Construction And Risk Assessment Of Grape Waterlogging And Drought Disaster Indicator In The Bohai Rim Region

This article takes the main grape producing areas in the Bohai Rim region of China as the research object,using the daily meteorological data,grape growing period data,and grape waterlogging and drought historical disaster data from 303 weather stations in the study area from 1980 to 2019,and fully considers the early water profit and loss status and the climatic suitable characteristics of the economic forest and fruit,construct the daily waterlogging index and the daily drought index,and construct and obtain the grape waterlogging and drought disaster grade indicator through the methods of disaster inversion and mathematical statistics,on this basis,the risk analysis of grape waterlogging and drought disasters is carried out,the result shows:(1)Based on the relative humidity index,comprehensively consider the impact of the water profit and loss status in the first 5 days and the first 50 days on the day,as well as climate adaptability,improve the relative humidity index,and construct the grape daily waterlogging index M₅ and daily drought index M₅₀.(2)In the Bohai Rim region,the initial indicators of waterlogging disasters at different growth periods and grades of grapes are mild waterlogging index M₅?3 for3 to 4 days,moderate waterlogging index M₅?3 for 5 to 6 days,and severe waterlogging index M₅?3 for continuous 7d and above.The cumulative value of each mild,moderate and severe waterlogging index in different growth periods is as follows:budding-new shoot growth period is 13-32,28-74,43 and above;flowering and fruit-setting period is 13-32,26-69,44 and above;fruit swelling period is 13-34,26-72,45and above;coloring maturity period is 14-36,29-86,47 and above.The verification results of grape waterlogging disaster indicators are consistent with the historical disaster records of grape waterlogging disasters.(3)The disaster grade indexes of light drought,moderate drought and severe drought in different growth periods of grapes in the Bohai Rim region are as follows:the indicators of light drought,moderate drought,and severe drought during the germination-new shoot growth period were drought index M₅₀?-0.4,lasting 14-39d,40-66d,67d and above;the indicators of light drought,moderate drought and severe drought during flowering and fruit setting were drought index M₅₀?-0.4,lasting 13-25days,26-79 days,80 days and above;the indicators of mild drought,moderate drought,and severe drought during fruit expansion period were drought index M₅₀?-0.4,lasting12-22 days,23-55 days,and 56 days and above;the indicators of light drought,moderate drought,and severe drought in the coloring mature period are drought index M₅₀?-0.4,lasting 13-28d,29-50d,51d and above.The verification results of the grape drought indicators are consistent with the historical disaster records of grape drought.(4)The occurrence range of waterlogging during each growth period of grapes in the Bohai Rim region was light waterlogging>moderate waterlogging>severe waterlogging.The range of waterlogging at different stages of grape growth is the budding-new shoot growth period<flowering and fruit setting period<fruit swelling period<coloring mature period.The high-risk areas of grape waterlogging disasters are mainly located in the southeast of Liaoning Province,the northeast of Hebei Province and the southeast of Shandong Province.The range of droughts at different growth periods and grades of grapes in the Bohai Rim region:budding-new shoot growth period>flowering and fruit-setting period>fruit expansion period>coloring mature period.The high-risk areas of grape drought are mainly the most areas of Hebei Province and the western regions of Liaoning and Shandong,while the low-risk areas are mainly located in the southeast of Liaoning and Shandong.