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为揭示团聚体粒径动态变化对溅蚀的影响,通过室内人工模拟降雨试验,以第四纪粘土、泥质页岩发育红壤为研究对象,研究了酒精预湿润后的2～5mm团聚体在降雨过程中粒径动态变化及溅蚀率的变化。试验结果表明:在60mm/h雨强下,团聚体受雨滴机械打击破碎主要发生在降雨的最初阶段,团聚体>0.25mm百分含量(P>0.25)及平均重量直径(M)均随降雨时间(T)增加呈幂函数减小,溅蚀率(Dr)随降雨时间(T)增加呈幂函数增加,而溅蚀率(Dr)随团聚体平均重量直径(M)减小呈幂函数增大。为揭示不同土样在降雨溅蚀过程中溅蚀率的变化规律,利用团聚体稳定性特征参数—机械破碎指数(R)及降雨时间(T),建立了不同团聚体稳定性土样溅蚀率随降雨时间变化的经验方程,且方程可决系数较高(R2=0.82),揭示出团聚体稳定性越好,其破碎过程越缓慢,溅蚀率越小。研究结果为红壤区土壤侵蚀的防治及侵蚀机理研究提供了新思路。
In order to reveal the influence of dynamic change of agglomerate particle size on the splashing, indoor artificial simulated rainfall test was used to study the development of red soil in quaternary clay and shale shale. Dynamic Change of Particle Size and Change of Splashing Erosion Rate during Rainfall. The test results show that the aggregates are mainly affected by raindrops mechanical crushing and breaking at the initial rainfall of 60 mm / h under the condition of rainfall intensity> 0.25 mm (P> 0.25) and average weight diameter (M) The increase of time (T) showed a power function decrease, and the rate of splash erosion (Dr) increased with the increase of rainfall time (T), while the rate of splash erosion (Dr) decreased with the decrease of average weight diameter Increase. In order to reveal the regularity of splashing rate of different soil samples during the process of rainfall erosion, the stability of different agglomerates was established by using the characteristic parameters of aggregate stability - mechanical crushing index (R) and rainfall time (T) The empirical equation of the rate of change with rainfall time, and the higher coefficient of determination (R2 = 0.82), revealed that the better the stability of the aggregates, the slower the crushing process and the smaller the rate of sputter erosion. The results provide a new idea for the research on soil erosion control and erosion mechanism in red soil region.