井渠结合灌区用水效率指标尺度效应研究框架

现有灌溉用水效率尺度效应的研究大部分集中在地表水灌区，而较少涉及地下水利用灌区，该文针对井渠结合灌区存在地下水回归利用的实际情况，以河北省石津灌区为背景，在国际水管理研究院（IWMI）提出的水收支方法的基础上引入回归水利用指标，提出了在井渠结合灌区进行用水效率指标尺度变化规律研究的工作框架。在所提出的框架中，评价指标选择IWMI体系，数据获取手段主要为资料收集和试验观测，尺度划分方式按照现有灌区管理模型分为灌区，干渠，分干，支渠和田间5个尺度。研究成果展现了灌溉用水效率尺度效应研究所涉及到的指标选取、尺度划分、水收支解析、水平衡要素数据获取方式、回归水分析5个方面的工作过程。该框架对于开展中国北方井渠结合灌区的节水灌溉尺度效应研究有着一定的参考价值和借鉴意义。

Scale effect research framework of irrigation water use efficiency indices in well-canal combined irrigation area

The current research of scale effect of irrigation water use efficiency was mainly focused at irrigation schemes with surface water resources, and less involved with groundwater irrigation. Based on the water accounting method developed by International Water Management Institute (IWMI), a general framework for analyzing variability of irrigation water use efficiency indices across scales in well-canal combined irrigation were proposed with return water utilization index, taking Shijin irrigation scheme in Hebei province as an example. In the framework, assessment indices developed by IWMI were explored to access irrigation water use efficiency, and five scales, namely irrigation scheme, main canal, branch main canal, branch canal and field scale, were selected according to the management mode of most irrigation areas in China. Data required for water accounting at those scales were mainly obtained from Shijing irrigation area scheme management agency as well as observation experimentation. Generally speaking, five key aspects of scale effect research of irrigation water use efficiency assessment indices, including assessment indices selection, scale division, water accounting, data collection and return water analyzing, were presented in the research, which could provide some references and experiences to the study on the scale effect of water saving in well-canal combined irrigation area in North China.