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平原地区森林,是森林资源重要组成部分,北京市平原面积只占全市总土地面积的三分之一,林地面积就达173373.5公顷,林木覆盖率达23.57%。平原地区是人类生活和社会发展的主要聚集地,全市重点经济区县、重点企业和五分之四的人口在平原地区。北京市平原地区的森林资源,在防风固沙、保护农田、防止土地沙化以及遏止化工业发展和城市区域极度膨胀所致的环境恶化等方面,具有重大的战略意义。特别是农田林网,在保护农田以及农作物方面具有独特的作用。目前,由于地球环境的恶化,风沙灾害十分猖獗。土地在风力的作用下,大量的富有有机物质的活土层被从地表刮走,使土地逐渐沙漠化,变为不毛之地。我国土地沙漠化的危害也十分严重,有数
The plain area forest is an important part of forest resources. The plain area of Beijing Municipality accounts for only one third of the total land area of the city. The area of forest land reaches 173,373.5 hectares and the forest coverage rate reaches 23.57%. The plains area is the main gathering place of human life and social development. The key economic districts, key enterprises and four-fifths of the population of the city are in the plain areas. Forest resources in the plains of Beijing are of strategic importance in areas such as windbreak and sand fixation, farmland protection, prevention of desertification and the deteriorating environment caused by chemical industry development and the extreme expansion of urban areas. Especially farmland forest network, in the protection of farmland and crops have a unique role. At present, the sandstorm disaster is rampant due to the deterioration of the global environment. Land under the action of the wind, a large number of rich organic matter of the soil layer is scraped away from the surface, the land gradually desertified into barren land. The harm of desertification in our country is also very serious and numerous