Molecular composition marine organic matter

Guo, L., Tanaka, N., ScheU, D. M., and Santschi, P. H. (2003). Nitrogen and carbon isotopic composition of high molecular weight dissolved organic matter in marine environments. Marine... 

McCarthy, M., J. I. Hedges, and R. Benner. 1996. Major biochemical composition of dissolved high molecular weight organic matter in seawater. Marine Chemistry 55 281-298. 

As discussed in Section V, the spectrum of substrates and substrate proxies currently used to measure enzyme activities in marine systems is limited and most likely does not adequately represent the macromolecules actually available to aquatic microbial communities. Despite progress in recent years, our knowledge of the molecular structure and composition of dissolved organic matter is still only rudimentary. Although carbohydrates constitute an estimated 25-50% of DOC in seawater (Benner et al., 1992),... 

McCarthy, M. D., Bronk, D. A., In press. Analytical methods for the study of nitrogen. In nitrogen in the marine environment (Capone, Bronk, MulhoUand, Carpenter, eds.). Elsevier, San Diego, CA. McCarthy, M., Hedges, J. L, and Benner, R. (1996). Major biochemical composition of dissolved high molecular weight organic matter in seawater. Marine Chemistry 55(3-4), 81-297. 

A comparison of organic matter (OM) components in cores from Dabob Bay (oxic bottom waters) and Saanich Inlet (anoxic bottom waters) indicates that 02 availability ultimately has little or no independent effect on OM preservation in these environments (Cowie Hedges, 1992). Comparative analyses of organic compounds in sediment traps and bottom sediments from Saanich Inlet indicates that the anoxic benthic interface is an important site of diagenesis, and that selective removal takes place at both compound-class and molecular levels (Cowie etal., 1992). Preferential loss of marine organic material is indicated by the calculated delta-C-13 value and biochemical composition of the substrate. 

The simplest way of describing the ehemieal nature of biomass is by its elemental composition. For marine phytoplankton as primary producers a relationship was found to the nutrients available in seawater whieh led to the definition of the Redfield ratio as C N P = 106 16 1 (Redfield et al. 1963). Derived from this is an average molecular formula of phytoplankton organic matter related to the general process of phytosynthesis (of which the reverse signifies remineralization) ... 

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