底坡及植被分布下的坡面水流能量损失特征试验研究

Research on Effects of Bottom Slope and Vegetation Distribution on Energy Loss Characteristics of Overland Flow

为了揭示坡面水力侵蚀过程中水流能量变化规律,进而为水土保持研究提供理论依据,利用变坡水槽在变化水深条件下的坡面流模拟试验,分析了5种坡比及3种植被分布(植被走向与水流夹角15°、30°、45°)下坡面水流能量损失特征。结果表明,在相同植被分布条件下,沿程能量损失随坡比增大而增大,随水深增大而减小后趋于稳定;相同坡比时,植被走向与水流夹角30°时沿程能量损失大于夹角45°的值,坡比0%、0.5%、1.0%时植被走向与水流夹角15°的沿程能量损失介于30°、45°之间,坡比1.5%、2.0%时其沿程能量损失最大;不同植被走向角的沿程能量损失随水深增大变化趋势相同。

Revealing the energy variation of soil erosion processes of overland flow can provide a theoretical basis for study of soil and water conservation. Experiment of overland flow with variable slope flume was carried out under conditions of varying water depth. And then energy loss characteristics of overland flow were analyzed under 5 slope gradients and 3 vegetation distributions, which the angle of between vegetation trend and water flow is 15°, 30 °and 45 °. The results show that under the same condition of vegetation distribution, energy loss increases with increase of slope gradient, and then decreases with increasing of water depth. Under the same slope gradient, energy loss in vegetation trend and flow along the angle of 30 ° is greater than that of the angle of 45 °. Under slope gradient of 0%, 0.5%, 1.0%, energy loss in vegetation trend and flow along the angle of 15°is between that of 30 °and 45 °. When the slope gradients are 1.5% and 2.0%, the value of energy loss is maximal. Under different direction angles of vegetation, the variation trend of energy loss with increasing of water depth is the same.