firebreak

The results showed that the minimal relative wind speed in the windward area of firebreak tree belt with a sparse and tight structure was down to 70% below, but in the windward area of the ventilate structure was only down to about 80%.

结果表明：紧密结构与疏透结构的防火林带迎风面的阻风性能比较好，最小相对风速达到70%以下，而通风结构的阻风性能最小，迎风面的最小相对风速在80%左右。

The proofing efficiency is closely correlated with the wind weather area of the firebreak tree belt.

防火林带的防火性能与阻风性能密切相关.

Wind Speed Distribution in the Aweather of the Firebreak Tree Belt in a Wind Tunnel Experiment A Test Study of the Ventilation Coefficient of the Firebreak Tree Belt on a Mountain Ridge

防火林带迎风面风速分布规律的风洞试验山脊防火林带透风系数的确定

So the effective structure of the firebreak belt in the ridge mountain was the sparse structure.

所以,山脊防火林带的有效结构为疏透结构.