中国灌溉水资源利用效率的空间差异分析

Assessing the Spatial Variation of Irrigation Water Use Efficiency in Grain Production of China

水资源高效利用是现代化灌区建设重要目标。从衡量灌溉水资源有效利用程度和真实粮食产出能力出发,计算了1998-2010年中国各省区的灌溉效率IE和水分生产率WP指标,并分析二者空间分布格局。结果显示:IE与WP的全国值分别约为0.452和1.108kg/m^3,区域间差异程度前者小于后者,且均有随时间增大趋势;二者均呈显著的空间聚集现象,指标值高的省区位于黄淮海平原及其周边省区,低值则分散于西北、西南、东南及东北地区在;IE与WP在描述灌溉水资源利用效率空间相对大小上相互不可替代,但可以融合得到同时涵盖二者功能的灌溉用水效率IWE指标。IWE可以衡量灌溉水资源综合利用效率并作为区域灌溉发展方向的依据。根据省区IWE与耕地灌溉率现状对不同地区灌溉、粮食生产及水资源管理政策进行了初步探讨。

Efficient utilization of water resources is an important goal for irrigation district construction. Irrigation efficiency （IE） and water productivity （WP） for irrigation water consumption proportion and the real ability of the grain output evaluation in irrigated system of 30 provinces during 1998--2010 were calculated, then we analyzed the spatial distribution pattern of irrigation water use efficiency of China. Results showed that national value of IE and WP were about 0. 452 and 1. 108 kg/m^3 respeetively; both of the indices increased over time. The regional difference of WP was bigger than that of IE. IE and WP value shown sigmhcant aggrega- tion, provinces with high values are centered with Huang-Huai-Hai plain, and ones with lower values distributed in Southwest and Northeast China. WP and IE can not be replaced each other in describing the space pattern of irrigation water use efficiency, but can be used to establish the index of irrigation water efficiency （IWE）. IWE can measure the comprehensive efficiency of irrigation water and used as the basis for regional irrigation development direction. According to provincial IWE and irrigated rate of cultivated land this paper discussed food production and water resource management policy of the country.