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采用踏查和标准地调查相结合的方法，对落叶松八齿小蠹发生规律进行了研究，结果表明：气候、立地条件、郁闭度、林木长势、林内卫生状况对该虫发生影响显著。在此研究的基础上，按立地条件等因子以及有虫株率将林分受害程度划分为４个危险等级，进行虫情监测。利用发育进度、有效积温的方法对该虫的发生期预测进行了研究，预测结果与实际发生基本一致。利用有效虫口基数和查迹法对该虫发生量进行了预测，其准确率均达到９０％以上。
Using the method of combining investigation with standard survey, the law of occurrence of Larix principis-rupprechtii was studied. The results showed that climate, site conditions, canopy density, tree growth and forest health had significant effects on the occurrence of the insects. On the basis of this study, according to the site conditions and other factors as well as the rate of insect strains will be divided into four levels of risk of forest damage, insect monitoring. Using the method of developmental progress and effective accumulated temperature, the prediction of the occurrence period of this pest was studied, and the predicted result was basically consistent with the actual occurrence. The effective insect population base number and trace method were used to predict the occurrence of the insects, the accuracy rate reached more than 90%.