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作 者:骆有庆[1] 黄竞芳[1] 杞杰[1] 刘志柏 刘曾三
机构地区:[1]北京林业大学林业资源学院 [2]山东省费县祊河林场,273400
出 处:《北京林业大学学报》1993年第3期75-87,共13页Journal of Beijing Forestry University
摘 要:1987年在山东费县祊河林场大滩分区栽植了3片感光肩星天牛的小美旱杨试验林,其立地条件一致,分别为天然接虫区、人工接虫区和对照区,整个试验区与外界虫源地之间由祊河自然隔离.1988年开始人工接虫,并逐年记录虫口密度和树木生长量.当光肩星天牛危害7年生以下的小美旱杨,且每株4年的累积刻槽数为9.4个,或排粪孔数为5.7个时:①与对照区相比较,人工接虫区小美旱杨的胸径、树高和材积生长分别下降14.06%、21.15%和37.49%;生物量下降37.75%;②光肩星天牛在侵害胸径约为7.0cm以下的小美旱杨幼林时,喜选择在径级较粗的树上刻槽和产卵.With identical site-type,3 plots of Populus simonii Carr.xP.nigra var.italics which is sensitive to Anoplophora glabripennis were planted in 1987,as a natural infestation plot,an artificial area was separated naturally from A.glabripennis source-trees outside by the Ban river.The first release of A.glabripennis adults in the artificial infestation plots was made in July 1988.The density of A,glaotjpennjs and the growth (DBH,H) of the poplars was recorded each year.When A,glabripennis damaged poplar trees under the age of 7 years,and the accumulated number of A.glabripennis impressions per tree was 9.4,or the accumulated number of A,glabripennis excretion holes per tree was 5.7 (sum of impression of excretion holes in 1988-1991).( 1 ) In comparison to the check plot,the diameter at breast height (DBH),the tree height and the volume in artificial infestation plot dropped 14.06%,21.15% and 37.49% respectively.Biomass dropped 37.75%.(2) In young poplar stands of less than 7.0cm DBH,A.glabripennis prefres infesting the larger tree to the smaller one.
分 类 号:S763.721.1[农业科学—森林保护学]
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