River terraces along the Liujiang River in Southwest China and their implications for understanding fluvial processes on the Guizhou Plateau since the Late Pleistocene

Abstract River terraces serve as excellent indicators of the landform evolution of the Guizhou Plateau. This paper presents the results of terrace investigation and optically stimulated luminescence (OSL) dating focused on five sections along the Liujiang River of the southeastern Guizhou Plateau. The OSL ages of the terraces range from 0.21 ± 0.02 to 16.0 ± 1.4 ka for the first terraces (T1) and from 3.5 ± 0.3 to 26.5 ± 3.3 ka for the second terraces (T2), which are much younger than those of other basins on the Guizhou Plateau. These ages, considered in tandem with the results of previous investigations, enhance our understanding of the fluvial landform evolution of the Guizhou Plateau since the Late Pleistocene. On the Guizhou Plateau platform, terraces are considered to be the response of river evolution to tectonic uplift, indicating a relatively slow geomorphic process. In the slope zone, climate change has had a significant impact on the fluvial landform processes, driving the formation of the younger terraces along the Liujiang River. In the platform–slope transition zone, the evolution of terraces was driven by both tectonic uplift and climate change, where the landform processes were dominated by strong headward erosion.