Arid Zone Research ›› 2025, Vol. 42 ›› Issue (10): 1860-1875.doi: 10.13866/j.azr.2025.10.10

• Plant Ecology • Previous Articles     Next Articles

Estimation of ecological water requirements for natural vegetation in the Tarim River Basin under climate change using CMIP6

HUANG Mianting1,2(), MU Zhenxia1,2(), YANG Rongqin1,2, ZHAO Shikang1,2, LI Zilong1,2   

  1. 1. College of Hydraulic and Civil Engineering, Xinjiang Agricultural University, Urumqi 830052, Xinjiang, China
    2. Xinjiang Key Laboratory of Hydraulic Engineering Security and Water Disasters Prevention, Urumqi 830052, Xinjiang, China
  • Received:2025-02-08 Revised:2025-04-30 Online:2025-10-15 Published:2025-10-22
  • Contact: MU Zhenxia E-mail:320222324@xjau.edu.cn;xjmzx@xjau.edu.cn

Abstract:

To adapt to or mitigate the effects of climate change on the water resource demands of terrestrial ecosystems, it is crucial to determine the vegetation ecological water requirements (EWR) under changing climate conditions for maintaining the stability of terrestrial ecosystems. This study used CMIP6 climate model data and integrated the RF, XGBoost, ANN, and LSTM models along with meteorological and remote sensing factors to design various input combinations. Furthermore, an in-depth analysis of each model’s performance was performed under different input configurations for EWR prediction in the Tarim River Basin. Based on this analysis, the optimal model was selected to predict future EWR, and the SHAP method was applied to quantify the contributions of meteorological and remote sensing factors to EWR changes. The results were as follows: (1) All four machine learning models were suitable for evaluating EWR in the study area, with the XGBoost model demonstrating the best overall performance. Temperature and net radiation were the primary meteorological factors influencing the model’s predictions, and the incorporation of remote sensing factors further enhanced the model’s performance. (2) The average EWR under the historical, SSP2-4.5, and SSP5-8.5 scenarios was 498.58×108 m3, 548.81×108 m3, and 570.28×108 m3, respectively, showing an overall upward trend in future EWR. April and May were the periods with the most significant increases in water demand. (3) Spatially, the EWR in the study area under all three scenarios exhibited a distribution pattern of higher values in the north and lower values in the south. However, under the SSP5-8.5 scenario, the changes in EWR were more pronounced, and the north-south differences became significantly smaller. (4) The main factors influencing EWR changes were leaf area index, net radiation, and minimum temperature, with considerable impact of terrain variation. In plain areas, the leaf area index was the dominant factor driving EWR changes, whereas in mountainous regions, EWR was influenced by a combination of leaf area index, net radiation, and minimum temperature.

Key words: ecological water requirement, XGBoost, CMIP6, machine learning, Tarim River Basin