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机构地区:[1]西南林学院 [2]四川省凉山州林业局
出 处:《林业科学》1998年第2期51-57,共7页Scientia Silvae Sinicae
摘 要:本文组建了棕肾圆盾蚧Aonidielasotetsu(Takahashi)虫口密度与新银合欢Leucaenaglauca(L.)Benth枯枝率、枯枝率与木材损失率、林冠覆盖率分别与水土保持率间的一元回归模型、林冠覆盖率及年平均降雨量分别与水土保持量间的二元回归模型,确定了林冠覆盖率和水土保持量临界值以及木材年生长量、等于防治成本的水土损失以及木材损失和相应允许的林冠覆盖率损失,在此基础上,以改进的经济阈值模型:C=∑ni=1∑kj=1(PiRj)·D·F,求出70%、80%及90%林冠覆盖率下该虫的防治指标分别为:2.59、15.02、27.44头/cm2。In this paper,the simple linear regression relations between population density of Aonidiella sotetsu (Takahashi) and percentage of withered stick and between percentage of withered stick and damage percentage of trunk firewood, multiple regression relation among covering percentage of crown canopy and annual precipitation and water conservation, multiple regression relation among covering percentage of crown canopy and annual precipitation and soil conservation,simple linear regression relation between covering percentage of crown canopy and water conservation percentage,simple linear regression relation between covering percentage of crown canopy and conservation percentage,critical data of water and soil conservation ,critical percentage of crown canopy covering,damage percentage of water and soil conservation,damage percentage of crown canopy covering percentage and trunk firewood were studied.The results showed that the control threshold were 2.59,15.02 and 27.44 head scale/cm2,and at the same time the crown canopy coverings 70%,80% and 90% respectively.
分 类 号:S763.350.6[农业科学—森林保护学] S763.729.9[农业科学—林学]
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