Abstract:

In order to understand the influence of rainstorm disaster on blueberry ripening period, the meteorological data of blueberry ripening period at four stations in Dandong Region from 1991 to 2020 were used. Taking the rainstorm continuous for 3 days or more (daily precipitation ≥0.1 mm and at least 1 day precipitation ≥50 mm) as the disaster index, considering the frequency, intensity and duration of the rainstorm comprehensively, the disaster grades of light, moderate and severe rainstorm were worked out, and the change rule of blueberry rainstorm disaster was analyzed by the disaster frequency and station-to-station ratio. The results showed that during the 30-year period, the heavy rain disasters in Dandong showed a decreasing trend, and the frequency of heavy rain increased in the south and decreased in the north, especially in Fengcheng, the frequency tendency rate of rainstorm disaster was 0.19 times/10 a(p<0.01). The risk of heavy rain disaster was low in the early maturing period of 30 years, and the risk probability of light and moderate heavy rain disaster was close to or more than once in 20 years (≥5%), and no serious disaster occurred, the probability of occurrence of both mild and severe disasters was more than 10 years (≥10%). Kuandian Manchu Autonomous County is a high-risk area for heavy rain disasters. The disaster area is wide, the frequency is high and the intensity is heavy. The probability of occurrence of the three types of heavy rain disasters is more than once in ten years (≥10%).The results provide a scientific basis for dealing with the heavy rain disaster during the mature period of blueberry.

Key words: blueberry, mature period, rainstorm disaster, Poisson distribution, risk probability