the groundwater environment of Heihe River Basin, northwest China

Abstract

The Heihe River Basin is a typical arid inland river basin for examining stress on groundwater resources in northwest China. The basin is composed of large volumes of unconsolidated Quaternary sediments of widely differing grain size, and during the past half century, rapid socioeconomic development has created an increased demand for groundwater resources. Understanding the hydrogeochemical processes of groundwater and water quality is important for sustainable development and effective management of groundwater resources in the Heihe River basin. To this end, a total of 30 representative groundwater samples were collected from different wells to monitor the water chemistry of various ions and its quality for irrigation. Chemical analysis shows that water presents a large spatial variability of chemical facies (SO 4 2--HCO 3 -, SO 4 2--Cl -, and Cl --SO 4 2-) as groundwater flow from recharge area to discharge area. The ionic ratio indicates positive correlation between the flowing pairs of parameters: Cl -and Na ? (r = 0.95), SO 4 2-and Na ? (r = 0.84), HCO 3 -and Mg 2? (r = 0.86), and SO 4 2-and Ca 2? (r = 0.91). Dissolution of minerals, such as halite, gypsum, dolomite, silicate, and Mirabilite (Na 2 SO 4 Á10H 2 O) in the sediments results in the Cl -, SO 4 2-, HCO 3 -, Na ? , Ca 2? and Mg 2? content in the groundwater. Other reactions, such as evaporation, ion exchange, and deposition also influence the water composition. The suitability of the groundwater for irrigation was assessed based on the US Salinity Laboratory salinity classification and the Wilcox diagram. The results show that most of the groundwater samples are suitable for irrigation uses barring a few locations in the dessert region in the northern sub-basin.

Assessment of the Hydrogeochemical Processes Affecting Groundwater Quality in the Eocene Limestone Aquifer at the Desert Fringes of El Minia Governorate, Egypt

“…Furthermore, compositional relations among dissolved species can help to reveal the origin of solutes and the processes that generated the observed compositions (Gaofeng et al 2010). The following processes are found to be more effective.…”

Impacts of environmental flow controls on the water table and groundwater chemistry in the Ejina Delta, northwestern China

“…As shown in Fig. 6, the depth of the shallow groundwater table varies from 2 to 4 m, except for the northeastern portion of the basin, where the depth is [4 m. Salt dissolution, deposition, ion exchange, evaporation and other reactions cause groundwater to evolve from a dilute calcium bicarbonate type in recharge areas toward a more concentrated sodium chloride or calcium chloride type (Feng et al 2004;Wen et al 2005;Si et al 2009;Zhu et al 2010). The groundwater TDS has a corresponding relationship with the major ions chemistry; the major ion chemistry in the groundwater generally changes as the groundwater TDS varies (Deutsch 1997).…”

“…Feng et al 2004;Wen et al 2005;Zhang et al 2005;Chen et al 2006;Ma and Edmunds 2006;Su et al 2007Su et al , 2009Si et al 2009;Zhu et al 2010). For example, Feng et al (2004) investigated the distribution and evolution of water chemistry in the Heihe River Basin and concluded that, since the 1960s large volumes of river water diverted for irrigation have re-emerged as springs at the edge of alluvial fans and then flowed into the Heihe River.…”

Using hydrochemical and isotopic data to determine sources of recharge and groundwater evolution in an arid region: a case study in the upper–middle reaches of the Shule River basin, northwestern China

“…HCO 3 -and also a mNa/Cl ratio near 1. This has been observed in many of the neighboring basins in the Hexi Corridor (Chang and Wang 2010;Wang et al 2002), as well as in other inland river basins in northwestern China, such as the Ejina basin (Wang et al 2011;Gaofeng et al 2010).…”