北京观赏植物的冬、春季冻害分析

在2009年11月至2010年4月期间,北京地区出现了异常低温.与2000～2008年同期相比,平均气温降低了2.6℃,日均温＜0℃天数的频率增加了9.6％.这样的极端低温导致北京市植物园观赏植物的严重冻害.2010年春、夏季对17种160余株树木进行了调查.结果表明:广玉兰、紫薇、毛泡桐和天目琼花受冻害最为严重;其次是雪松、白皮松和紫叶李.冬季低温的强度与持续时间、树木的产地与抗寒性能以及栽植的生境等是导致树木受冻害程度差异的主要原因.

Freeze Injury Analysis of Beijing Ornamental Plants During Winter and Spring

During November 2009 and April 2010,the Beijing area suffered abnormal low temperatures.Comparing with situations during the corresponding periods from 2000 to 2008,the mean temperature decreased by 2.6℃ and the frequency of number of days with daily mean temperature below 0℃ increased by 9.6%.This kind of abnormal low temperatures caused severe freeze injury of ornamental plants in Beijing Botanical Garden.According to the investigation of 17 species and more than 160 individual trees during the spring and summer in 2010.The results showed that the most severe freeze injury appeared on Magnolia grandiflora,Lagerstroemia indica,Paulownia tomentosa and Viburnum sargenti,and then on Cedrus deodara,Pinus bungeana and Prunus cerasifera f.atropurpurea.The low temperature intensity and duration in winter,producing area and cold resistance of trees and planting habitat were primary causes resulting in different freeze injury degrees.