Water Eco-Function Zoning in China Based on Water Footprints

Water resources are the basic elements of ecological environments, the indispensable basis for our survival, and the key to sustainable socioeconomic development. In the wake of population growth and development, the demand-supply imbalance of global water resources has become serious, and water shortages have become an important limiting factor for the sustainable development of many nations. Water shortages, water pollution, floods and water-logging disasters have threatened and restricted sustainable development and so it is necessary to evaluate the water resources management concept. Water footprint is an indicator of freshwater use that looks at direct water use and indirect water use, and can be regarded as a comprehensive indicator of freshwater resources appropriation, next to the traditional and restricted measure of water withdrawal. This study analyzed the spatial and temporal characteristics of water stress, and the water footprint of production in China. Water eco-function zoning in China was conducted according to three-order basins and combined with water ecosystem service assessment theory. The water eco-function zoning scheme in China revealed six first level eco-function zones: the Northeast Songliao Mountain and Plain Less Water Zone, North China Huang Sea and Huai Sea Plain Less Water Zone, Northeast Inland Dry Scarce Water Zone, South Mountain Hill Wet Zone, Qinghai-Tibet Plateau Water Tower Zone, Southwest Plateau Valley Wet Zone. There were 100 second level zones according to functional: water and water products supply function zone (life and production water, water products, shipping, hydropower, etc); water resources habitat sustain function zone (biodiversity sustain, aquatic habitat, spawning ground, wintering ground, etc); water resources environment regulation function zone (climate regulate, water self purification, reservation flood, etc); and water recreation service function zone (tourism, culture and education, etc). The study provides theoretical support for the scientific management of water resources and safeguards the security of national water resources. Our framework reveals water ecosystem health and trends in the development of watershed ecosystem protection and recovery strategies, and supports the transformation of national water resources management philosophy.