Controls on the accumulation of low molecular weight dissolved organic matter in estuarine and coastal sediment porewaters

In this study, we analyzed the concentrations of dissolved organic carbon (DOC), the optical absorption and fluorescence properties of chromophoric dissolved organic matter (CDOM) in surface and bottom waters, and sediment porewaters, in the Pearl River Estuary and adjacent Coasts (PREC) in December 2021 and April 2022. The overarching objective of this study was to examine the spatial and temporal variations, as well as the controlling mechanisms, of the concentrations, sources and composition of DOM in the PREC.