Such biological agents and their countless allies alter the chemical 

 and physical nature of both water and floor, not only near the coast 

 but at considerable distances out from shore. (Author's summary and H.D.) 



Keywords: detritus, marine invertebrates, inshore animals 



III-E-18 



Marples, T.G. 1966. A radionuclide tracer study of arthropod food chains 

 in a Spartina salt marsh ecosystem. Ecology 47:270-277. 



The arthropods of the Spartina marsh obtain their energy either 

 by grazing on the marsh grass or by eating the microbial -rich organic 

 detritus that is largely derived from the dead Spartina . The two 

 energy sources were labeled with phosphorus in separate quadrats and 

 the subsequent buildup of radioactivity followed in the arthropod 

 populations. Four species of insects were dominant grazing organisms 

 (one Orthoptera, two Hemiptera, and one Homoptera), while two families 

 of Diptera (Dolichopodidae and Ephydridae) included the important 

 insects associated with the detritus complex. The spiders were the 

 important carnivores and obtained their energy from both the detritus 

 and grazing food chains. (A. A.) 



Keywords: arthropods, food chain, Spartina , salt marsh ecosystem, 

 detritus 



III-E-19 



Reeve, M.R. 1975. The ecological significance of the zooplankton in the 



shallow subtropical waters of south Florida. Pages 352-371 iji L.E. Cronin, 

 ed. Estuarine research. Vol. 1. Academic Press, New York. 



Much emphasis has been placed on the imported detrital and benthic sea 

 grasses in the biological economy of shallow subtropical inshore waters. 

 This report seeks to present the existing data on plankton, which indicate 

 that the shallow water column may support planktonic production at 

 least as large as some much deeper, colder-water, inshore regions. 

 It is suggested than plankton organisms are important in the utilization 

 of this material in the marine ecosystem both by their rapid uptake 

 of dissolved organics flushed out from the land and released from 

 sediments and by the possible ability of the ultra-microzooplankton 

 to graze on detrital -bacterial aggregations in the water column. 

 In two adjacent areas substantial differences in plankton biomass 

 could be correlated with freshwater runoff. In the low biomass 

 region, summer temperatures were associated with severe depressions of 

 macroplankton populations. (A. A.) 



Keywords: zooplankton, productivity, estuarine systems, detritus, 

 Florida 



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