Organic matter marshes

Peterson, B.J., Howarth, R.W., and Garritt, R.H. (1986) Sulfur and carbon isotopes as tracers of salt-marsh organic matter flow. Ecology 67, 865-874. 

Virtually anywhere water contacts organic matter in the absence of air is a suitable place for methanoarchaea to thrive—at the bottom of ponds bogs and rice fields for example Marsh gas (swamp gas) IS mostly methane Methanoarchaea live inside termites and grass eating animals One source quotes 20 L/day as the methane output of a large cow... 

Methane also is commonly produced by the decomposition of organic matter by a variety of bacterial processes, and the gas is used as a fuel in sewage plants (see Water, sewage). Methane also is called marsh gas because it is produced during the decay of vegetation in stagnant water. 

The presence of sediments in diflubenzuron marine microcosms results in rapid removal from seawater and ultimately a reduction in mortality of larval crustaceans (Table 17.2) (Cunningham et al. 1987). But marine sediments that exceed 200 pg diflubenzuron/kg — levels normally encountered at application rates for control of salt marsh mosquitoes — could be detrimental to juvenile and adult crustaceans that consume detritus and organic matter on the surface of the marsh or at the water-sediment interface (Cunningham and Myers 1986 Cunningham et al. 1987). 

Cindy Lee is a Professor at the Marine Sciences Research Center of Stony Brook University. Dr. Lee s research examines the distribution and behavior of biogenic organic compounds, in particular the rates and mechanisms of transformation reactions occurring as these compounds undergo alteration. Her research investigates organic compounds in the sediments and waters of open ocean and coastal areas, salt marshes, lakes, as well as the atmosphere above these areas. Her expertise centers on the analytical techniques used to measure organic matter in the ocean. Dr. Lee is cur-... 

AG° = -17.7kJmor at pH 7. Consequently the microbes mediating the decomposition derive less energy and produce fewer cells per unit of carbon metabolized. The accnmnlation of organic matter in marshes and peat bogs illns-trates this point. (Bnt note the rarity of tropical wetland soils with large organic matter contents, discnssed in Section 3.7.)... 

Acid-Base. The pH of natural waters is determined primarily by the carbonate equilibria. However, organisms may produce amounts of organic matter or ammonia sufficient to influence the pH and buffer capacity of the waters. It would be of interest to determine titration curves of high organic, high color, low alkalinity waters leached from some marshes. It is possible that these waters contain sufficient amounts of organic acids to be significant. 

Peterson, B. J., and R. W. Howarth. 1987. Sulfur, carbon, and nitrogen isotopes used to trace organic matter flow in the salt-marsh estuaries of Sapelo Island, Georgia. Limnology and Oceanography 32 1195-1213. 

Many of the previous direct flux measurements have focused on two distinct ecosystems, intertidal mudflats and Spartina altemiflora salt marshes. These coastal systems have the potential for large emissions of volatile reduced sulfur gases due to the availability of sulfate and organic matter. Intertidal mudflats (3.4) have a tendency towards anoxia, with concomitant production of H S via sulfate reduction. . altemiflora marshes (4T5) release DMS through the... 

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