setipunctata contain similar concentrations of Sr, but greater concentrations of Mg and 
Fe than conspecific adults or adults of C. salebrosa. The enrichment of Mg and Fe in 
instars may be the result of rapid shell growth rate. Rapid carapace calcification may 
represent an adaptive strategy for survival that is maintained throughout the ontogeny 
of an individual. The samples were obtained from one core collected in Crab Key. 
1989 0 
Childers, D. L., J. Fourqurean, and G. V. N. Powell (1989) Intertidal seagrass banks as 
critical estuarine habitat: Evidence from a nutrient exchange study in Florida Bay, FL. Abs., 
10th Biennial Estuarine Research Conf., Baltimore, MD. 15. 
[ABSTRACT ONLY.NO COPY OF PAPER AVAILABLE. ABSTRACT FROM SCHMIDT (1991).] 
The transformation and intertidal exchange of nutrients and materials by intertidal 
seagrass banks represents an indirect habitat interaction with the associated estuarine 
water column. These processes were measured on a regularly-exposed 
Halodule/Thalassia bank in western Florida Bay over 5 tidal cycles using a 60 m 
through-low flume. Averages of significant fluxes are provided and compared with 
exchanges from flumes in Louisiana marsh systems. Fluxes from the Florida Bay 
seagrass bank were orders of magnitude greater than 1 for inorganic nitrogen, 1 - 2 
for POC and PON, and 3 for TSS. 
1989 0 
Cohen, A. D., and T. D. Davis (1989) Petrographic/botanical composition and significance of 
the peat deposits of Florida Bay. Symp. on Florida Bay: A Subtropical Lagoon. Miami, FL. 
June, 1987. Bull. Mar. Sci. . 44(1):515-6. 
[ABSTRACT ONLY. DATE OF SAMPLING UNKNOWN OR NOT APPLICABLE.] The purpose of 
this study was to develop an understanding of the early vegetation and geologic history 
of Florida Bay by analysis of the petrographic/botanical compositions of its surface and 
subsurface peat deposits. Over 600 sites were investigated, of which 134 were found 
to contain some peat. Most of these peat deposits were basal layers overlain by marine 
carbonate-rich marls. A representative selection of these peat deposits was sampled 
and analyzed using piston coring and microtome-sectioning procedures. Peat types 
representing 13 different autochthonous depositional environments were identified. 
Three of these represented marine, mangrove-dominated settings ( Rhizophora Peat, 
Rhizophora-Avicennia Peat, and Avicennia Peat); two were transitional settings 
(Rhizophora Transitional Peat and Conocarpus Transitional Peat); and eight represented 
freshwater settings ( Mariscus [Cladium ]) Peat, Acrostichum-Mariscus Peat, 
Mariscus-Sagittaria Peat, Mariscus-Nymphaea Peat, Mariscus-Cephalanthus Peat, 
Cephalanthus Peat and Myrica-Persea-Salix Peat). The primary micropetrographic 
parameters used in defining each of the peat types and in reconstructing its 
environment of deposition were the abundances and types of: (1) botanically identifiable 
plant fragments; (2) plant decomposition products; (3) animal remains (such as sponge 
spicules, radiolaria, foraminifera, shell fragments and insect parts); and (4) mineral 
components (such as carbonates and pyrite). The identification of the freshwater peat 
types in all sites analyzed were especially significant because these types represent 
depositional settings that do not occur in Florida Bay today but are, however, presently 
forming on the mainland Everglades. The petrograph botanical evidence thus supports an 
hypothesis that the peat deposits of Florida Bay represent erosional remnants of a more 
extensive area of freshwater Everglades-type peat that occupied portions of the region 
before it was converted to Florida Bay by a transgressing sea. 
1989 0 
Cottrell, D. J. (1989) Holocene evolution of the coast and nearshore islands, northeast 
Florida Bay, Florida. Ph. D. Dissertation. University of Miami, Coral Gables, FL. 194 pp. 
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