荷兰瓦赫宁根大学H. J. Barneveld团队近日揭示极端的河流洪水暴露了潜在的侵蚀风险。该项研究成果发表在2025年7月10日出版的《自然》杂志上。

气候变化预计会增加河流洪水发生的频率和强度。洪水不仅会造成洪水的破坏和生命的损失，而且还会因堤岸坍塌和河床侵蚀过程而危及基础设施，而人们对这些过程知之甚少。常见的洪水安全计划包括堤防加固和河道拓宽。2021年，Metheme盆地的洪水造成43人死亡，基础设施损失数十亿美元。

通过对梅塞梅洪水的分析，研究组揭示了河流的不均匀加宽和河底沉积物的非均质性是如何抑制大规模侵蚀的。最近的一项防洪安全计划拓宽了河流，但却造成了瓶颈，要么是基础设施阻止了拓宽，要么是尚未实施。构造抬升在细粒沉积物之上形成了一层薄薄的顶部砾石层，加剧了河床侵蚀。

水流速度的大大提高产生了水下沙丘，这些沙丘的沟槽冲破了瓶颈处的砾石臂，暴露出容易被侵蚀的沙子，造成了极端的沙坑，其中一个超过15米深。该调查强调了在气候变化、洪水风险增加、河流拓宽空间竞争的情况下重新设计河流所面临的挑战，并呼吁更好地了解地下。

附：英文原文

Title: Extreme river flood exposes latent erosion risk

Author: Barneveld, H. J., Frings, R. M., Mosselman, E., Venditti, J. G., Kleinhans, M. G., Blom, A., Schielen, R. M. J., Toonen, W. H. J., Meijer, D., Paarlberg, A. J., van Denderen, R. P., de Jong, J. S., Beemster, J. G. W., Melsen, L. A., Hoitink, A. J. F.

Issue&Volume: 2025-07-10

Abstract: Climate change is expected to increase the frequency and magnitude of river floods1. Floods not only cause damage by inundation and loss of life2,3 but also jeopardize infrastructure because of bank failure and riverbed erosion processes that are poorly understood. Common flood safety programs include dike reinforcement and river widening4–9. The 2021 flood in the Meuse Basin caused 43 fatalities and a multibillion-dollar damage to infrastructure10. Based on analysis of the Meuse flood, we show how uneven widening of the river and heterogeneity of sediment deposits under the river can cause massive erosion. A recent flood safety program widened the river11, but created bottlenecks where widening was either prevented by infrastructure, or not yet implemented. Riverbed erosion was exacerbated by tectonic uplift that had produced a thin top gravel layer above fine-grained sediment. Greatly enhanced flow velocities produced underwater dunes with troughs that broke through the gravel armour in the bottlenecks, exposing easily erodible sands, resulting in extreme scour holes, one over 15 m deep. Our investigation highlights the challenges of re-engineering rivers in the face of climate change, increased flood risks, competition for river widening space, and calls for a better understanding of the subsurface.

DOI: 10.1038/s41586-025-09305-3

Source: https://www.nature.com/articles/s41586-025-09305-3