砾石覆盖对土壤吹蚀的抑制效应

Effect of Gravel Mulch Restraining Soil Deflation by Wind Tunnel Simulation

在风洞实验室模拟测定了不同砾石覆盖密度和覆盖方式的土壤吹蚀速率。结果表明，砾石覆盖对吹蚀速率的抑制作用可表达为砾石铺压的密度效应和空间排列效应。在一定的风力条件下，吹蚀速率随砾石覆盖密度的增加呈现指数递减变化；在一定的铺压密度下，不同铺压方式表现出不同的吹蚀抑制效应，从小到大依次是：平行条带铺压＜簇状铺压＜斜交条带铺压＜垂直条带铺压＜随机铺压。

The rates of soil deflation in different gravel spread density ( G d ) and gravel spread pattern were simulated and determined in the wind tunnel of Desert Research, Chinese Academy of Sciences. It was concluded that: ① soil deflation rates, at any certion wind velocity, decreased exponentially with the increase of G d ; ② the effects of gravel mulch restraining soil deflation under 5 experinced gravel spread patters, at a certain G d , follow a order of Parallel strip spread<Nest spread<Oblique strip spread<Vertical strip spread<Random spread. It was Random spread pattern that has the highest anti deflation effect, and when G d are 20%, 50%, 75% and 100% the effects are 34 36%, 69.41%, 82.94% and 92.91% of bare soil respectively. The results had revealed the positive ecology function of gravel gobi extensively distributed in desert area.