Drought Risk Assessment of Summer Maize at Different Growth Stages in Henan Province
[Objective]The study is to analyze the drought risks of summer maize in different growth stages,which has important reference value for guiding the formulation of drought prevention measures and reducing losses caused by drought.[Method]This study used daily meteorological data from 16 meteorological stations in Henan province from 1981 to 2019,and used the Crop Water Deficiency Index(CWDI)as the evaluation index.According to the Drought Grade of Summer Maize in Northern China(QX/T 260-2015),drought levels were divided for the 5 growth stages of summer maize.The frequency of drought occurrence,drought risk index,and their spatio-temporal distribution patterns at each level were analyzed.[Result]The total frequency of drought occurrence in different growth stages of summer maize is highest in the northern region of Henan,followed by the central and eastern regions of Henan.The total frequency of drought occurrence is highest during the tasseling to milking period,reaching over 96%,mainly consisting of moderate and extreme drought.The frequency of drought occurrence varies among different levels,but the frequency of drought occurrence in different growth stages and levels in southern region of Henan is relatively low.The drought risk index of summer maize in Henan province shows a spatial distribution pattern of gradually increasing from south to north during the sowing to emergence and emergence to jointing stages.The drought risk index of the entire Henan province is basically above 30 during the jointing to tasseling,tasseling to milking,and milking to maturity stages.[Conclusion]The risk of drought occurrence in summer maize is high in various regions during the jointing to tasseling,tasseling to milking,and milking to maturity stages.The risk of drought occurrence in various growth stages of summer maize is the highest in northern region of Henan and the lowest in southern region of Henan.Special attention should be paid to drought prevention and disaster reduction in the northern region of Henan.
summer maizegrowth stagedrought riskcrop water deficiency index
万方数据
维普
