在华主席和党中央的亲切关怀下,一个平原绿化的群众运动正在蓬勃发展。一些营造较早的农田林网,已经发挥了明显的防护效益。 为了积累我省农田林网防护效益的资料,我们在今年五月份对铜山县耿集公社的农田林网进行了防护效益观测。在当地有关部门的支持和协助下,取得了一些资料,现初步整理如下。 （一）农田林网可以降低风速 由于防护林带的机械阻力和树木枝叶的摩擦和分散作用,通过农田林网的气流,不仅流场结构发生了变化,而且动能量也被削弱,从而降低了风速,改变了害风的性质。我们对林网内外距地面一米高处的 Under the cordial care of Chairman Hua and the party Central Committee, a plains greening mass movement is booming. Some create an earlier farmland forest network, has played a significant protective benefits. In order to accumulate data on the benefit of farmland shelterbelt protection in our province, we conducted a survey on the protection effectiveness of the farmland shelterbelt at the Gengji Commune of Tongshan County in May this year. With the support and assistance of the relevant local authorities, some information has been obtained and the preliminary arrangements are as follows. (A) farmland forest network can reduce the wind speed Due to the mechanical resistance of the shelterbelts and tree branches and leaves of the friction and dispersion, through the flow of farmland forest network, not only changes in the flow field structure, but also to weaken the kinetic energy, thus reducing the wind speed , Changed the nature of the typhoon. We are one meter above and below the surface of the forest network