南方果树春季冻灾罕例调查

2010年3月10日福建西北部果树生产遭受罕见的春季晚霜冻灾,闽东鹫峰山(N27°、E118°50′)、闽中戴云山(N25°40′、E118°10')、闽西博平岭(N24°50′、E117°10')以北区域均遭受不同程度的为害;受冻果树包括柑橘、梨、桃、李、(木奈)、柿、梅等主栽果类在内共计7科18属24种2变种,当年...

Investigation of rarely happened frost-damage to southern fruit in spring

On March 10,2010,fruit trees in northwestern Fujian were hit by a late spring frost with an unusual severity.The frost affected the regions north of Jiufeng Mountain(N27°,E118°50′) in eastern Fujian,Daiyun Mountain(N25°40′,E118°10′) in central Fujian,and Boping Ridge in western Fujian(N24°50′,E117°10′) to varying degrees.Fruit trees damaged by the frost included two variants in 24 species,18 genera,and seven families,such as orange,pear,peach,plum,apple and persimmon,and their yearly output dropped by about one-fourth.An analysis of the inclement weather condition shows that the frost bite of the fruit trees was the result of two climatic factors: First,in the early spring in February,the temperature was 2.5 ℃ higher than usual,which had a recurrence rate of 8.5 years(51/6);as a result,the phenological period of the fruit trees began about 15 days early.Second,the frost,which hit on March 10,was 10 days behind the local average ending date of frost,which normally falls on March 1,and the extreme minimum temperature had a recurrence rate of not less than 51/1 in early March;consequently,the flowering period or spring twig period of various fruit trees coincided with the late frost,resulting in extensive damage.No similar frost damage is found in the historical records on fruit trees in Fujian.An investigation in the wake of the damage shows that,in southern China,post-frost trimming in spring can be carried out after dead shoot tissues have become apparent.For vine grapes and kiwi fruits,to avoid bleeding,trimming should not be performed until after new buds are seen on the young shoots at the lower end of the vine a couple of days after the frost.As soil and water temperatures in spring have risen considerably,in the event of a radiation frost,fruit trees can be fumigated,sprinkled with water or covered up to prevent damage by frost.