Research on the sustainable utilization of water resources in the Yellow River Basin based on water resources ecological footprint

The Yellow River Basin confronts issues of water scarcity and uneven distribution between upstream and downstream regions. To ensure sustainable water use within the regions, a scientific evaluation of water resource sustainability in the basin is urgently required. Based on the water resource data from the Yellow River Basin in 2020, a water resources ecological footprint evaluation system was developed, incorporating virtual water consumption and reclaimed water utilization. This system comprehensively assessed the sustainable development of water resources in the basin, considering the factors such as water resources ecological surplus/deficit, water resources ecological footprint per 10 000 yuan GDP, and water ecological pressure. The results demonstrated significant regional disparities in per capita water resources ecological footprint across the cities (prefectures) in the Yellow River Basin. Upstream regions generally exhibited higher values, with Bayan Nur of Inner Mongolia, and Hainan Tibetan Autonomous Prefecture and Haibei Tibetan Autonomous Prefecture of Qinghai (10.52, 8.72, 6.85 hm²/person) ranking among the top three. Conversely, economically prosperous and densely populated provincial capitals in the midstream and downstream regions, such as Zhengzhou, Taiyuan, and Xi'an (0.45, 0.35, 0.29 hm²/person), exhibited lower values. Both the areas with the highest and lowest per capita water resources ecological carrying capacity were located in the upstream region. Aba Tibetan and Qiang Autonomous Prefecture of Sichuan, Garzê Tibetan Autonomous Prefecture of Sichuan, and Guoluo Tibetan Autonomous Prefecture of Qinghai (96.29, 79.52, 66.86 hm²/person) ranked among the top three, while Baiyin of Gansu, Wuhai of Inner Mongolia, and Shizuishan of Ningxia (0.002 0, 0.002 5, 0.003 1 hm²/person) exhibited relatively lower values, exhibiting distinct characteristics from the ecological footprint. In terms of per capita water resources ecological surplus/deficit in the basin, only Qinghai and Sichuan in the uppermost reaches showed a surplus. Approximately 85.5% of the cities (prefectures) in other provinces (autonomous regions) were in a deficit state, with water resource pressure indices greater than 1, indicating unsustainable water use and a low level of security. The ecological footprint of water resources per 10 000 yuan of GDP in the basin showed a great difference, with a downward trend from upstream to downstream, and was 1.17, 0.91, 0.68, 0.61, 0.58, 0.28, 0.28, 0.32 and 0.36 hm²/(10 000 yuan) in Qinghai, Sichuan, Gansu, Ningxia, Inner Mongolia, Shaanxi, Shanxi, Henan and Shandong, respectively. It indicates that the water resources utilization efficiency is relatively high in the midstream and downstream provinces (autonomous regions). The study reveals that the ecological deficit of water resources in the Yellow River Basin has significantly surpassed its carrying capacity, necessitating the reinforcement of water resources ecological compensation and sustainable utilization research. Effective measures should be implemented to achieve sustainable support for water resources for economic and social development.