宁夏平原区分布式水循环模拟研究

根据平原区水循环的特点，建立了平原区分布式水循环模型，该模型以日为计算时段，根据行政区域、引排水渠道覆盖的灌域、土地利用类型以及作物种植结构划分水循环计算单元。模型以水平衡为基础，在任一计算单元沿垂直方向均可分为植被冠层、地表水、土壤浅层、土壤深层、潜水层和承压水层，按照水域、植被、裸地、农田、不透水域等不同土地利用类型计算蒸散发量，地表水模拟包括引水系统、排水系统、湖泊湿地和生活及工业用水系统。应用该模型详细模拟了宁夏平原区1991～2000年的水循环转化过程和供、用、耗、排水量关系，计算结果表明，若不加上黄河河道蒸发消耗水量，2000年平原区实际消耗黄河干流水量为33.53亿m3。

Distributed water cycle simulation for plain area in Ningxia Autonomous Region

A distributed water cycle model for simulating the water cycling in plain area of the Ningxia Autonomous Region, China, is established according to the hydrological and geographical characteristics of this area and human activities. In this model the calculation unit for water cycle is divided according to the regionalism, irrigation and drainage area, utilization of land and variety of crops and the calculation is carried out day by day. The model is based on the principle of water balance. In each unit the layers to be calculated along the vertical direction are vegetation layer, surface water layer, shallow soil layer, deep soil layer, phreatic groundwater and deep layer groundwater. The evaporations for different surfaces including water area, planting, soil utilization condition and waterproof surface are to be considered. The surface water system is composed of water diversion system, wetland of lakes, domestic and industrial use water. The proposed model is applied to analyze the water cycling process and the relationship between water supply and water consumption in this Region from 1991 to 2000. It is concluded that the actual water consumption in this plain area is about 3.353 billion m3 in the year of 2000.