Particulate Organic Carbon Cycling and Transformation

Abstract

This chapter provides a general background on the sources, transformation, and transport of particulate organic carbon (POC) in estuarine and other coastal systems. It begins with methods of POC quantification and extraction. This is followed by a section on sources of POC in these dynamic systems, which extends across terrestrial, estuarine, and marine sources. More emphasis has been placed on POC sources from primary production rather than secondary production, and the complexity of trophic dynamics is covered elsewhere in this treatise. Bulk characterization of POC using spectroscopic techniques (e.g., stable isotopes and nuclear magnetic resonance spectroscopy) and other methods is then discussed followed by a more molecular approach using chemical biomarkers in combination with compound-specific isotope analyses. Compositional information about POC is then interfaced with its effects on decay rates of different detrital sources. Transport of POC within estuarine systems and in large river coastal environments is also discussed here. Finally, the chapter concludes with examples of POC budgets in some well-studied estuarine systems along with some summary remarks and some future directions.