摘要
松墨天牛在千岛湖区分布普遍，危害严重，有虫株率达８．４％，致死株率达６．０％，平均虫口密度为９９．１～１５５．８头株－１，最高单株虫口达５４４头。该天牛在松树中多分布于树冠层，自上而下，虫口数呈递减趋势；不同方位分布比例为南北＝６０．８３９．２；木材内虫口数占侵入孔数的８１．９％，说明自然死亡率达１８．１％。
Monochamus alternatus is widely distributed over Qiandao Lake area,causing serious injury to pine trees.The rate of pest insect infection is 8 4%,with a death rate of 6 0%.The average density is 99 1～155 8 pests per plant,and the highest density reaches 544 pests per plant.The pests are mostly distributed in the crowns of the pines,with gradual deduction of pest number from above to below.The south/north ratio of distribution is 60 8∶39 2.The number of pests inside timber takes up 81 9% of the number of the invaded holes,which indicates a natural death rate of 18 1%.
出处
《浙江林学院学报》
CSCD
1998年第2期176-180,共5页
Journal of Zhejiang Forestry College
关键词
千岛湖
松墨天牛
分布
危害
马尾松
Qiandao Lake
Monochamus alternatus
distribution
disasters
Pinus massoniana
