Changes in the Yellow River's course since the Last Glacial Maximum and its response to climate change and human activities

The Yellow River， characterized by its hydrological connectivity and sediment transport dynamics， has established a significant long-distance source-to-sink system on the continental shelf of the western Pacific. The sedimentary records derived from this system provide essential support for reconstructing the paleoenvironmental evolution of the region. However， current research faces challenges related to disparate data， and there remain numerous debates concerning the timing of river connectivity， the driving mechanisms of river system evolution， and the transformation nodes of human-environment coupling. This study employs a novel analytical framework centered on the source-to-sink coupling process， integrating diverse evidence from sediment source tracing， stratigraphic records， paleo geomorphological data， and historical literature. A stage-based evolutionary framework is utilized to systematically outline the changes in the Yellow River's course and the development of its river system since the Last Glacial Maximum， while also addressing existing controversies in the literature. The findings indicate that during the Last Glacial Maximum， the Yellow River was isolated due to ancient lake basins， resulting in a fragmented river segment state. In the context of climatic oscillations during the deglaciation period， the previously dispersed river systems gradually interconnected， leading to an eastward flow into the sea. In the early to mid-Holocene， a combination of climate warming and glacial meltwater contributed to the formation of a connected river system across the entire Yellow River basin. Following the emergence of anthropogenic levee construction in the lower reaches during the mid-Warring States period， the basin officially entered a phase of human-water interaction. Overall， the primary controlling mechanism of Yellow River evolution has transitioned from being predominantly influenced by climate and tectonics to a state where it is jointly governed by climatic factors and human activities. This research establishes a multi-evidence collaborative paradigm for analyzing river evolution， clarifying the phased evolutionary characteristics and driving mechanisms of the Yellow River since the Last Glacial Maximum， and addressing the limitations of previous fragmented studies. Furthermore， it provides theoretical references and case support for the study of similar large river source-to-sink sedimentary systems globally.