| Bark beetles, widely distributed all over the world, are destructive pests in forest ecosystems. For instance, Dendroctonus armandi Tsai et Li, whose main host tree is Pinus armandi Franch , has been a important native forest pest in the Qinling Mountains. However, in the last decades, numerous beetle outbreaks have occurred in this forest region. Bark beetles attack living trees by boring through the bark and feeding upon the phloem tissue, so it is difficult to control them by chemical methods, since the later period of 1990's, the government has taken protection project for natural forest in the Qinling Mountains, therefore, it is increasingly essential to explore and utilize forest ecosystems to control bark beetles. This paper summarized and reviewed the history and current situation of bark beetles researches in six respects as follows: taxonomy, biology, pheromones, natural enemies, lethal mechanism and control strategies; The advance of ecological pest management researches was also summarized and reviewed in six respects including basic intension, cardinal principles, methodology, implement measures, fulfillment in practice and confronted main problems. In order to reveal the sustainable control strategy of bark beetles in the forest ecosystems in the Qinling Mountains, the types of plant communities infected with bark beetles, the structure and evolution characteristics of the main plant communities in different forest areas, the faunal composition and the distribution of bark beetles, the damage situation of Dendroctonus armandi and the distribution regularity of parasitic wasp in different habitats have been studied. The main results are as follows:1. The plant communities infected with bark beetles was divided into 27 forms which belong to 8 vegetational types.Based upon studies of forest vegetation in 6 areas, including Huashan, Fengyu, Niubeiliang, Jialingjiang, Yingzuishi and Huoditang, results showed that the plant communities which had been infected with bark beetles was divided into 27 forms which belong to 8 vegetational types.2. Study on the species diversity in different forest areas cleared the structurecharacteristic and change regularity of the main plant community in the Qinling Mountains.The species diversity of higher plant communities in different areas was measured. The result showed that from shrub communities to mixed coniferous and broadleaved forest communities, the Shannon-Wiener's diversity index, Pielou's evenness index and species richness presented an increasing trend; but from mixed coniferous and broadleaved forest communities to alpine coniferous forest communities and alpine meadow communities, the Shannon-Wiener's diversity index, Pielou's evenness index and species richness presented an decreasing trend. View the situation as a whole, the diversity of forest communities is higher than that of shrubs and meadow communities, the diversity of the deciduous broad-leaved forest is higher than that of coniferous forest. However, the Berger-Parker's dominance index presented a trend just on the contrary compared to Shannon-Wiener's diversity index, Pielou's evenness index and species richness. In the same forest communities, the Shannon-Wiener's diversity index, Pielou's evenness index and species richness on the south slope were higher than that on the north slope clearly.3. Study on the fauna of bark beetles cleared the faunal composition and characteristics44 species of 16 genera in three subfamilies were identified. Among them, 6 species were newly recorded to the Qinling Mountains. The faunal composition includes the Palaearctic, Oriental, Palaearctic-Oriental, Palaearctic-Oriental-Nearctic, Endemic and Nearctic ingredients. The faunal composition indicated that bark beetles species increased in the following sequence: Palaearctic-Oriental ingredients (23 spp.), Oriental ingredients (10 spp.), Palaearctic ingredients (5 spp.), Palaearctic-Oriental-Nearctic ingredients (3 spp.), Endemic ingredients (2 spp.), Nearctic ingredients (1 spp.).4. Cha...
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