基于数值模拟的太湖流域地区节水条件下水田灌排水量研究

太湖流域内农业用水粗放,水利用效率低下,农业面源污染严重,推广水稻节水灌溉势在必行。为了研究水稻节水灌溉对太湖流域用水总量控制的影响效应以及对太湖流域水资源量和水环境的影响效应,需要弄清在不同保证率下节水灌溉和淹水灌溉单位面积的灌溉水量和排水量。改进了逐日水量平衡法中蒸散发项和渗漏项的计算方法,并对该方法中各个参数的确定做了说明。最后以杭嘉湖区为例,选用1956-2000年系列资料模拟灌溉排水过程,同时采用P?Ⅲ型曲线计算不同保证率下节水灌溉和淹水灌溉的灌溉水量,并比较了两者的效益。

Research on the Irrigation and Drainage Water Quantity under the Condition of Water-saving Measures in the Area of Taihu Basin Based on Numerical Simulation

Agricultural irrigation water quantity in TaiHu Basin is so extensive that a high utilization efficiency of water is impossible,plus,the agriculture non-point pollution is very serious,therefore it is important to develop water-saving irrigation.In order to research the impact of water-saving irrigation on the total water requirement controls of the Taihu Basin and the water resources and water environment of the Taihu Basin,it is needed to make sure about irrigation and displacement water quantity per unit area of water-saving irrigation and inundative irrigation in the different probability of irrigation conditions.This paper improved calculation method of the evapotranspiration and leakage items of the daily water balance method,and illustrated how to estimate calculation parameters.Finally,taking Hangjiahu area as an example,the author selected a series of data from 1956 to 2000 to simulate the irrigation and drainage process,while used P-Ⅲ curve to calculate the irrigation and drainage water quantity of water-saving irrigation and inundative irrigation with the different probability of irrigation,and compared the benefits of both.