State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi 712100, China.
State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A&F University, Yangling, Shaanxi 712100, China.
Sci Total Environ. 2018 Feb 15;615:240-252. doi: 10.1016/j.scitotenv.2017.09.238. Epub 2017 Sep 29.
Soil erosion is complex in the wind-water erosion crisscross region of the Chinese Loess Plateau, as interleaving of wind and water erosion occurs on both temporal and spatial scales. It is difficult to distinguish wind erosion from the total erosion in previous studies due to the untraceable of aeolian particles and the limitation of feasible methods and techniques. This study used beryllium-7 measurements to study wind erosion in the wind-water erosion crisscross region on the Chinese Loess Plateau arms to delineate wind erosion distribution, to analyze its implication to erosive winds and surface microrelief, and to determine correlations between erosion rates and slope gradients. Results obtained using beryllium-7 measurements based on observation plots were verified with saltating particle collection method, and were also verified on a field scale. Results indicated that the effective resultant erosion wind was from northward, which was proved by the eight-directional distributed saltating particles. The microrelief of the ground surface contributed to the formation of high or low erosion centers. Wind erosion rates increased with a linear (R≥0.95) or exponential (R≥0.83) fitting increase in the slope gradients as reported in previous studies. Compared to wind erosion on field scale, both the plots and fields exhibited similar distribution patterns in wind erosion isolines. We also determined that the wind erosion rate for two fields estimated, based on equations developed from plot scale was acceptable. This study validates the feasibility of beryllium-7 measurements for soil-wind erosion field experiments and the potential to expand this approach to real field conditions.
土壤侵蚀在黄土高原的水蚀风蚀交错区是复杂的,因为风蚀和水蚀在时间和空间上都相互交织。由于难以追踪风成颗粒以及可行方法和技术的限制,以前的研究很难将风蚀与总侵蚀区分开来。本研究使用铍-7 测量来研究黄土高原臂上的水蚀风蚀交错区的风蚀分布,分析其对侵蚀性风和风蚀区表面微地形的影响,并确定侵蚀率与坡度梯度之间的相关性。基于观测样地的铍-7 测量结果通过跳跃颗粒收集法进行了验证,同时也在野外尺度上进行了验证。结果表明,有效侵蚀风来自北方,这一点得到了来自八个方向的跳跃颗粒的证明。地表微地形有助于形成高或低侵蚀中心。风蚀率随坡度梯度呈线性(R≥0.95)或指数(R≥0.83)拟合增加,这与以前的研究结果一致。与野外风蚀相比,样地和野外都表现出相似的风蚀等压线分布模式。我们还确定了基于样地尺度方程估算的两个样地的风蚀率是可以接受的。本研究验证了铍-7 测量在土壤风蚀野外实验中的可行性,并为将这种方法扩展到实际野外条件提供了潜力。