中文摘要：

以栅格为基本单元,建立农田水分平衡模型,定量计算了西辽河流域玉米水分平衡量,揭示了西辽河流域玉米生长发育不同时段水分平衡特征与规律性,以期为区域农业可持续发展提供定量依据与支持。研究表明：（1）西辽河流域玉米全生育期的需水量为607mm,5月苗期最小,7、8月抽雄、灌浆期达到峰值;（2）西辽河流域玉米全生育期实际蒸散量约355mm,5月苗期最小,7月份达118mm,为全生育期的最高值;（3）西辽河流域玉米农田水分平衡量仅在5月的苗期出现少量的水分盈余,其它月份均表现为水分亏缺的特征,8月份亏水量最大;玉米亏水量地域差别较明显,呈现出由流域东部平原、西南部山地向中部科尔沁沙地逐渐递增的趋势。

英文摘要：

The river basin of Xiliaohe is the important maize planting area in China,and the maize acreage has continued to rise in recent years. This research took raster as basic unit to quantitatively analyze the water balance of maize,using the model of the water balance to reveal the situation of the water balance of maize in Xiliaohe river basin,and to provid theoretical basis for the sustainable development of agriculture in Xiliaohe river basin. The results showed that：（ 1） The demand of the whole growth period of maize is 607mm,which is the smallest in May,and the biggest in July and August.（ 2） The total of monthly actual evapotranspiration is 355mm. The actual evapotranspiration is at minimum in May,increases to 118mm in July,which is at the peak.（ 3） The water balance of Xiliaohe river basin appears a small amount of moisture surplus in May,other months show the characteristics of the water defecit,especially focus in August; The geographical difference of water defecit is obvious,we can find that the defecit of maize water show an increasing trend from the plain of the east and the mountain of southwest to the center of the Horqin Sandy Land.