近日，美国哈佛大学Michael Hasson团队揭示了植被改变了河流弯曲的轨迹。该项研究成果发表在2025年8月21日出版的《科学》杂志上。

地球科学的一个基本公理是，植物的进化推动了全球河流动态的变化。值得注意的是，根据岩石中测得的沉积物加积方向方差所推导的河流表观弯曲度，在陆地植物演化后（约4.25亿年前）出现了显著增加。这导致了一种假设，即植被的上升引发了河流的蜿蜒。最近对贫瘠蜿蜒河流的研究挑战了这一观点，但古生代河流沉积物几何形状的变化仍未得到解释。

研究组认为，这是因为主题植被改变了河流弯曲在空间中的移动方式。利用卫星图像监测河流迁移，研究组发现河岸植被改变了点坝增生的方向，导致水流方向的推断方差增加62%。这些结果解释了为什么在前植被地层学中对曲流河流的认识不足。

附：英文原文

Title: Vegetation changes the trajectory of river bends

Author: Michael Hasson, Alvise Finotello, Alessandro Ielpi, Mathieu G. A. Laptre

Issue&Volume: 2025-08-21

Abstract: A primary axiom in geoscience is that the evolution of plants drove global changes in river dynamics. Notably, the apparent sinuosity of rivers, derived from the variance of sediment accretion direction measured in rocks, dramatically increased when land plants evolved, ca. 425 Ma. This led to the hypothesis that the rise of vegetation triggered river meandering. Recent studies of barren, meandering rivers challenge this notion, but the Paleozoic shift in the geometry of river deposits remains unexplained. Here, we suggest that it occurred because vegetation changes how river bends move through space. Using satellite images to monitor river migration, we find that bank vegetation alters the orientation of point bar accretion, resulting in a 62% increase in the inferred variance of flow direction. These results explain why meandering rivers have been under-recognized in pre-vegetation stratigraphy.

DOI: adv4939

Source: https://www.science.org/doi/10.1126/science.adv4939