论文部分内容阅读
在东北杨树冰核细菌溃疡病重发区和发生区，分别不同树种、林龄和立地条件，选设具有代表性的样地、采用野外均匀分布、典型整群抽样调查和树干解析的方法、获得１２０块样地，２７０株解析木的调查数据，确定了病情指数与材积损失率的相关数律，建立了东北地区杨树冰核细菌溃疡病材积损失估测的模型、并以此推算出了东北地区相应的经济危害允许水平模型和防治指标的计算模型。
In the northeast poplar inbreaks and occurrence areas of ice nucleation ulcer disease, respectively, different tree species, age and site conditions, the selection of representative plots, the use of uniform distribution in the field, the typical cluster sampling and trunk analysis methods, access 120 plots and 270 trees were analyzed to determine the correlation law between the disease index and the volume loss rate and established a model to estimate the volume loss of poplar inoculation in northeastern China. The corresponding economic hazard allows the calculation of the level model and the control index.