A technical framework for determining water consumption thresholds in the semi-arid Xiliao River Plain based on terrestrial water balance

The Xiliao River Plain. This study proposed a technical framework for determining water consumption thresholds in semi-arid regions based on terrestrial water balance. The technical framework includes three parts: adaptability evaluation and selection of remote sensing products, calculation of agricultural and ecological water consumption, and determination of water consumption thresholds. This framework could separate agricultural and ecological water consumption, and effectively determining the water consumption thresholds. During the period of 1980–2022, agricultural water consumption increased significantly ( p < 0.01) at the rate of 0.67 × 10 8 m 3 /year, but ecological water consumption decreased significantly ( p < 0.05) at the rate of 0.20 × 10 8 m 3 /year. According to the type of major water-consuming sectors, the Xiliao River Plain was categorized into three types of regions: regions where agricultural water consumption accounted for the majority (AR), regions where ecological water consumption accounted for the majority (ER), and regions where agricultural and ecological water consumption together accounted for the majority (AER). For all three types of regions, a significant positive linear correlation between precipitation surplus coefficient and terrestrial water storage change was detected. To maintain terrestrial water balance, the proportion of total evapotranspiration consumption to precipitation should be limited to 76.3∼93.5 %. For AR, ER and AER, the proportion of major water-consuming sectors in precipitation should be controlled at 47.3∼63.1 %, 49.9∼62.7 % and 61.8∼80.0 %, respectively. • Determining water consumption thresholds in semi-arid regions using terrestrial water balance. • Agricultural and ecological water consumption were separated according to evapotranspiration and land use. • A new indicator, precipitation surplus coefficient, was proposed to quantify water consumption thresholds.