农作物需水量随气候变化的响应研究

利用甘肃省近80个气象站1961~2000年的常规气象观测资料以及夏秋主要粮食作物平均生育期资料,采用FAO推荐的Penm an-M on te ith公式结合作物系数,计算了各站夏秋主要粮食作物的需水量,分析作物需水量随时间和空间的变化特点以及对气候变化的响应.结果表明:农作物需水量与种植区的气候类型关系十分密切,从干旱-半干旱-半湿润-湿润地区其需水量呈现减小的趋势,越是干旱的地区作物需水量越大,越是湿润的地区作物需水量越小.作物需水量随气候变化的响应比较明显,在干旱、半干旱地区表现尤为突出.不同作物品种需水量相差较大,对气候的响应机制也有差异,一般来说夏粮的需水量小于秋粮,夏粮需水量对气候变化的响应比秋粮敏感.

Responses of Crop Water Requirements to Climatic Changes

With the data collected by nearly 80 meteorogical stations and the data of major summer and autumn grain crops during their growth of Gansu province in 1961~2000,the paper combines Penman-Monteith formulae to calculate the water requirements of major summer and autumn grain crops covered by various meteorological stations,and analyzes the temporal and spatial patterns and the responses of the water requirements to climatic changes.The results showed that the water requirements of crops closely relate to climatic types in their planting regions,apearing to decline in the order of dry,semi-arid,semi-humid,humid climates;The more arid the regions are,the higher the water requirement of the crops are,and the more humid the region are,the lower the water requirement of the crops are.The responses of the crops to climatic changes appear relatively obvious and particularly prominent in aird and semi-arid regions.Different crop varieties much differ in the their water requirements and differentiate in their responding mechanisms to climatic changes.Generally speaking,the summer grain crops consume less water than the autumn grain crops but the water requirements of the summer grain crops show a more sensitive response to climatic changes than the autumn grain crops.