closes with an excellent list of references that can serve as a starting 



place for anyone wishing to make a survey of the value of tidal marshes. 

 (J.B.) 



Keywords: productivity, detritus, food chain, coastal waters, Mississippi 



II-A-6 



Odum, E.P. 1961. The role of tidal marshes in estuarine production. 

 The Conservationist 15(June-July) :12-15. 



This is an excellent, early introduction to the value of coastal 

 marshes that discusses primary production and detritus utilization on 

 the basis of the pioneering studies by the University of Georgia Marine 

 Institute at Sapelo Island. Odum points out that marsh productivity is 

 based on the three separate vegetation regimes: (1) the vast areas 

 of Spartina or cord grass marshes; (2) the benthic or mud algae that 

 grows throughout the intertidal sediments, but especially on the creek 

 banks, and (3) the phytoplankton in the water. Comparisons are made 

 between marsh lands and other land and water areas. Because marsh 

 areas are highly productive, emphasis should be placed on utilization 

 as they are rather than on transformation for other forms of production. 

 Much more needs to be learned about how energy flows in the system, 

 which is extremely complex, partly because the three primary crops 

 produce different consumer energy flows. Because of the great importance 

 of exports and imports and the diversity of production and consumption 

 units, the entire estuarine system must be considered as a whole. 

 The paper emphasizes the need for differential development criteria 

 for high, low, and intermediate marshes. (J.B.) 



Keywords: productivity, detritus, coastal marsh, salt marshes value, 

 Georgia 



II-A-7 



Schelske, C.L., and E.P. Odum. 1962. Mechanisms maintaining high 



productivity in Georgia estuaries. Proceedings of the Gulf and Caribbean 



Fisheries Institute 14:75-80. 



The productivity of estuaries, as well as the productivity of most 

 ecosystems, is essentially dependent on the rate of primary productivity 

 within the system or, in other words, on the amount of organic material 

 formed as the result of photosynthesis. Heterotrophic organisms, like 

 man, are dependent on green plants for food supply. Therefore, the 

 high productivity of estuaries is really a function of the rate of plant 

 growth. 



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