Ecology-oriented groundwater resource assessment in the Tuwei River watershed, Shaanxi Province, China

• Published in: Hydrogeology journal 2016-12, Vol.24 (8), p.1939-1952
• Main Authors: Yang, Z. Y., Wang, W.K., Wang, Z., Jiang, G. H., Li, W. L.
• Format: Article
• Language: English
• Subjects: Aquatic Pollution; Arid regions; Arid zones; Assessments; Base flow; Desertification; Earth and Environmental Science; Earth Sciences; Ecological monitoring; Ecology; Environmental assessment; Environmental conditions; Environmental effects; Freshwater; Geology; Geophysics/Geodesy; Groundwater; Hydrogeology; Hydrology; Hydrology/Water Resources; Lithology; Rivers; Salinization; Semiarid lands; Soil salinity; Surface water; Sustainable use; Total dissolved solids; Vadose water; Waste Water Technology; Water depth; Water Management; Water Pollution Control; Water Quality/Water Pollution; Water resources; Water table; Watersheds
• ISSN: 1431-2174; 1435-0157
• DOI: 10.1007/s10040-016-1446-3

In arid and semi-arid regions, a close relationship exists between groundwater and supergene eco-environmental issues such as swampiness, soil salinization, desertification, vegetation degradation, reduction of stream base flow, and disappearance of lakes and wetlands. When the maximum allowable withdrawal of groundwater (AWG) is assessed, an ecology-oriented regional groundwater resource assessment (RGRA) method should be used. In this study, a hierarchical assessment index system of the supergene eco-environment was established based on field survey data and analysis of the supergene eco-environment factors influenced by groundwater in the Tuwei River watershed, Shaanxi Province, China. The assessment system comprised 11 indices, including geomorphological type, lithology and structure of the vadose zone, depth of the water table (DWT), total dissolved solids content of groundwater, etc. Weights for all indices were calculated using an analytical hierarchy process. Then, the current eco-environmental conditions were assessed using fuzzy comprehensive evaluation (FCE). Under the imposed constraints, and using both the assessment results on the current eco-environment situation and the ecological constraint of DWT (1.5–5.0 m), the maximum AWG (0.408 × 10 8 m 3 /a or 24.29 % of the river base flow) was determined. This was achieved by combining the groundwater resource assessment with the supergene eco-environmental assessment based on FCE. If the maximum AWG is exceeded in a watershed, the eco-environment will gradually deteriorate and produce negative environmental effects. The ecology-oriented maximum AWG can be determined by the ecology-oriented RGRA method, and thus sustainable groundwater use in similar watersheds in other arid and semi-arid regions can be achieved.