Baseflow characteristics and drivers in headwater catchment of the Yellow River, Tibetan Plateau

Abstract

Study area: The headwater catchment of the Yellow River (HCYR) (95°90′–103°42′E, 32°16′–36°13′N) is located on the northeast of the Tibetan Plateau, a presentative high-cold region catchment, China. Study focus: HCYR serves as the primary water supply during the dry season in downstream of the Yellow River Basin. Herein, we applied linear regression and the Bernaola-Galvan heuristic segmentation algorithm to identify the baseflow trends and abrupt changes. Four baseflow signatures (baseflow index (BFI), seasonal ratio (SR), concave index (CI), and slope of baseflow duration curve (SBDC)) were used to investigate the characteristics of baseflow changes and the drivers quantitatively. New hydrological insights for the region: The main findings are: (1) the baseflow generally exhibited an increasing trend (R2 > 0.35, p < 0.1), (2) baseflow variation has an apparent spatiality, and it shows a more pronounced change in the middle part than the upper and lower parts, and (3) precipitation, sunshine hours, soil moisture and evapotranspiration were the controlling factors on the baseflow characteristics. These findings provide a deeper insight into baseflow behavior and drivers in high-cold regions, which are vital for ecosystem health, water resource safety and management in critical headwater catchments.

Keywords

• Baseflow
• Headwater catchment
• Climate change
• The Yellow River Basin