半干旱区沙地高速公路防风固沙林营造技术及其效益研究

Technology of Wind-breaking and Sand-fixing Forest Establishment along Expressway in Semiarid Sandy Land and Benefit Evaluation

榆靖高速公路穿越毛乌素沙地腹地,风沙对公路的危害十分严重,主要表现为风沙对路面和路基边坡的风蚀和沙埋。提出了榆靖高速公路两侧防风固沙林综合防护体系,从公路路基向外依次为平整固沙绿化带,上、下风侧带宽都为20m;草方格沙障与植物固沙带,上风侧带宽为260～330m,下风侧带宽为100～150m;前沿阻沙带,设置1～1.2m高的高立式栅栏,走向与主风方向垂直;封沙育林育草保护带,上风侧带宽为300～500m,下风侧带宽为200～300m。4个防护带融为一体,起到了降低风速,固定流沙的作用,发挥出强大的防风固沙效益,极大地减少了风沙对公路的危害,保证公路畅通无阻,安全运营。

Yulin-Jingbian Expressway is situated in the southeast of Mu Us Sandy Land where wind and sand disasters（mainly including wind erosion on slope and sand burying on the road pavement）to the expressway are very serious.A comprehensive protection system of wind-breaking and sand-fixing forest along YulinJingbian expressway is proposed.The system is comprised of four belts：（1）sand-fixing green zone beside expressway,with bandwidth 20 m in both windward side and leeward side;（2）straw checkerboard barrier and plant sand-fixing zone,with bandwidth 260—330 m in windward side and 100—150 m in leeward side;（3）the forefront sand-stopping zone,with 1—1.2 m high upright fences perpendicular to predominant wind direction;（4）fenced nurturing grass and tree zone,with bandwidth 300—500 m in windward side and 200—300 m in leeward side.The integrated wind-breaking and sand-fixing forest system played an important role in reducing wind speed and fixing blowing sand.