2 

 filter-feeding animals, approximately 300 g C/m water surface/year 

 was estimated for export from the estuary or deposition in sediments. 

 (G.S.) 



Keywords: productivity, detritus, carbon, estuary, Louisiana 



III-D-2 



Allen, R.L. 1975. Aquatic primary productivity in various marsh environments 

 in Louisiana. M.S. Thesis, Louisiana State University, Baton Rouge. 50 pp. 



Dissolved oxygen, total organic carbon, dissolved organic carbon, 

 and chlorophyll a^ were measured from September 1973 to August 1974 at 

 both natural and altered stations along a north-south transect which 

 crossed all major marsh environments characteristic of south Louisiana. 



Organic carbon was statistically related to net community production, 

 but not to gross production, supporting the idea that marsh-bordered 

 estuaries are detritus-based. In addition, there was a significant 

 correlation between gross production and chlorophyll levels. Net 

 community production, TOC, and DOC were highly related with chlorophyll. 



The study area did not demonstrate a strong seasonal trend in productivity, 

 a condition that is often evident in higher latitude temperate estuaries. 

 Seasonal production rates tended to be erratic, largely because of the 

 semi tropical climate that prevails in southern Louisiana. Rates were 

 found to be generally higher in the summer, with occasional phytoplankton 

 blooms. There was a strong correlation between water temperature 

 and productivity. (L.H.) 



Keywords: primary productivity, marsh environments, Louisiana 



III-D-3 



Heinle, D.R., D.A. Flemer, J.F. Ustach, and R.A. Murtagh. 1975. Contributions 



of tidal wetlands to estuarine food chains. Maryland Water Resources 



Research Center, College Park, Technical Report No. 29. 



The flows of detritus and nutrients from stable marshes in the upper 

 Patuxent estuary subjected to low tidal amplitude were slight. The 

 quality of particulate carbon flowing from the marsh to the estuary 

 was less than 10 percent of annual production. By contrast, a portion 

 of the marshes subjected to scouring by ice lost virtually all of its 

 aboveground biomass to the estuary and contributed over half of the 

 annual carbon budget to the system. (J.B.) 



Keywords: productivity, detritus, algae, estuary, Maryland 



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