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早在五十年代,我省平原农区的风沙灾害严重地区,营造了一些零星片段的防风固沙林带。至六十年代初,发展为以全面改善农田小气侯,促进农业生产为目的,营造了一些分散的小片防护林网。进入七十年代,随着大规模的农田基本建设,进一步从改变旧的农田生态系统出发,一个县或一个地区统一规划,综合治理,营造了大规模的农田林网,出现了以林网为主体的点、带、网、片相结合的,比较完整的综合防护林体系。当前研究这些综合防护林体系的效益,对于深入认识平原农区林业发展的方向和推动这种防护体系的发展都具有十分重要的意义。
As early as the fifties, the sandstorms in the plains of our province were severely affected by wind and sand disasters, creating some windbreaks and sand belts with scattered fragments. By the early 1960s, some scattered small shelterbelts were created for the purpose of comprehensively improving the microclimate of farmland and promoting agricultural production. Enter the seventies, with the large-scale farmland capital construction, further from the change of the old farmland ecosystem, a county or a unified planning, comprehensive management, and create a large-scale farmland forest network, there Lin network The main point, belt, net, film combination, more complete integrated shelterbelt system. The current study of the benefits of these integrated shelterbelt systems is of great importance for understanding the direction of forestry development in the plain farms and for promoting the development of this system of protection.