Journal metrics

Journal metrics

  • IF value: 4.256 IF 4.256
  • IF 5-year value: 4.819 IF 5-year 4.819
  • CiteScore value: 4.10 CiteScore 4.10
  • SNIP value: 1.412 SNIP 1.412
  • SJR value: 2.023 SJR 2.023
  • IPP value: 3.97 IPP 3.97
  • h5-index value: 58 h5-index 58
  • Scimago H index value: 99 Scimago H index 99
Volume 22, issue 6 | Copyright
Hydrol. Earth Syst. Sci., 22, 3473-3491, 2018
https://doi.org/10.5194/hess-22-3473-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.

Research article 28 Jun 2018

Research article | 28 Jun 2018

Delineating multiple salinization processes in a coastal plain aquifer, northern China: hydrochemical and isotopic evidence

Dongmei Han1,2 and Matthew J. Currell3 Dongmei Han and Matthew J. Currell
  • 1Key Laboratory of Water Cycle & Related Land Surface Processes, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, 100101, China
  • 2College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 100049, China
  • 3School of Engineering, RMIT University, Melbourne VIC 3000, Australia

Abstract. Groundwater is an important water resource for agricultural irrigation and urban and industrial utilization in the coastal regions of northern China. In the past 5 decades, coastal groundwater salinization in the Yang–Dai river plain has become increasingly serious under the influence of anthropogenic activities and climatic change. It is pivotal for the scientific management of coastal water resources to accurately understand groundwater salinization processes and their causative factors. Hydrochemical (major ion and trace element) and stable isotopic (δ18O and δ2H) analysis of different water bodies (surface water, groundwater, geothermal water and seawater) were conducted to improve understanding of groundwater salinization processes in the plain's Quaternary aquifer. Saltwater intrusion due to intensive groundwater pumping is a major process, either by vertical infiltration along riverbeds which convey saline surface water inland, and/or direct subsurface lateral inflow. Trends in salinity with depth indicate that the former may be more important than previously assumed. The proportion of seawater in groundwater is estimated to have reached up to 13% in shallow groundwater of a local well field. End-member mixing calculations also indicate that the geothermal water with high total dissolved solids (up to 10.6gL−1) with depleted stable isotope compositions and elevated strontium concentrations (>10mgL−1) also mixes locally with water in the overlying Quaternary aquifers. This is particularly evident in samples with elevated SrCl ratios (>0.005 mass ratio). Deterioration of groundwater quality by salinization is also clearly exacerbated by anthropogenic pollution. Nitrate contamination via intrusion of heavily polluted marine water is evident locally (e.g., in the Zaoyuan well field); however, more widespread nitrate contamination due to other local sources such as fertilizers and/or domestic wastewater is evident on the basis of NO3Cl ratios. This study provides an example of how multiple geochemical indicators can delineate different salinization processes and guide future water management practices in a densely populated water-stressed coastal region.

Download & links
Publications Copernicus
Download
Short summary
Based on hydrochemical and isotopic analysis, we investigated the potential hydrogeological processes responsible for the increasing groundwater salinity in the coastal aquifer of Yang–Dai River coastal plain, northern China. Seawater intrusion is the major aspect and can be caused by vertical infiltration along the riverbed at the downstream areas, and lateral inflow into fresh aquifer. Geothermal water also makes a significant contribution to increasing the groundwater salinity.
Based on hydrochemical and isotopic analysis, we investigated the potential hydrogeological...
Citation
Share