<p>Both natural and human-induced disturbances affect the normal functioning and services of mangrove ecosystems. To address the consequences of intense human and climatic disturbances on sedimentation and carbon burial, sediment cores from the last remaining mangrove <i>Kandelia obovata</i> forest and an adjacent mudflat in the densely populated and typhoon-prone Zhujiang (Pearl) River estuary of China, were analyzed using methods including ²¹⁰Pb dating and δ¹³C analysis. Results indicate that after damming in the 1950s, during 1960–1980, the natural establishment of <i>K. obovata</i> forests initiated the in-situ sedimentation. As these forests matured during 1980–1990, they significantly boosted siltation in the region on mudflat. During 1990–2015, the invasion of <i>Spartina alterniflora</i> and land reclamation for aquaculture caused infiltration of coarse sediments and the impacts of typhoons were recorded within the <i>K. obovata</i> forest, while no clear typhoon record was observed on the mudflat. Since 2015, reforestation efforts with <i>S. apetala</i> that began in 1999 have reversed the effects of earlier deforestation. Over time, mangroves established a rapid autochthonous carbon burial that grew as the forests age, potentially surpassing the influx of allochthonous carbon due to deforestation. The reforestation also immediately improved carbon burial on the mudflat, which stabilized after a decade due to the rapid growth and high biomass of <i>S. apetala</i>. Overall, the <i>K. obovata</i> forest demonstrated a stronger sedimentation and carbon burial capabilities than the mudflat, with a surplus of 35.2 Mg C/hm² in soil organic carbon stock and 1.0 Mg C/(hm²·a) in burial rate. Organic matter dissolved in soil was mainly humus-like components, and mangrove inputs likely increased the degree of humification. This study offered direct evidence regarding the impact of multiple disturbances on local and regional sedimentation and carbon burial, and future management strategies.</p>