Seasonal Variation, Degradation, and Bioavailability of Dissolved Organic Matter in the Changjiang Estuary and its Adjacent East China Sea

Abstract

Dissolved organic carbon (DOC) in the sea is primarily removed by heterotrophic prokaryotes (Azam, 1998). However, Hansell and Carlson (1998) estimated that 17% of global new production escapes rapid utilization by microbes and accumulates as DOC in surface waters. Previous field observations from the Bermuda Atlantic Time-Series Study (BATS) site demonstrated that semilabile DOC in the upper euphotic zone was less available to microorganisms and remained at constant concentrations in stratified water column (Carlson et al., 2002; Hansell & Carlson, 2001). Depending on the marine system, temperature, grazing, and competition for limited nutrients might restrict bacterial production (Rivkin & Anderson, 1997; Shiah &

Air‐Sea Gas Exchange and Its Potential Influence on the Regional Fate of Polycyclic Aromatic Hydrocarbons in the East China Marginal Sea

“…16 (Schwarzenbach et al., 2003). [DOC] in surface water of research area was determined by previous field study about distribution of DOC (He et al., 2006; Ji et al., 2021; Wang et al., 2019).…”

Source, distribution, and transformation of dissolved and particulate organic matters in Qinzhou Bay, Northern Beibu Gulf

“…Unlike the dominance of dissolved OM (DOM) in reduced carbon pools of open ocean (Gardner et al, 2006, Hansell et al, 2009, particulate OM (POM) accounts for a considerable proportion of total OM in coastal regions due to large external inputs and substantial in situ phytoplankton production (Ji et al, 2021). Focusing on either the DOM or POM in coastal regions, with respect to its composition, sources, and sinks has led to them to being well understood, largely by applying key techniques such as elemental analyses, isotopic data and analysis (Sarma et al, 2014;Huang et al, 2020), optical properties (Stedmon et al, 2000, Guo et al, 2014, and molecular characterization (Wu et al, 2022).…”