Assessment of water retention dynamic in water resource formation area: A case study of the northern slope of the Qinling Mountains in China

Abstract

Study Region: The northern slope of Qinling Mountains (NQL) is an important water retention (WR) area in China, which guarantees the utilization of water resources in the plain area. However, the effects of significant changes in climate and land cover on WR have not been quantitatively studied in recent years. Study Focus: In this study, we quantified the relative impacts of climate and land cover changes on WR at NQL and predicted the future changes of WR under different climate scenarios (SSP2–4.5 and SSP5–8.5). New Hydrological Insights for the Region: The results indicated that WR in NQL has exhibited an overall increase from 1985 to 2020 at a rate of 1.10 mm/a, with climate and land cover change explaining 86.3 % and 13.7 % of this change, respectively. Although precipitation has increased since 1998, the compounding effects of land cover change and precipitation intensity increase have led to a slight decline of WR magnitude and efficiency due to their offsetting impacts. Under future climate change, the WR capacity changes in the SSP2–4.5 are relatively stable, while the significant increase in temperature under the SSP5–8.5 lead to a decreasing trend in WR efficiency. In addition, we proposed an indicator framework to evaluate WR using WR efficiency and baseflow lag time. Our results may provide valuable insights for sustainable utilization and scientific management of water resources.

Keywords

• Water retention
• Climate change
• Land cover
• Future prediction
• Indicator framework
• Baseflow lag time