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我国是世界上森林病虫害发生比较严重的国家之一,尤为引人关注的是,随着全国造林绿化事业的不断发展,我国绝大部分人工林和部分天然次生林已经步入森林病虫害的高发期,呈发生面积起伏波动和危害明显加重的趋势.“三北”地区的杨树蛀干害虫、南方集体林区的松毛虫和以沿海?
China is one of the countries where forest pests and diseases occur more serious in the world. What attracts more attention is that with the continuous development of afforestation undertaking in our country, most of the plantations and some natural secondary forests in China have entered the high incidence of forest pests and diseases, An ups and downs of the area showed a significant increase in the risk of fluctuations and hazards. Poplar weeds in the “Three North” regions, pine caterpillars in the southern collective forest and coastal areas?