基于投入产出模型的黄河“几字弯”城市群用水特征与节水关键区域

黄河“几字弯”区域是黄河流域的关键节点,是实现中西部崛起的关键区域,也是黄河流域生态环境保护和高质量发展的战略支撑。然而,缺水已经成为制约“几字弯”地区经济社会发展的最大瓶颈。利用投入产出模型,从生产侧的实体水和消费测的虚拟水出发,分析“几字弯”地区18个城市的用水量、结构变化和流入流出特征,结合生产与消费两个方面提出了“几字弯”地区城市群节水的重点区域及产业供水调整的建议。（1）“几字弯”区域虚拟水用量由2007年648.5亿m3增加至2017年778.4 亿m3,增加了20.0%,但实体水用量仅变化了-0.04%,各城市虚拟水增长类型差异较大。（2）18个城市实体水占虚拟水的比例由2007年41.7%下降至2017年34.8%,水资源利用效率逐步提高;实体水的用水大户是农业,虚拟水的用水大户是制造业和农业,服务业实体水和虚拟水用量剧增。（3）区域18个城市虚拟水流入量增长明显,但整体仍呈现出虚拟水净流出的特征。制造业虚拟水流出量均在188.9亿m3以上,流入量均不足108.9亿m3,制造业在区域经济中具有一定的比较优势。（4）巴彦淖尔、中卫、吴忠、石嘴山和白银市是“几字弯”18个城市中重点节水的对象。在这些城市中,农业用水比重较大,产出较低,农业是今后节水的重点。鄂尔多斯、包头、石嘴山、乌海制造业具有比较优势,巴彦淖尔的农业用水系数远远高于18个城市的平均值,需要控制其农业用水。对于鄂尔多斯、包头、石嘴山、乌海、巴彦淖尔5市,需要向当地的优势产业制造业和服务业进行供水倾斜、提高比较优势。

Characteristics of water use in the "Jiziwan" urban agglomeration of the Yellow River Watershed and key areas of water-saving based on input and output model

"Jiziwan" section is a key node in the Yellow River Watershed, where is a key area for realizing the rise of the central and western regions, and it is also a strategic support for the ecological environment protection and high-quality development of the Yellow River Watershed. However, water shortage in this region has become the biggest bottleneck restricting the economic and social development. We used the input-output model to analyze the water consumption, structural changes, inflow and outflow characteristics of 18 cities in the "Jiziwan" area, including the physical water and the virtual water two sides. The key areas for water-saving in the urban agglomeration and suggestions for industrial water supply adjustment are presented. From the consumption side and the production side, we put forward the key points of water saving in this region and the suggestions for industrial water supply adjustment. (1) The virtual water consumption in the "Jiziwan" area increased from 64.9 billion m3 in 2007 to 77.8 billion m3 in 2017 with increase of 20.0%, but the entity water consumption only changed -0.04%, and the growth types of virtual water in different cities are quite different. (2) The ratio of entity/virtual water in 18 cities dropped from 41.7% in 2007 to 34.8% in 2017, and water resource utilization efficiency has gradually improved; the industry with the highest water consumption is agriculture, and the higher virtual water industry are manufacturing and agriculture. The consumption of entity water and virtual water in the service industry has increased sharply in this period. (3) The inflow of virtual water in 18 cities has increased significantly, but the virtual water outflowing is still mainly in this area. The outflow of virtual water from the manufacturing industry in 18 cities is above 18.9 billion m3, and the inflow is less than 10.9 billion m3. That shows the manufacturing industry has higher comparative advantages in "Jiziwan" area. (4) Bayannur, Zhongwei, Wuzhong, Shizuishan and Baiyin in "Jiziwan" region are the key cities for water-saving. In these cities, the agriculture water consumption is larger and the output is lower than other industries, and the agriculture is the focus of water-saving firstly. The manufacturing industries of Ordos, Baotou, Shizuishan and Wuhai has the comparative advantages to others. The agricultural water use coefficient of Bayannur is much higher than the average value of 18 cities, and agricultural water use needs to be strictly controlled. It is necessary for Ordos, Baotou, Shizuishan, Wuhai and Bayannur to tilt the water supply to the local advantageous industries, manufacturing and service industries, and improve their comparative advantages.