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关于林带走向与防风效果的关系,国内外有过大量的报道。传统的说法是:当林带与风向垂直时,防风效果最好,所以主林带应与当地主害风方向相垂直。南京林学院等单位,1960年在《苏北沿海农田防护林防护效果的研究报告》中指出:在林带背风面15倍树高处,当林带与风向垂直时,降低风速17.40%;当林带与风向成67.5度交角时,降低风速14.06%;当林带与风向成45度交角时,仅降低风速9.55%。观测林带宽10米;由5行国槐,4行苦楝,4行紫穗槐组成;透风系数为0.41。这项研究给了我们很大的启发,使我们考虑到,对于透风系
With regard to the relationship between forest belt and windbreak effect, there are a lot of reports at home and abroad. The traditional argument is: when the vertical with the wind direction, the best windbreak, so the main forest belt should be perpendicular to the direction of the main victims of the wind. Nanjing Forestry College and other institutes pointed out in 1960 that “in the research report on the protective effect of farmland shelterbelts on the northern Jiangsu coast,” it was pointed out that when the shelterbelts were 15 times as tall as the wind direction, the wind speed was reduced by 17.40% When the angle of 67.5 degrees is reached, the wind speed is reduced by 14.06%. When the forest belt intersects with the wind direction by 45 degrees, the wind speed is reduced by only 9.55%. Observed forest bandwidth of 10 meters; 5 lines of Sophora japonica, 4 lines Melia azedarach, 4 rows Amorpha; Ash permeability coefficient of 0.41. This study gave us great inspiration, let us consider, for the ventilation system