江南水网地区防护林带主要有木麻黄林带、水杉林带、池杉林带和落羽杉林带。不同的林带,其防护效果往往相差很大,为发挥林带的最大防护效能,需确定一个最佳林带结构。在防护林研究工作中,常以林带的透风系数作为判断林带结构优劣的指标,并根据这个指标确定需要采取什么样的林业技术措施。近年来,我们对林带的透风系数和防护效能作了大 Jiangnan water network shelterbelts are Casuarina forest zone, Metasequoia forest belt, Taxodium shelterbelt and Taxodium cedar forest belt. Different forest belts, the protective effect is often very different, in order to play the maximum protective effectiveness of the forest belt, need to determine the best structure of a forest. In the research of shelterbelt, the ventilation coefficient of forest belt is often used as an indicator to judge the structure of forest belt, and according to this indicator, what kind of forestry technical measures need to be taken is determined. In recent years, we made a big contribution to the permeability coefficient and the protective effectiveness of the forest belt