宁夏黄河灌区森林蛀杆害虫危害的研究

通过在研究区布设标准地,统计蛀杆害虫的幼虫数、羽化孔数、刻槽数、受害株率以及危害高度、树高、树龄、树种,得出标准地5项指标:平均虫口、拥挤度、被害株率、感虫株率和抗虫株率,采用ISODATA动态聚类法,得出了蛀杆害虫危害状况分类及防治对策,为三北防护林工程蛀杆害虫的管理提供科学和理论依据,以促进宁夏黄河灌区生态和经济持续发展.

Investigation on Damage of Forest Trunk Borers in Ningxia Yellow- river Irrigating Region

Sample plots in villages and towns of Ningxia Yellow-river irrigating region. Number of larva, eclosion's hole and fluting, the rate of damaged trunks to the total, the damaged height , the height, age and species of trees were measured. 5 indexes on the sample plots including average density of pest population, crowded degree, the rate of damaged trunks, susceptible and against pests trees to the total were proposed. On the other hand, ISODATA developmental clustering to was used obtain the damaged status and prevention and cantrol countermeasures of trunk borers, to provide theoretical basis for controlling forest trunk borers and to promote the sustainable development of ecology and economy in Ningxia Yellow-river irrigating region.