鲁西北平原冬小麦耗水过程与节水灌溉管理模式讨论

本文利用禹城综合试验站土壤-植物-大气综合观测场冬小麦田间的小气候梯度仪和大型蒸渗仪的观测资料,结合作者建立的模拟SPAC系统中水、热、CO2通量和光合作用的综合模型,研究了冬小麦全生育期的耗水过程;根据模拟计算的土壤水分动态,对山东省鲁西北平原现行的灌水管理模式进行了讨论。(1)冬小麦全生育期耗水438mm;返青以前耗水占20%,拔节-灌浆期是耗水的旺盛时期,占67%;(2)灌水后地表以下1m处的渗漏量与土层前期储水量和灌水量有关,前期含水量越大,灌水量越大,损失越大,灌水利用率越低;(3)鲁西北平原现行的越冬水-返青水-灌浆水-黄熟水的灌水模式在各次的灌水量控制上应谨慎处理,否则会造成大量的水资源浪费,从而影响灌水利用率。

Water Use and Irrigation Management of Winter Wheat in the North-western Plain of Shandong Province

This paper presented results of water consumption at different growth stages of winter wheat by means of field experiment and model simulation. Meanwhile, the widely adopted irrigation water management strategies of winter wheat in the north western plain of Shandong province was discussed according to the model simulation results of soil water dynamics and crop water consumption process. Totally, water consumption of winter wheat during its growth season from 1998 to 1999 was 438mm in depth. Those consumed during the period from seedling to end of reviving, from shooting to grain filling, and from grain filling to harvest accounted for 20%, 67% and 13% of the total, respectively. Soil water dynamics simulation revealed that soil water drainage beneath 100cm was closely related to the soil water content before irrigation and water amount applied each time. The currently adopted irrigation practices should be checked on the basis of the field capacity and soil water status prior to irrigation. Otherwise, large amount of drainage will occur and lead to the low irrigation water use efficiency.