Studies on water utilization for arid land farming

为发展干旱区农业用水，对旱地灌溉的研究报告和数据进行了系统的收集和评价。在此基础上，对干旱地区的水分利用特征进行了分析模拟。1.气象条件：利用彭曼法利用气象资料估算了干旱区主要点位的蒸散量。明确了各地区用水的差异。通过考虑地表反照率变化的土壤-地表热平衡分析，对干旱地区砾石覆盖的灌溉效果进行了评价。2.有限水分条件下的灌溉制度：在采用最优灌溉制度的情况下，蓄积在次土壤中的有效水分是可行的。通过水量平衡分析，探讨了干旱地区传统水箱灌溉系统的特点。3.灌溉方式与灌溉效率：提出了基于水力学试验的均匀灌水条件下滴管长度的确定方法。提出了滴灌用水方案中有效降雨评价的数值模型。4.输水系统水分流失的防治：通过对输水系统水量损失的模拟预测，考虑了不同条件下的水量损失评价和有效的防护措施。5.灌溉系统的水管理：在分析伊朗胡孜斯坦地区调查数据的基础上，提出了系统运行和水管理的方法。6.淋滤和排水：分别针对低地下水田和高地下水田的土壤和水分条件，阐明了实际积盐现象的特点。

For developing the water use in agriculture in arid regions, The research reports and data for arid land irrigation were colected and evaluated in systematic. The analytical simulations based on the data were made and discussed for the characteristics of the water use in arid conditions.1.Meteorological conditions: The evapotranspirations of the main points of arid lands were evaluated using meteorological data by Penman method. The differences of consumptive use of water among the various regiong were clarified. The effects of gravel mulch in arid regions were evaluated by the heat balance analysis on the soil-surface considering the albedo changing.2.Irrigation schedulings in limited water conditions: The effective water use storaged in sub soils was available, in case of the optimum irrigation scheduling was applied. The characteristics of the tank irrigation system traditionally used in arid regions were discussed by water balance analysis.3.Irrigation method and efficiency: The determination method of drip-hose length based on the hydraulic experiments was presented for uniform water application. The numerical model on the evaluation of effective rainfall was proposed for the water plan of drip irrigation.4.Prevention of water loss in conveyance system: The evaluation of water loss and the effective protection methods were considered under the various conditions by the simulation predicting the water loss in conveyance systems.5.Water management in irrigation system: The methods of the system operation and water management were proposed based on the analysis of surveyed data in Khuzistan, Iran.6.Leaching and drainage: The characteristics of the actual phenomena of salt accumulation were clarified for the soil and water conditions of the low ground water fields and the high ground water fields, respectively.