Impacts of different surface features on soil detachment in the subtropical region

International Soil and Water Conservation Research

Zhicheng Yang¹  Keli Zhang²  Zihao Cao³  Qianhong Ma³  Zaike Gu³  Mengyao Wei³ 

[1] Corresponding author. ,. Address: Xinjiekouwai Str. 19, Faculty of Geographical Science, Beijing Normal University, 100875 Beijing, China.;School of Teacher Education, Hebei Normal University, Shijiazhuang, Hebei 050024, China;State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China;

关键词: Vegetation;    Soil tillage;    Soil erosion;    Detachment rate;    Yellow soil;   

DOI  :  

来源: DOAJ

【 摘 要 】

Near-surface features have a great influence on runoff and detachment processes by overland flow, but the contributions are still unclear on steep slopes with yellow soil in subtropical humid regions. Field scouring experiments were conducted to investigate how near-surface features affect hydraulic parameters and detachment rate by overland flow. Five treatments and a baseline (disturbed rootless bare cropland) were designed to identify the contributions from stem-leaves, litter, biological soil crusts (BSCs), root systems and non-disturbance, respectively. The results showed that (1) the values of velocity, Reynolds number and Froude number for vegetated slopes were significantly lower than that of baseline, and stem-leaves made a greater contribution (average of 47.30%) to reducing kinetic energy than the other features; (2) the total contribution rate of grassland was 99.38%, and of this total, 1.19, 1.44, 2.49, 49.79 and 44.47% reductions were attributed to the stem-leaves, litter, BSCs, root systems and non-disturbance, respectively. Root system and non-disturbance dominated the detachment rate reduction; (3) with increasing flow rate or slope gradient, the total contribution rate remained between 98% and 100%; and (4) for each treatment, the relationship between detachment rate and hydraulic parameters remained constant, and the stream power was the best predictor to detachment rate. The study results are helpful in evaluating the effects of near-surface features on erosion control and providing reference for government decision-makers to choose appropriate soil conservation and management practices.

【 授权许可】

Unknown