黄河三角洲地区冬小麦微咸水灌溉制度模拟

Simulation of Brackish Water Irrigation Management for Winter Wheat in the Yellow River Delta

合理开发浅埋区地下微咸水用于灌溉不仅可以解决水资源短缺的问题,而且可以通过降低地下水位减轻土壤次生盐碱化,改善作物生长的水土环境。选择淡水资源紧缺、地下水埋深浅、土壤水盐运动剧烈的黄河三角洲地区,基于FEFLOW软件建立了引黄灌区的水流与溶质运移数值模拟模型,并应用率定和验证后的模型对多种微咸水（矿化度为2-5 g/L）灌溉方案进行模拟,综合考虑地下水位临界深度和冬小麦生育期耐盐极限,确立了较优的微咸水灌溉制度,包括一次性灌足关键微咸水、微咸水与淡水混合灌溉、微咸水与淡水轮流灌溉三种灌溉方式。

The rational development of shallow underground brackish water for agricultural irrigation, not only can solve the problem of watershortage, but also can descend underground water level to reduce the soil secondary salinization hazards, meanwhile , soil and waterenvironment for crop growth will be improved. This paper selected the Yellow River delta as the study area, where freshwater is in shortsupply, groundwater is shallow and the soil water and salt movement is active. In order to investigate the most applicable irrigation schedulewith slight saline water （ 2 - 5 g / L ） for winter wheat in the Yellow River delta, the validated finite element subsurface FLOW system（ FEFLOW ） model was used to evaluate the effect of various irrigation schedule on water and salt balance in soil,crop growth andgroundwater table. The simulated results indicate that the optimal irrigation schedule of winter wheat is a） key time of irrigation is neededwith enough slight saline water; b） two times of irrigation are needed with slight saline water mixed with fresh water and ; c） three or fourtimes of irrigation are needed with alternate of slight saline water and freshwater.