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河北省塞罕坝的生态建设历程大体可分为两个阶段,自1962年建场至1982年属造林为主阶段,自1983年至今属经营为主、造林为辅阶段。多年来,塞罕坝累积营造人工林保存面积达86万亩,累积经营抚育森林和封山育林面积达210余万亩,累计治理和消灭荒沙面积90余万亩。科学的人工造林和集约经营使林场的森林资源发生了质变和量变,生态体系建设成绩斐然。一、有害生物防治现状林业病虫鼠害是无烟的森林火灾。近年来,随着全球气侯变暖,适生的害虫种类不断增加,以前未发生过的落叶松毛虫、落
The course of ecological construction of Saihanba in Hebei Province can be roughly divided into two stages, from the establishment of the site in 1962 to the afforestation-based stage in 1982. Since 1983, it has been dominated mainly by afforestation. Over the years, Saihanba has accumulated a total of 86 million mu of preserved plantations and accumulated more than 210 million mu of forests for afforestation and afforestation. It has accumulated more than 90 million mu of land for waste management and elimination. Scientific afforestation and intensive management have made qualitative and quantitative changes in the forest resources of forest farms, with remarkable achievements in ecological system construction. First, the status of pest control Forestry pests and diseases are smoke-free forest fires. In recent years, with the warming of the global climate, the species of suitable pests grow continuously, and the larch caterpillars