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西北地区天牛区系的特点是 :区系形成年代较年轻 ;古北、东洋两大区系成分的交叉重叠 ;明显的水平分布和垂直分布 ;多数种分布相对集中 ;成灾性虫种多集中在人为活动频繁地区 ;成灾原因主要受人为因素的制约。造成目前西北地区天牛分布原因是在长期年代中由其内在分散力及外在制约因素共同作用的结果。
The fauna and flora of the Northwest Territories is characterized by the younger age of the fauna formation, the overlapping of components of the ancient North and East regions, the obvious horizontal distribution and vertical distribution, the relatively concentrated distribution of most species, Concentration in the frequent human activities; Disaster mainly due to human factors. The reason for the current distribution of Beautris in Northwest China is the result of the combined effect of its internal dispersal and external constraints in the long run.