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中国进行不同类型的防护林系统建设始于50年代初期。经过40年的努力,其巨大的成功和这些林木特有的多用性,已引起了世界范围的关注。目前防护林网面积为3000万hm~2,可用林未体积为85000万m~3。防护林占全国造林总面积和森林恢复总面租的大约10%～13%,而且还提供了大量的林产品和非林产品。最近几年,防护林面积的年增量已经达到100万hm~2。中国森林覆盖率的逐年增加,并产生了显著的生态、经济和社会效益一定程度上就与此有关。发展防护林系统的主要限制因子是由于资金短缺、缺乏教育而造成的管理不力。对这些林木进行更好的管理,特进一步提高它们的经济、社会和环境效益。
The construction of different types of shelterbelts in China started in the early 1950s. After 40 years of hard work, its enormous success and the unique versatility of these trees have drawn worldwide attention. At present, the area of shelterbelts is 30 million hm ~ 2, and the available forest volume is 850 million m ~ 3. Shelterbelt accounts for about 10% to 13% of the total afforestation area and total forest rent recovered in the country, but also provides a large amount of forest products and non-forest products. In recent years, the annual increase of shelterbelts has reached 1 million hm ~ 2. To some extent, China’s forest cover has been increasing year by year and has produced remarkable ecological, economic and social benefits. The main limiting factor in the development of shelterbelt systems is poor management due to lack of funds and lack of education. Better management of these trees further enhances their economic, social and environmental benefits.