中国水资源短缺标准与分区评价

Water resources scarcity standards and zoning evaluation in China

明确水资源短缺标准和区域缺水状态是水资源规划管理工作的基础,但现状没有形成共识和标准,影响水资源刚性约束和“四水四定”等制度政策的有效实施。研究分析了水资源短缺的概念内涵,选取年降水量和人均可利用水资源量指标,考虑外调水量和可利用过境水量等影响要素,建立了“双指标、四要素、三等级”的水资源短缺评价体系,通过计算现代生产力水平下不同区域供养一个人平均水资源需求量,并与区域实际人均可利用水资源量进行对比,提出不同分区水资源短缺和严重短缺的判断阈值,其中黄淮海流域为人均可利用水资源量600 m^(3)和400 m^(3),松辽流域为人均可利用水资源量800 m^(3)和500 m^(3),长江流域、珠江流域、东南和西南诸河区为人均可利用水资源量1500 m^(3)和1000 m^(3)。研究提出的水资源短缺判别标准显著低于1989年Falkenmark提出的人均水资源量1700 m^(3)标准,主要原因在于生产力水平和灌溉用水效率大幅提升。据此开展全国345个地市水资源短缺评价,结果表明,不短缺、短缺和严重短缺的地市占比分别为55%、23%和22%。

Clarifying standards for water resources scarcity and regional water shortage status is fundamental to water resource planning and management.However,there is no consensus and standard on the current situation,which affects the effective implementation of water resources rigid constraints and policies such as“water dominates city and land development,population and production”.This study analyzed the concept and connotation of water resources scarcity,selecting indicators of annual precipitation and per capita available water resources,and considering factors such as external water transfer and available transboundary water.It establishes a“double indicators,four factors,three levels”evaluation system for water resources scarcity.By calculating the average water demand per person under modern productivity levels in different regions and comparing it with actual per capita available water resources,it proposes thresholds for water resources scarcity and severe scarcity in different regions:600 m^(3) and 400 m^(3) in the Huang-Huai-Hai River basin,800 m^(3) and 500 m^(3) in the Song-Liao River basin,and 1500 m^(3) and 1000 m^(3) in the Yangtze River basin,Pearl River basin,and southeast and southwest river regions.The scarcity criteria are significantly lower than Falkenmark’s standard of 1700 m^(3) per capitain 1989,mainly due to the significant improvement in productivity and irrigation water use efficiency.Based on this,an evaluation of water resources scarcity was conducted for 345 cities across the country,and the results showed that the proportions of cities with no shortage,shortage,and severe shortage are 55%,23%,and 22%,respectively.