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机构地区:[1]西南林学院森保系 [2]四川省凉山州林业局
出 处:《西南林学院学报》1997年第3期34-39,共6页Journal of Southwest Forestry College
摘 要:榕片圆蚧在新银合欢树冠的分布为负二项分布;林间取样方式以折线式最佳,取样枝部位以树冠南上部最具代表性;抽样数量公式为N=27.6/x+18.3,序贯抽样公式按2.59,15.02,27.44头/cm2的防治指标分别为T0(N)=2.59N±5.5593N,T0(N)=15.02N±27.0897N,T0(N)=27.44N±48.5089N.In this paper,the crown canopy spatial destribution pattern and sampling technique of Aonidiella sotetsu Takahashi were studied. The results are shown as follows. The spatial distribution pattern of the pest in crown canopy is conformed with negative binomial distribution. The best method of collecting specimen is the broken-line one. The best place of collecting specimen is in the upper southern part of the crown canopy. The sampling number is calculated as the following model:N=27.6/+18.3. The models of sequential sampling are T0(N)=2.59N±5.5593N,T0([WTBX]N)=15.02N±27.0897N and T0(N)=27.44N±48.5089N which belong to 70%,80% and 90% crown canopy.
分 类 号:S763.35[农业科学—森林保护学]
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