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作 者:王志英[1,2,3] 岳书奎[1,2,3] 方虹[1,2,3] 王帆[1,2,3] 李开福[1,2,3] 宋金文[1,2,3]
机构地区:[1]东北林业大学 [2]黑龙江省鸡西矿务局林业处 [3]黑龙江省鸡西市林业局
出 处:《东北林业大学学报》1996年第4期41-45,共5页Journal of Northeast Forestry University
基 金:黑龙江省"八五"攻关课题。
摘 要:分别对落叶松绶尺蠖危害程度不同的林分进行了研究,其结果:在郁闭度为0.9、0.8的38和39年生的落叶松林内,平均每株针叶量分别为3.9755kg和4.3530kg;当落叶松失叶量在50%、75%、100%时,其材积损失分别为0.0022、0.0051、0.0074m3/株;损失率分别为28.57%、61.45%、85.88%;落叶松绶尺蠖幼虫的防治指标理论值为316.01头/株;按失叶量50%的防治标准时,其郁闭度0.8的林分防治指标为318.95头/株,郁闭度0.9的林分防治指标为291.29头/株。The larch stands damaged by Zethenia rufescentaria Motsch. in varying degree was studied. The total weight of needles per tree was 3.9755kg in 38-year-old larch stands with 0.9 crown density, and that in 39-year-old larch stands with 0.8 crown density was 4.3530kg. The measuring results showed that while a tree lost 30%, 75% and 100% of needles, the growth loss in volume was 0.0022m 3, 0.005m 3 and 0.0074m 3, respectively, or 28.57%, 61.45% and 85.88% loss rate. Theoretical value by density for control of Z.rufescentaria was 316.01 larvae per tree. Taking 50% of needles as a warning level, the density index for control of this pest in the larch stands with 0.8 and 0.9 crown densities was 318.95 larvae /tree and 291.29 larvae /tree, respectively.
分 类 号:S763.3[农业科学—森林保护学] S763.712.2[农业科学—林学]
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