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毛白杨幼林地桑天牛主要死亡因子为:卵寄生蜂寄生、啄木鸟啄食和林木折断或枯死后影响其生长发育等。经过一代自然种群生命表初步研究,结果其种群趋势指效为3.84.
The main death factors of Populus simonii Populus tomentosa were: egg parasitic bee parasitic, woodpecker pecking and tree broken or dead after the impact of its growth and development. After a generation of natural population life table preliminary study, the results of its population trend refers to 3.84.