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1997～ 1998年研究了山西省五台山和关帝山华北落叶松林受华北落叶松鞘蛾 (Coleophorasinensis )危害后 ,诱导树体自我补偿生长效应。结果表明 ,在 3种受害等级林分内 ,几项补偿生长相关指标如鲜叶重量、针叶长度、针叶内叶绿素含量变化与枝条生长的长度和粗度等 ,在中等受害区没有明显降低 ;相反 ,在某些时间区段还超过轻微受害的对照区。严重受害区的指标值明显低于对照区。因此认为 ,华北落叶松具有高度耐害性和自我恢复补偿生长效应。在中度受害区可以不采用防治措施 ,严重受害区防治目标是将虫口降低到中度受害的密度水平。缩小防治范围 ,降低防治目标和难度 ,减少化学防治
From 1997 to 1998, the effects of tree self-compensatory growth induced by Coleophora sinensis on Wutai Mountain and Guandi Mountain in Shanxi Province were studied. The results showed that there were no significant differences in compensatory growth-related indices such as fresh leaf weight, needle length, chlorophyll content in shoots and length and thickness of shoot growth among the three damaged grades ; Conversely, in some time periods it still surpassed the slightly affected control area. The index value of seriously injured area is obviously lower than the control area. Therefore, the Larix principis-rupprechtii is highly tolerant and self-compensating for compensatory growth. In moderately affected areas, prevention and control measures may not be adopted and the target of prevention and control of severe victimization areas is to reduce the population of insects to the density level of moderate victimization. Reduce the scope of prevention and control, reduce prevention and treatment goals and difficulties, and reduce chemical control