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本文在连续 3年 (1 993～ 1 995年 )大量调查的基础上 ,研究了宁夏新建二代林网主要造林树种的主要害虫种群数量消长动态和发生规律。结果表明 :新建林网中具有潜在危险性的主要害虫为 :光肩星天牛 (Anoplophora glabripennis Motsch.)、木蠹蛾 (Cossuscossus orientalis Gaede &H olcocerus vicarius(Walker) )、枝梢害虫 (槐花球蚧 Eulecaniumkuwanai (Kanda) .&扁平球坚蚧 Parthenolecanium orientalis(Bouch) )。光肩星天牛种群呈下降趋势 ;木蠹蛾种群为上升趋势 ;槐花球蚧种群虽有下降趋势 ,但虫口密度依然较高 ;扁平球坚蚧在白蜡纯林中种群有逐年增长的趋势 ,而在混交林内数量变化平中有降。研究发现各害虫在合理的树种混交方式下 ,种群数量变化幅度小 ,危害轻 ,因而认为生产中只有营造合理树种搭配下的混交林才能防止和控制害虫的发生。
Based on a large number of surveys from 1993 to 1995, this paper studied the dynamics and occurrence of the main pest population dynamics in the main afforestation tree species in Ningxia. The results showed that the main pests with potential dangers in the new forest stand were Anoplophora glabripennis Motsch., Cossuscossus orientalis Gaede & H olcocerus vicarius (Walker), shoot-tip pests (Eulecanium kwanai (Kanda Parthenolecanium orientalis (Bouch)). The population of C. dorsalis showed a decreasing trend. The population of C. molitor was on the rise. Although the population of P. crassipes had a downward trend, the density of population was still high. The population of A. crassicarpa had a tendency of increasing year by year, The number of changes in the forest there is a drop. The study found that the pest species in the reasonable species mixed mode, the population changes in the magnitude of a small, less harmful, and therefore that only the production of reasonable species mixed with mixed forest in order to prevent and control the occurrence of pests.