植被盖度和灌木带状配置对近地表风速廓线的影响

采用便携式风速廓线仪分别对不同植被覆盖度和灌木带状配置的退化草原进行实验研究,结果表明:地表植被盖度越大,其降风速和防风蚀效果越明显,地表盖度分别为85%、35%、20%和小于5%时,距离地表2 cm处的风速相较6 4 cm处的风速降低幅度分别为7 2.4%、6 7.1%、6 1.7%和4 4.9%;灌木带越高,对牧草带有效保护距离越宽,植株高度大于0.7m的灌草带状配置有效保护距离均大于6m。因此,提高地表植被盖度和增大灌木带高度对近地表的风速廓线有较大影响,具有显著的抗风蚀效果。

Effects of Vegetation Coverage and Banded Repair on Near-surface Wind velocity Profile

Experimental researches have been done using portable wind speed profile meter on degraded grasslands with different vegetation coverage and shrub belt configuration , respectively .The results show that the greater the surface vege-tation coverage , the more obvious its effect on reducing wind speed and wind erosion prevention .Compared the wind speed at 2 cm and 64 cm high from the surface ,72 .4%, 67 .1%, 61 .7%and 44 .9%of the wind speed have been re-duced ,respectively , when the surface coverage ratio are 85%, 35%, 20%and less than 5%.Meanwhile , the higher the shrub belt , the wider the effective protection distance .For the shrub and herbaceous plant with banded configuration , when the plant height is higher than 0.7 m , its effective protection distance can reach not less than 6 m.Therefore, in-creasing the surface vegetation coverage ratio and height of shrub and herbaceous plant have a great influence on wind speed profile of near surface , have significant effect on reducing wind erosion .