Water use strategies and water conservation in Picea schrenkiana forests in the Kashi River Basin, China

Abstract

Study region

The Kashi River Basin is located in northwestern Xinjiang, China.

Study focus

Using stable isotope techniques and incorporating the MixSIAR model, we studied the main water sources of Picea schrenkiana during the growing season. We estimated the evaporation loss of soil and river water using the Craig-Gordon and Rayleigh Fractionation models, respectively, to compare their evaporation loss and explore the reasons for these differences.

New hydrological insights

The results showed that (1) in spring 2024, Picea schrenkiana mainly utilized 0–60 cm of soil water; the utilization rate of each layer was 20.5 %, 21.0 %, and 20.6 %, respectively; in summer 2024, 0–40 cm of soil water was utilized, with the utilization rate of each layer reaching 25.1 % and 21.1 %, respectively; and in autumn 2024, 0–20 cm of soil water was utilized and the rate rose to 29.6 %. (2) The evaporation loss of soil water was lower than that of river water during the same period. In the summer of 2024, the evaporation loss of river water was 60 %, while the evaporation loss of soil water from 0–20 cm was the largest, only 36.6 %, reflecting the function of Picea schrenkiana forests to contain water. This study provides a reference for vegetation protection and management in the region as well as its ecological benefits.