School of Environmental Science and Engineering, Southern University of Science and Technology, 1088 Xueyuan Avenue, Shenzhen, 518055, China.
School of Water Resources and Hydropower Engineering, Wuhan University, Wuhan, 430072, China.
Environ Geochem Health. 2020 Mar;42(3):933-953. doi: 10.1007/s10653-019-00406-3. Epub 2019 Sep 7.
Water resource assessment is crucial for human well-being and ecosystem health. Assessments considering both blue and green water are of great significance, as green water plays a critical but often ignored role in the terrestrial ecosystem, especially in arid and semi-arid regions. Many approaches have been developed for green and blue water valuation; however, few approaches consider the interrelationship between green and blue water. This study proposed a new framework for green and blue water assessment by considering the interactions between green and blue water and the connections between human and natural ecosystems in an arid endorheic river basin where hydrological cycling is dramatically altered by human activities. The results show that even though green water is the dominant water resource, blue water is also critical. Most of the blue water is redirected back into the soil through physical and human-induced processes to meet the water demand of the ecosystem. The blue and green water regimes are found to be totally different in different ecosystems due to the temporal and spatial variability in water supply and consumption. We also found that humans are using an increasing proportion of water, resulting in decreasing water availability. Extensive water use by humans reduces the water availability for the natural ecosystem. Approximately 38.6% of the vegetation-covered area, which is dominated by farmland and forest, may face a moderate or high risk of increased conflict and tension over freshwater. This study provides crucial information to better understand the interactions between green and blue water and the relations between humans and nature by explicitly assessing water resources. It also provides crucial information for water management strategies that aim to balance humankind and nature.
水资源评估对于人类福祉和生态系统健康至关重要。考虑到蓝水和绿水的评估意义重大，因为绿水在陆地生态系统中起着至关重要但经常被忽视的作用，尤其是在干旱和半干旱地区。已经开发了许多用于评估绿水和蓝水的方法；然而，很少有方法考虑绿水和蓝水之间的相互关系。本研究提出了一个新的框架，用于评估绿水和蓝水，考虑了绿水资源和蓝水资源之间的相互作用，以及人类和自然生态系统之间的联系，在一个受到人类活动极大影响的干旱内陆河流域中，水文循环发生了显著变化。研究结果表明，尽管绿水是主要的水资源，但蓝水也同样重要。大部分蓝水通过物理和人为过程重新回流到土壤中，以满足生态系统的水需求。由于供水和消耗在时间和空间上的变化，不同生态系统中的蓝水和绿水状况存在显著差异。我们还发现，人类正在使用越来越多的水资源，导致水资源的可利用量减少。人类的广泛用水减少了自然生态系统的水资源可利用量。大约 38.6%的植被覆盖区（主要是农田和森林）可能面临因淡水资源而加剧冲突和紧张的中度或高度风险。本研究通过明确评估水资源，提供了关于绿水资源和蓝水资源之间相互作用以及人类与自然之间关系的关键信息。它还为旨在平衡人类和自然的水资源管理策略提供了关键信息。
