Based on daily minimum air temperature at the stages of flowering and young fruit of loquat from 7 observation stations in Lishui of Zhejiang during 1971-2017,the temporal and spatial characteristics of frozen injury at the stages of flowering and young fruit of loquat were analyzed by using the trend analysis method according to the frozen injury grade index,and the Mann-Kendall test was used to verify the trend,mutations and turning of frozen injury.The results show that the probability of frozen injury during flowering and young fruit stages of loquat occurring in Lishui was high with an annual mean of 5.3 d and 7.7 d,and the highest occurrence probability in late December for flowering stage and early January for young fruit stage,and they were focused on minor frozen injury.As for the spatial distribution of frozen injury,the probability increased from southeast to northeast,the lowest was in Qingtian county,and the highest was in Jinyun county.The long-term trend of frozen injury days during flowering and young fruit stages of loquat showed a significant decreasing trend,and the extreme minimum temperature rose significantly.The abrupt change of frozen injury occurred in 1989 and 1986 in Lishui,and the decreasing trend was the most significant in the early 21st century.%利用1971-2017年浙江丽水各县(市、区)枇杷开花、幼果期逐日最低气温观测资料,根据枇杷冻害等级划分指标,采用趋势分析法分析丽水枇杷开花、幼果期低温冻害的时空分布特征,并利用Mann-Kendall检验分析低温冻害的变化趋势和突变转折.结果表明:丽水枇杷开花、幼果期每年发生低温冻害日数分别为5.3d和7.7d;开花期12月下旬发生冻害日数最多,幼果期1月上旬发生冻害日数最多,且都以轻度冻害为主.枇杷开花、幼果期低温冻害日数由东南向东北递增,青田县发生低温冻害的几率最低(冻害日数分别为每年0.6d和2.7d),缙云县发生的几率最高(冻害日数每年分别为8.5d和13.6 d).枇杷开花、幼果期低温冻害的长期变化趋势表现为显著减少,且极端最低气温明显上升,即丽水枇杷开花、幼果期发生低温冻害的几率减小.枇杷开花、幼果期低温冻害减少发生突变点分别在1989年和1986年前后,且在21世纪初减少趋势最为显著.
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