内蒙古寒区水稻灌溉需求与降雨利用分析OA

Understanding the relationship between precipitation and rice irrigation requirements in the cold regions of Inner Mongolia provides crucial evidence for optimizing irrigation schedule and promoting efficient water resource utilization.Based on daily meteorological data from 1959 to 2017 at four representative rice stations in the cold regions of Inner Mongolia,this study constructed a water balance model.The Mann-Kendall test was applied to analyze the trends of water balance components,while the Pearson correlation coefficient and maximal information coefficient were used to reveal the relationships among these components.In addition,precipitation concentration degree and concentration period were employed to characterize the temporal distribution of rainfall.The results show that during the rice growing season in Inner Mongolia's cold regions,rainfall is relatively low(<500 mm)while crop water demand is high(>600 mm),resulting in significant overall irrigation demands:Kailu(921.1 mm)>Bairin Left Banner(799.7 mm)>Jalaid Banner(777.6 mm)>Zhalantun(669.5 mm).All sites exhibited high rainfall utilization rates(>80%)but low rainfall contribution rates(<40%).Although limited rainfall was efficiently utilized,it remained insufficient to meet irrigation requirements.In recent years,rainfall has shown a decreasing trend,while ETc has increased,leading to a growing dependence on irrigation.Under future climate change scenarios characterized by reduced rainfall and enhanced ETc,Inner Mongolia's cold regions can optimize irrigation patterns by integrating rainfall forecasts to enhance rainfall contribution and alleviate water resource pressure.