为了应对气候变化，提高作物抵抗灾害的能力，减轻灾害对作物生长的影响，利用位于黄土高原董志塬的西峰农业气象试验站观测资料，分析0~50 cm土壤水分变化对玉米产量的影响。结果表明，该区土壤贮水量呈逐年减少，气候趋向暖干化的变化特征。玉米全生育期内土壤贮水量变化具有阶段性：稳定期—迅速下降期—上升期；土壤水分突变年发生在2000年，之后递减趋势明显；玉米发育期日耗水强度最大时段出现在拔节—乳熟期，且土壤水分发生突变后比突变前日耗水量减少0.1 mm；玉米生长期水分利用效率呈现逐年增加趋势，但该趋势并不明显，土壤水分发生突变后（2000—2012年）比突变前（1990—1999年）水分利用效率增加了0.3 mm/kg。分析不同水分年型的水分利用效率发现，平水年水分利用效率最高，产量也最高，枯水年次之，丰水年水分利用效率和产量最低。

In order to deal with climate change, improve the ability to resist disasters crop, mitigate the impact of disasters on crop growth, the author analyzed the effect of soil moisture’s diversification from 0-50 cm to the maize yield with the observational data from Xifeng agricultural meteorological experiment station on Dongzhi highland at loess plateau. The results showed that: this region’s soil water storage was reducing while climate was becoming warmer and drier year by year. There’s a phased changing which from stable-phase to rapid-reduce-phase and to rise-phase in the whole growth period of maize. Soil moisture had a mutation in 2000, it reduced obviously since 2000. From jointing-stage to milky-stage in the growth period of maize, water consumption was the most, and the water consumption before mutation happened was 0.1 mm more than it after mutation happened. The efficiency of water using in the growth period of maize was increasing year by year, and it’s unobvious. The efficiency of water using after mutation happened (2000-2012) had a 0.3 mm/kg more increasing than it before mutation happened (1990-1999). Through the analysis about different climate-year-model’s water use efficiency, it was found that the water use efficiency and yield was the highest in normal year but the lowest in wet year.