Reconstructing Holocene coastal environmental evolution is essential for understanding the dynamics of modern coastal systems and anticipating their future responses to environmental change. However, the evolutionary trajectories of sediment-starved coasts, which are widespread worldwide, remain poorly constrained. To investigate how such coastal systems respond to relative sea-level change and tectonic activity, we examined Dongshan Bay, a typical geomorphically constrained, sediment-starved embayment on the southeastern coast of China. Multiproxy analyses of sediment core DS1, including accelerator mass spectrometry radiocarbon dating, grain-size analysis, geochemical proxies, and foraminiferal records, were integrated with a published regional relative sea-level curve to reconstruct the Holocene evolution of the bay. The results indicate three major stages. Stages I and II ( 8520–6670 cal yr BP) record the establishment and persistence of shallow-marine conditions during a period of rapid relative sea-level rise. Stage III, assigned to the interval after 6670 cal yr BP, is characterized by stratigraphic disturbance following relative sea-level stabilization and appears to reflect the combined influence of tectonic activity and episodic high-energy events. Compared with large deltaic systems, the evolution of Dongshan Bay was substantially delayed by its limited sediment supply, while regional tectonism, human activities, and catastrophic events may also have affected sediment accumulation and preservation. The evolutionary model developed for Dongshan Bay provides a valuable framework for understanding the long-term development of sediment-starved coastal systems worldwide.

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