【作者】 白美健；

【导师】 蔡林根；

【作者基本信息】 中国水利水电科学研究院 ， 农田水利工程， 2000， 硕士

【摘要】 大中型灌区是我国粮食生产的骨干基地，也是农业用水大户。由于工程老化和管理不善，这些灌区的灌溉效率低，节水潜力大。目前，大中型灌区的改造和灌区管理体制的改革，都旨在提高灌溉水的利用效率，从而达到节水灌溉的目的。本文以簸箕李灌区为背景对大型灌区灌溉性能现状进行系统评价，分析节水潜力，改进评价方法和技术，为灌区改造提出合理建议。。 全文分三部分对灌区灌溉性能进行评价：一，干渠部分，主要探讨配水渠道流量损失的计算方法。在考斯加可夫经验公式的基础上，结合干渠实际运行情况，提出平均流量法和积分法。以簸箕李灌区为例，将平均流量法和积分法应用于灌区干渠利用系数的求算；二，支、斗和农渠部分，主要以簸箕李灌区为例，介绍支、斗、农各级渠道利用系数的评价方法。主要思路是由点到面，将实验方法与理论公式相结合。首先选取典型渠道，采用多种实验方法观测渠道渗漏损失，根据实验观测结果，分析渠道具体渗漏过程，选择相应的理论公式；然后将各种实验方法与理论公式相结合，综合分析得出典型渠道的稳定入渗率和地下水顶托修正系数；最后，结合灌区实际情况，根据土壤质地，渠道断面尺寸对各级渠道进行概化分类，再结合考斯加可夫公式和水力计算公式，得出各级渠道利用系数与过流量的关系；三，田间部分，根据田间灌溉实验的实际观测值，利用灌溉模拟软件SRFR模型对灌溉过程进行模拟，采用反求法确定各土壤参数值。针对灌区实际情况，以影响田间水利用系数的各参数为依据，对灌区田块进行概化分类，模拟得出各类田块的田间水利用系数。然后进一步分析各类田块的入畦单宽流量与田间水利用系数的关系，最后为各类田块确定最适宜的入畦单宽流量和灌水时间。更多还原

【Abstract】 In China, the middle and large-scale irrigation system play an important role in food production. Due to ageing and poor management, these systems have low irrigation efficiency and a large potential for water savings. Therefore, an extensive rehabilitation and modernization of the irrigation systems has being carried out for increasing water use efficiency. This paper takes the Bojili irrigation district as an example to evaluate irrigation performance of the systems, to define the water losses and analyze underlying causes as a basis to rehabilitate and modernize the irrigation system. In order to adapt to conditions of the system, the evaluation methods have been selected and modified and new field test methods and procedures have been developed. In Boj iii Irrigation District, three levels .of irrigation water management can be distinguished: 1) the main system managed by the irrigation agency; 2) the farm system managed by a township irrigation station and a group of farmers; 3) the field system managed by the individual farmers. For the main system (main canals), the mean discharge model and the integral model have been developed based on Kostiakov equation. The model validation and the parameters calibration have been done with historical discharge records, and then water use efficiency of the main system has been estimated with both models. For the farm level (Lateral, tertiary and farm ditch), an evaluation procedure has been developed. Firstly, a typical canal was selected to measure the seepage losses with several experimental methods. Secondly, the seepage process was analyzed with the selected theoretical model to determine the saturated permeability of the canal bedding soil and the withstanding coefficient of the ground water table underlying the canal bed. Finally, the farm system was typified according to soils and section configurations of canals to generate the relations between the water use efficiency and the discharge at different types of canals. For the field system, according to the measured data in field irrigation experiment the irrigation process was simulated using the SRFR model, and the soil parameters were determined by inverse method .The field system was typified according to the soil types and basin size, and the water efficiency of all types was determined by simulating. Then the relation between the intake rate and the application efficiency was analyzed, the most suitable intake rate and application time for all types were defined.更多还原