Hillslope Erosion Mitigation: An Experimental Proof of a Nature-Based Solution

Soil erosion during rainfall events is affected by several factors, such as topography, soil type, land management, and vegetation cover. In this study, a series of tests investigates the influence of selected perennial herbaceous plants with a deep and strong rooting system, called MC1, on runoff generation and soil erosion. The tests on the investigated nature-based solution have been performed in the Cape Fear experimental hillslope with natural and artificial rainfall and for different vegetation heights. For all the experiments, runoff, soil moisture, and erosion data were observed and collected. The results obtained in this study suggest the following conclusions: (1) MC1 is effective in terms of soil erosion reduction already with a minimum vegetation height equal to 30 cm; (2) MC1 maximum efficiency, in terms of soil loss reduction, has been reached for a vegetation height equal to 70 cm; (3) In terms of the eroded material, the use of MC1 allows for a reduction of soil loss up to 300 times higher than the bare soil condition; (4) The use of MC1 allows for a reduction in the runoff coefficient up to 1/3 of the corresponding value in the bare soil condition.