快速城市化背景下,城市人工供水的比例迅速增加,由此产生的耗水不可忽视。传统水文模型在计算耗水时一般只考虑降水产生的蒸发,忽略人工耗用蒸发。为解析城市耗水过程,探究城市耗水机理,在观测城市耗水过程的基础上,划分城市耗水类型,建立城市耗水量计算模型。以北京市某区域为例,采用调查统计、实验监测和模型计算结合的方法,计算该区域2014年的耗水量为820.0 mm,明显高于传统水文模型的计算结果(多年平均值为494.0 mm)。分项结果显示:研究区绿地耗水贡献率为40.58%,建筑体耗水贡献率为38.70%(其中内部人工耗水为31.22%,屋顶截留雨水蒸发为7.48%),硬化地面贡献率为18.32%,水面贡献率为2.40%。结果表明:建筑体内部耗水量不可忽视,是人工用水消耗的主要组成部分,其耗水量与建筑体层数和居民数量成正比例关系。
Rapid urbanization have resulted in increasing water supply in urban areas and further led to more water dissipation from urban water uses.When calculating water dissipation,traditional hydrological models only considered evaporation from precipitation,usually ignoring the dissipation due to human water consumption.In order to analyze the urban water consumption process and better understand the urban water dissipation(UWD) mechanism,the UWD calculation model was developed based on the observation of the urban water consumption process and the categorization of UWD units.According to the results from statistical analysis,experiments and the mathematical model,the UWD of one region in Beijing in 2014 was estimated as 820.0 mm,which was significantly higher than that from the traditional hydrological model(494.0 mm averaged over many years).The results showed that the contributions of water dissipation from the green land,building,hardened ground and water surface were respectively 40.58%,38.70%(including 31.22% from human activities and 7.48% from building roofs),18.32% and 2.40%.It was concluded that water dissipation inside buildings was one main component of artificial water consumption and was non-negligible for the computation of the total UWD.The quantity of water dissipation of a building was proportional to the number of floors and residents in the building.