沙柳灌丛植株形态与气流结构野外观测研究

通过野外观测,研究了毛乌素沙地南缘平沙地人工栽种单行沙柳灌丛的植株形态与气流结构.结果表明,沙柳灌能降低迎风侧和背风侧的近地面风速,使沙粒在植株下部沉积.积沙体积(V₂)与植株体积(V₁)相关性较高(R=0.696).单行沙柳灌丛在4 m高处风速为6 m·s^-1时的气流结构特征为:迎风侧3H处风速已降低,2 H处风速又得到加强,之后在背风侧迅速降低,1 H处达到最低值,然后逐渐恢复到旷野风速.防护距离约为17H',有效防护距离约为13 H'.沙柳灌丛对植株高度以上高度处风速影响较小.

Field investigation on Salix psammophila plant morphology and airflow structure

A field investigation in the flat sands of southern Maowusu sandy land showed that artificially cultivated single line Salix psammophila could accumulate sand because the plant decreased the windward and leeward wind velocity. There was a significant correlation (R = 0. 696) between accumulated sand volume (V2) and plant volume (V1). When the wind velocity at 4 m height of single-line S. psammophila was 6 m x s(-1), the wind velocity decreased at 3H windward, increased at 2H windward, and then steeply decreased leeward, reached the lowest value at 1H leeward and gradually recovered to the open field velocity. The protection distance of single-line S. psammophila was about 17 H', and the effective protection distance was about 13 H'. Single-line S. psamnmophila had little effect on the wind velocity above plant height.