Evaluation of kinetic energy and erosivity potential of simulated rainfall using Laser Precipitation Monitor
Evaluation of kinetic energy and erosivity potential of simulated rainfall using Laser Precipitation Monitor
复制标题
DOI：
10.1016/j.catena.2015.09.017
复制
发表时间：
2016-02
期刊：
影响因子：
6.2
通讯作者：
D. Meshesha;A. Tsunekawa;M. Tsubo;Nigussie Haregeweyn;F. Tegegne
中科院分区：
文献类型：
--
作者：
D. Meshesha;A. Tsunekawa;M. Tsubo;Nigussie Haregeweyn;F. Tegegne
降雨动能是一个广泛认可的指标，用于衡量雨滴在雨淋侵蚀中分离土壤颗粒的能力。然而，估计给定降雨事件的动能 (KE) 具有挑战性，因为它涉及对雨滴的终端速度和液滴尺寸分布 (DSD) 的分析。一个优选的替代方案是将 KE 与降雨强度联系起来。因此，我们试图描述模拟降雨的特征，建立动能和强度之间的关系，作为时间（KEt，J m−2h−1）和体积（KEvol，J m−2mm−1）的函数，并检查每个事件的侵蚀潜力。使用降雨模拟器和激光降水监测仪（光学测速仪）来表征不同降雨强度（1.5 至 202 mm h−1）下的雨滴尺寸、终端速度和 KE。 KE 值的范围为 26.67 至 5955 J m−2h−1，KEvol 的范围为 16.10 至 34.85 J m−2mm−1，这与类似强度范围的自然降雨确定的值相当。 KEt 与降雨强度之间的幂律函数和多项式函数的决定系数 (R2) 分别为 0.99 和 0.98 (P< 0.0001)。 KEvo 和强度之间的最佳拟合关系是幂律函数（R2= 0.95；P< 0.001）。我们发现，在幂律函数中，侵蚀力与降雨深度有很强的相关性（R2=0.99；P<0.0001）。此外，无论降雨强度如何，KE 与雨滴大小的相关性比雨滴体积的相关性更强。
Rainfall kinetic energy is a widely recognized indicator of a raindrop's ability to detach soil particles in rainsplash erosion. However, it is challenging to estimate the kinetic energy (KE) of a given rain event, because it involves analysis of the terminal velocity and drop size distribution (DSD) of raindrops. A preferred alternative is to relate KE to rainfall intensity. Therefore we sought to characterize simulated rainfall, establish a relationship between kinetic energy and intensity as a function of both time (KEt, J m− 2h− 1) and volume (KEvol, J m− 2mm− 1), and examine the erosivity potential of each event. A rainfall simulator and Laser Precipitation Monitor (optical disdrometer) were used to characterize raindrop size, terminal velocity and KE at different rainfall intensities (1.5 to 202 mm h− 1). Values ofKEtranged from 26.67 to 5955 J m− 2h− 1andKEvolranged from 16.10 to 34.85 J m− 2mm− 1, which is comparable to values determined from natural rain of similar intensity ranges. A power-law function and a polynomial function betweenKEtand rainfall intensity had coefficients of determination (R2) of 0.99 and 0.98 (P< 0.0001), respectively. The best-fitting relationship betweenKEvoland intensity was a power-law function (R2= 0.95;P< 0.001). We found that erosivity had a very strong correlation with rainfall depth (R2= 0.99;P< 0.0001) in power-law function. Furthermore, regardless of rainfall intensity, KE is more strongly correlated with raindrop size than volume of raindrop.