Algal Sources of Dissolved Organic Matter

FIGURE 1 Fate and major transformation pathways of phytoplankton- and macrophyte-derived DOM in aquatic systems. Arrows indicate fluxes POC denotes particulate organic matter LMW and HMW DOM refer to the monomeric (low molecular weight) and polymeric (high molecular weight) fractions, respectively. 

Pathways for Algal Dissolved Organic Matter Production 

The vast majority of studies assessing the quantity of extracellularly released organic compounds from primary producers have relied on different experimental protocols based on the 14C-tracer technique developed to measure photosynthesis in marine waters (Steeman-Nielsen, 1952). Using this technique, the extracellular DOM release by phytoplankton has been studied in both pure cultures and natural water samples. From pure culture 

TABLE I Selected Reports of Percentage Extracellular Release (PER) of Photosynthetically Fixed Carbon in Cultures, Freshwaters, and Marine Waters 

Chemical Composition of Algal-Derived Dissolved Organic Matter 

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