Study On Indicator And Spatio-temporal Distribution Of Rape Waterlogging In Hubei Province

Hubei Province is one of the major provinces in China that produce rape.Hubei Province boasts abundant water resources,moist weather in spring,and high precipitation,often causing continuous rain and water damage.The study of waterlogging has important significance for taking measures to prevent and reduce disaster and reducing economic losses in rape production.Based on the daily precipitation data from 69 meteorological stations from 1968 to 2017 in Hubei Province,this paper combines the historical rape yields in various regions in Hubei Province,defines the rape rain events,and determines the indices of the successive flooding index of rape in Hubei Province.The temporal and spatial distribution of rain,rain,and waterlogging in the growing period of rapeseeds was performed.A simple risk level division was carried out and the defense countermeasures were proposed for different risk level regions.The main conclusions of this paper are as follows:1.There is a negative correlation between precipitation and rapeseed yield during March and April.The three factors of daily average precipitation,continuous precipitation days,and sunshine hours are selected as the parameter characteristic quantities of the continuous rain index calculation model.According to the model finally found,the indicator of continuous rain and waterlogging of rapeseed was: continuous precipitation reached 4 days,daily average precipitation was greater than 0.1mm and sunshine hours was less than 0.3 hours.2.The grades of single-station rapeseed continuous rain and waterlogging were put forward,which were divided into three levels: mild,moderate and severe.According to the statistics of frequency of occurrence of waterlogging on selected typical sites,the results show that there are more frequent rainstorms in Jianghan Plain and East Hubei,and less frequent rainstorms in central and northern Hubei.3.According to the ranking index of rape waterlogging established in this paper,based on the meteorological data of Hubei Province for 50 years,statistical calculations were performed on the indexes,grades,and frequency of 69 stations.After that,the analysis of the distribution pattern of sub-stations,grades,and time periods was conducted.The analysis found that there were two major areas with high risk of continuous rain and waterlogging of rapeseeds in Hubei Province.The first is the southeastern Hubei Province,including Xianning City,Huangshi City,and Huanggang City;The second is the Jianghan Plain area,including Jingzhou City,Qianjiang City and Xiantao City.4.The occurrence of rape waterlogging in Hubei Province has shown an increasing trend.The area of disasters has been continuously expanding.Since the 1970 s,the disaster area has gradually spread from southeastern Hubei Province to southern Hubei Province.According to the temporal and spatial distribution of rape,a simple climatic zoning was carried out,and disaster prevention suggestions were made for each of the different production areas.