Origin marine humic substances

A. Nissenbaum and I.R. Kaplan, Chemical and isotopic evidence for the in situ origin of marine humic substances, Limnol. Oceanogr. 17 (1972) 570-582. 

Nissenbaum and Kaplan (1972) suggest an autochthonous origin for some marine humic substances based on differences in the isotopic composition of marine and terrestrial organic matter. These two environments generally do... 

POSSIBLE ORIGINS OF HUMIC SUBSTANCES FROM MARINE... 

Compared to the well defined structures and interrelationships of the discrete molecular blomarkers and geochemical indicators discussed above, relatively little is known about marine humic substances. Whether the major source of input to dissolved and sedimentary marine humic substances is of terrigenous or marine origin is still occasionally debated in the literature, although most Interpretations point towards marine planktonic sources. (12-lA). based most convincingly on isotopic ratios, GC-MS, H and C NMR and infrared sj ctra (15-17). Stuermer et d l2) propose a combination of C and H/C ratios as a... 

Dissolved humic substances (DHS) are the main constituents of the dissolved organic carbon (DOC) pool in surface waters (freshwaters and marine waters), groundwaters, and soil porewaters and commonly impart a yellowish-brown color to the water system. Despite the different origins responsible for the main structural characteristics of DHS, they all constitute refractory products of chemical and biological degradation and condensation reactions from plant or animal residues and play a crucial role in many biogeochemical processes. 

Moran, M. A., and R. E. Hodson. 1994. Dissolved humic substances of vascular plant origin in a coastal marine environment. Limnology and Oceanography 39 762-771. 

Humic substances in marine sediments originate from both marine and terrestrial sources of organic matter, depending on the nature of sedimentary input. In some cases, a set of criteria based on chemical properties makes it possible to determine their origin. However, these criteria are less clear-cut than those established for kerogens. 

Recent advances in the structural interrelationships among humic substances of marine and estuarine sedimentary origin is discussed in the chapter by P.G. Hatcher and W.H. Orem. 

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