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在多风地区的旱作农业生产中,保护土壤、防止风蚀是粮食增产的关键。营造农田防护林是旱作农业生态系统中最有价值的生物工程。发生风蚀的主要动力因子是风,防护林正是削弱或消失风的破坏性,从而起到保护土壤的作用。目前,对各种类型防护林带的防护效应问题,国内外都已有深入的研究。但就许多特殊地区而言,因土地限制,林带不能配置太密,或因气候和土壤条件的限制,树木生
In dry farming in windy areas, protecting the soil and preventing wind erosion is the key to increasing grain output. Building farmland shelterbelts is the most valuable bioengineering project in dry farming ecosystems. Wind erosion is the main driving force of wind, shelterbelt is to weaken or disappear the destructive wind, which play a protective role of the soil. At present, the protection effect of various types of shelterbelt has been studied both at home and abroad. However, for many special areas, because of land restrictions, forest belts can not be configured too densely, or due to climatic and soil conditions,