Vegetative barriers are increasingly used to reduce sediment export from cropland and thus mitigate negative off-site consequences of soil erosion. Here, we report and discuss the effectiveness of vegetative barriers implemented in Flanders (Belgium) to buffer the flows of water and sediment. The three types of vegetative barriers studied are made of straw bales, wood chips or bales of coconut- fibre. Based on three simulated runoff experiments performed in the field, we calculated the hydraulic roughness and sediment deposition ratio. Our experiments showed that the barriers made of coconut-fibre bales performed markedly better than those of straw bales or wood chips (Manning's n values of 1.355, 1.049 and 2.231 s m^-1/3 and a sediment deposition ratio of 19%, 38% and 64% for barriers made of straw bales, wood chips and coconut-fibre bales, respectively, during the first experiment). These values increased during subsequent experiments demonstrating the effect of sediment accumulating inside the structures. Especially for coconut-fibre bales, this accumulation increases the risk of runoff bypassing or overtopping the barriers. The barriers mainly retained sand and, to a lesser extent, silt and clay. As vegetative barriers have to be renewed every few years because of the decomposition of organic material, barriers made of locally available materials are more sustainable as a nature-based solution to erosion. We conclude that although the vegetative barriers made of coconut-fibre bales are superior in their regulation of flows of runoff and sediment, barriers made of locally sourced materials are more sustainable.

中文翻译：

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植物屏障在调节开放农业景观中模拟径流和沉积物通量方面的有效性报告（比利时佛兰德斯）

植物屏障越来越多地用于减少农田的沉积物输出，从而减轻土壤侵蚀的异地负面后果。在这里，我们报告并讨论了在佛兰德斯（比利时）实施的植物屏障缓冲水和沉积物流动的有效性。研究的三种植物屏障由稻草捆、木屑或椰子纤维捆制成。基于在现场进行的三个模拟径流实验，我们计算了水力粗糙度和沉积物沉积率。我们的实验表明，由椰子纤维包制成的屏障的性能明显优于稻草包或木片（曼宁的 n 值为 1.355、1.049 和 2.231 sm ^{- 1/3}在第一次实验中，由稻草包、木屑和椰子纤维包制成的屏障的沉积物沉积率分别为 19%、38% 和 64%）。这些值在随后的实验中增加，证明了沉积物在结构内积累的影响。特别是对于椰子纤维包，这种堆积会增加径流绕过或越过障碍物的风险。屏障主要保留沙子，并在较小程度上保留淤泥和粘土。由于有机材料的分解，植物屏障必须每隔几年更新一次，因此由当地可用材料制成的屏障作为基于自然的侵蚀解决方案更具可持续性。我们的结论是，虽然由椰子纤维包制成的植物屏障在调节径流和沉积物的流动方面具有优势，