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Plant roots can be very effective in stabilizing the soil against concentrated flow erosion. So far, most research on the erosion-reducing potential of plant roots was conducted on loamy soils. However susceptible to incisive erosion processes, at present, no research exists on the effectiveness of plant roots in reducing concentrated flow erosion rates in sandy soils. Therefore, the prime objective of this study was to assess the erosion-reducing potential of both fibrous and tap roots in sandy soils. Furthermore, we investigated potential effects of root diameter, soil texture and dry soil bulk density on the erosion-reducing potential of plant roots. Therefore, flume experiments conducted on sandy soils (this study) were compared with those on sandy loam and silt loam soils (using the same experimental set up). Results showed that plant roots were very efficient in reducing concentrated flow erosion rates in sandy soils compared to root-free bare soils. Furthermore, our results confirmed that fibrous roots were more effective compared to (thick) tap roots. Dry soil bulk density and soil texture also played a significant role. As they were both related to soil cohesion, the results of this study suggested that the effectiveness of plant roots in controlling concentrated flow erosion rates depended on the apparent soil cohesion. The nature of this soil type effect depended on the root-system type: fine root systems were most effective in non-cohesive soils while tap root systems were most effective in cohesive soils. For soils permeated with a given amount of fibrous roots, an increase of soil bulk density seemed to hamper the effectiveness of roots to

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Piping is a widespread phenomenon in the world and can significantly contribute to the downward movement of water, sediments, and nutrients. This study examines the hydrological functioning of soil pipes in a loess‐derived soil under pasture using hydrometric and hydrochemical analyses. It aims to investigate the relation between pipeflow, rainfall, and groundwater table fluctuations and to determine the dominant source of the water flowing through the soil pipes using both hydrometric and hydrochemical approaches. A rapid pipeflow response is observed when a threshold rainfall depth is exceeded. This threshold depth is larger in the summer (9 mm) compared with that in the winter (4 mm) which is related to the prestorm wetness of the soil. Hydrochemical analyses indicate that both groundwater and rainfall contribute to the pipeflow with a dominance of groundwater. This study shows that pipeflow can be an important hydrological pathway in loess‐derived soils with a clear seasonal pattern in pipeflow responses to rainfall events.