This study presents a multi-disciplinary approach for investigating the interactions between groundwater and surface water in the semi-arid Hailiutu catchment in the Erdos Plateau, Northwest China. The study consists of statistical detection of river flow regime shifts at the basin level; multiple in-situ measurements for quantifying groundwater discharges using hydraulic, hydrochemical and temperature methods at a local scale; analysis and simulation of impacts of different land use scenarios on groundwater and surface water interactions at the sub-catchment scale; and the quantification of temporal and spatial groundwater and surface water interactions with hydrochemical tracers and modelling methods at the basin scale.
The study found that the river flow consists of mainly groundwater discharges at all scales. The river flow regime has been intensively altered by human activities, such as the construction of reservoirs, water diversion, groundwater exploitation, and reforestation. Water use by plants and crops consumes majority of the precipitation. Groundwater sustains vegetation growth and feeds river discharges. The water resources and ecosystem management priority should reduce evaporative water uses by promoting dry resistant plant species for vegetating sand dunes and lower irrigation demand crops for socio-economic development. Furthermore, the Hailiutu River catchment must manage the groundwater recharge for water resource conservation and the maintenance of healthy ecosystems.
Table of Contents
1.2 Research objectives and approach
1.3 Innovation and challenge
1.4 Thesis outline
2. The flow regime shift in Hailiutu River
2.2 Material and methods
2.3 Results and discussion
3. A multi-method approach to quantify groundwater/surface water interactions
3.2 Material and methods
3.3 Results and discussion
4. Groundwater-surface water interactions under different land use scenarios
4.2 Materials and methods
5. Groundwater and surface water interactions and impacts of human activities in the Hailiutu Catchment, Northwest China
5.2 Materials and methods
6 Conclusions, outlook and future research
6.2 Outlook and future research
Zhi Yang was born in 1974 in Anhui Province, China. He graduated from the Hefei University of Technology, China with a BSc degree in Environmental Engineering in 1996. He participated in the MSc programme Hydrology and Water Resources from 2002 to 2004 at UNESCO-IHE, Delft, The Netherlands. In December 2009, he entered the PhD programme at UNESCO-IHE (now called IHE Delft) in cooperation with China University of Geosciences (Beijing). He is working at the Institute of the Huai River Water Resources Protection as an environmental impact assessment consultant.