Taking the Yangtze River Source Basin (YRSB) and Shule River Basin (SRB) as two typical cases, the sustainability of the water resources in these two basins was evaluated using the level of water stress (LWS) from sustainable development goal 6.4.2, and the regulating effect of the glacier runoff on the LWS was quantified. From 2000 to 2030, the level of socioeconomic development in the YRSB is low, and the total water consumption is only about 0.18 x 10(8) m(3), whereas the SRB has a relatively high level of socioeconomic development and total water consumption is about 10 x 10(8) m(3), i.e., 50 times higher than that in the YRSB. For the aforementioned reasons, the SRB's LWS is much higher than the YRSB's, resulting in a very low sustainability of water resources. As natural assets, glaciers flow downstream in the runoff mode, so compensation at the watershed scale should be considered. In the basin, the optimal allocation of water resources is needed. At the inter-basin scale, the compensation mechanism of glacier water resources needs to be improved.

Study region: The Shule River Basin (SRB) in northwestern China is a representative area of global glacier-covered arid areas. Study focus: Water resources have greatly influenced sustainable development in global arid re-gions where glacier runoff is an important component of water resource supply. This study focused on the assessment of the water resources-carrying capacity in the SRB based on the United Nations Sustainable Development Goals (SDGs) indicator 6.4.2, level of water stress (LWS). New hydrological insights for the region: During the period between 2000 and 2030, the runoff of the SRB was predicted to follow an overall increasing trend. From 2000 to 2020, the annual average runoff in the upper reaches of the SRB was 10.9 x 10(8) m(3), and then from 2021 to 2030, it increased by 22.8 %. According this trend, the average contribution of glacier meltwater to the total basin runoff is expected to decrease from the current 23 % to 15 % by 2030 (Representative Concentration Pathway 2.6, RCP 2.6). The supply of fresh-water resources has been close to the level of demand since 2015 and the LWS may increase between 2021 and 2030. The existence of glacial meltwater is expected to result in the continued reduction of basin water stress in the SRB by an average of 0.71 during the period between 2000 and 2030. Therefore, it is necessary to control water consumption of the socioeconomic system and adjust the industrial structure to face or adapt to the crisis of water shortage in global glacier-covered arid areas.