黄河流域城市绿地生态需水时空特征分析

界定了城市绿地生态需水和生态灌溉需水的内涵与特征,构建了城市绿地生态需水和生态灌溉需水的计算模型,对黄河流域45个地级以上城市的绿地生态需水与生态灌溉需水进行计算与分析.研究结果表明:①黄河流域城市绿地年生态需水量为44 749.7×104m3,年生态灌溉需水量为22 783.5×104m3.约占2000年黄河流域城市市区供水总量的4.85%.其中90.2%的生态灌溉需水集中在绿地植物的生长期(4～10月份);②植物需水和生态灌溉需水表现出不同的月变化趋势和空间分异规律.月生态灌溉需水的计算结果为黄河流域城市绿地生态用水的合理配置提供了科学依据.

Analysis on Temporal and Spatial Characteristics of Urban Greenspace Ecological Water Requirements in Yellow River Basin

As the key constituent of urban ecosystem health,urban greenspace has many kinds of function.Water is an important ecological factor of urban greenspace systemto keep it healthy.Ecological water requirements are the basis and of great importance in ecological water use allocation.In this paper,the meanings and characteristics of ecological water requirements and ecological irrigation water requirements for urban greenspace system are defined,and the methods are built up.45 cities in the Yellow River Basin are chosen as the research objects,and the ecological water requirements and ecological irrigation water requirements of the cities are calculated.The results indicate: first,yearly ecological water requirements of urban greenspace system in the Yellow River Basin are 44749.7 104 m3,yearly ecological irrigation water requirements are 22783.5 104 m3 with a percentage of 4.85% in proportion to the current urban supply(47.0 104 m3) in the Yellow River Basin,and the water demanded in growing period(4~10month) takes a percentage of 90.2% in corporation to the ecological irrigation water requirements.Second,there are different temporal and spatial characteristics of plant ecological water requirements and ecological irrigation water requirements,and the results of monthly ecological irrigation water requirements in the Yellow River Basin not only provide the scientific foundation of the ecological water use allocation for urban greenspace system,but also make it easy in practice.