针对以往研究中灌溉水利用效率内涵不完善、测算方法针对性不强、尺度转化关系不清晰，导致研究成果实用性差、不稳定等问题，运用系统工程思想，将灌区多水源联合运用视为一个复合系统，从复杂性的视角研究灌溉水利用效率的尺度效应及转化机理。构建科学合理的灌溉水有效利用程度识别指标体系，确定其复杂性特征，揭示灌区多水源复合系统灌溉水利用效率内涵和驱动机制；通过大田试验，提出适宜的测算定量公式和时空变异结构函数，确定其时空尺度结构性、方向性和自相关性，建立时空尺度效应下灌溉水利用效率点面转化函数关系，以及不同影响因素对其内在的响应机制，揭示灌溉水利用效率的时空尺度效应和定量转化关系；基于时空尺度效应，提出灌区灌溉水利用效率提高潜力策略和高效用水管理模式。研究成果对于丰富和完善灌溉水利用效率相关理论，解决黑龙江省灌区灌溉水利用率低下等诸多制约农业发展问题和实现黑龙江省粮食产能的新突破具有重大的理论和实践意义。

Aiming at unperfect connotation, simple calculating methods and obscure scale conversion relationship of Irrigation water use efficiency and leading to the findings having bad usefulness and instability, the joint use of irrigation area multi-water resources can be seen as a complex system by applying the system engineering idea and the scale effect and transformation mechanism of irrigation water use efficiency can be analyzed from complexity point. Firstly, the irrigation water use efficiency index system which is scientific and reasonably can be built and the complex feature can be analyzed. Then, the connotation and driving mechanism of irrigation water use efficiency can be revealed. Secondly, through field experiment, the appropriate calculating method and time-space structure variation function can be put forward. The spatial-temporal variation feature, point-surface function and each factors' response mechanism of irrigation water use efficiency can be dissected. The scale effect and transformation mechanism of irrigation water use efficiency can be revealed; Finally, Based on the scale effect, the laws of improving irrigation water use efficiency and efficient use water management model can be presented. The results have great theoretical and practical significance for perfecting irrigation water use efficiency relating theory, solving some problems that restrict agricultural development in Heilongjiang Province like low irrigation water use efficiency and realizing the new breakthrough of grain productivity in Heilongjiang province.