城镇化是驱动区域用水变化的双刃剑,既可以通过刺激生产来促进用水总量增长,也可以通过优化用水结构和提高用水效率来抑制用水总量增长。以黑河流域张掖市为例,通过构建城镇化驱动用水变化的完全分解模型,定量测度了2000—2011年张掖市人口和经济城镇化过程对用水总量和用水效率变化的驱动效应。结果表明:张掖市人口和经济城镇化过程对用水总量均具有明显的减量效应,对用水效率均具有明显的增量效应,而且与人口和经济城镇化速度高度相关。因此建议干旱区绿洲城市在水资源约束下,应将城镇化作为优化人口结构、经济结构和用水结构,提高经济效率以及用水效率,并最终实现水一生态一经济良性循环的抓手。该结论对于科学认识干旱区绿洲城市城镇化与水资源利用的关系具有一定的参考价值。
Urbanization is a double-edged sword for water use change. It can stimulate economic development and increase total water use, and can also optimize water use. To measure the exact driving effects el was established, and was applied in Zhangy water use structure, enhance water use efficiency and decrease total of urbanization to water use change, a complete decomposition mod- e City, which is a typical oasis city in the Heihe River Basin. Re- sults show that, both the urbanization processes of population and economy have decresing effects to total water use, and increasing effects to water use efficiency. From 2000 to 2011, total water use was decreased 4.67 × 10^8 m3 by population urbanization effects and 12.64 × 10^8 m3 by economic urbanization effects. Per capita water use was de- creased 373 m3 per person by population urbanization effects. Ten thousand Yuan GDP water use was decreased 1 210 m3 ten thousand Yuan by economic urbanization effects. Moreover, the faster the urbanization processes of population and economy are, the greater the total water use will decrese and the water use efficiency will increase. Therefore, restricted by scarce water resources, oasis cities in arid areas of northwest China should accelerate the urbanization process, and take urbanization as an important task or approach to optimize the population structure, economic structure and water use structure, and enhance the economic efficiency and water use efficiency, so as to obtain a benign circle among the water - ecology - economy system. The results of this paper have significance to understand the relationship between urbanization and water resources utilization in arid areas of northwest China.