Studies on water utilization for arid land farming

为促进干旱区农业用水的发展，对干旱区农田灌溉的研究报告和资料进行了系统的整理和评价。在此基础上，对干旱条件下的水分利用特征进行了分析模拟。气象条件：利用气象资料，采用Penman法对干旱区主要观测点的蒸散量进行了估算。澄清了不同地区用水量的差异。通过考虑反照率变化的土壤表面热平衡分析，评价了干旱区砾石覆盖的效果。有限水分条件下的灌溉调度：在最佳灌溉调度条件下，地下土壤的有效蓄水量是可以利用的。通过水量平衡分析，讨论了干旱区传统储罐灌溉系统的特点。灌溉方法及效率：提出了基于水力试验的滴管长度的确定方法，以保证均匀施水。提出了滴灌方案有效雨量评价的数值模型。4 .预防输水系统失水：通过模拟预测输水系统的失水，考虑各种条件下的失水评价和有效的保护方法。灌溉系统中的水管理：通过对伊朗胡齐斯坦调查数据的分析，提出了系统运行和水管理的方法。淋滤和排水：明确了低地下水田和高地下水田土壤和水分条件下实际盐积累现象的特征。

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.