Abstract:

Based on the data of Ground Conventional Meteorological Observatory in Jizhou and 43 regional stations in Tianjin from 1957 to 2018, we established the meteorological disaster indicators of walnut tree in main phenological periods, completed the spatialization of the index factors and analyzed their change with time, so as to provide information for the local planning of agricultural disaster prevention and control. We studied the spatial and temporal distribution characteristics of agro-meteorological disasters of walnut trees in Jizhou, Tianjin by five-day moving average method, climatic tendency rate method, entropy method and linear weighted synthesis method, and carried out the comprehensive regionalization. The results showed that: (1) mild chilling injury at germination stage and mild heat injury at fruit growth stage tended to increase, while moderate chilling injury, freezing injury at germination stage, mild chilling injury at leaf development stage, moderate chilling injury at flowering stage and continuous rain disaster at fruit growth stage tended to decrease; (2) the frequency of freezing disasters at germination stage, leaf spreading stage and flowering stage were higher, all of which reached more than 60%; the frequency of other disasters was less than 20%, the frequency of heavy precipitation disaster was the lowest at fruit growth stage; (3) the comprehensive scoring of disasters in northeast and east Jizhou was relatively low, indicating these areas could be most suitable for planting walnut trees.

Key words: walnut tree, agro-meteorological disaster regionalization, temperature, precipitation, chilling injury, freezing injury, heat injury