1979 0 
Wanless, H. R. (1979) Role of physical sedimentation in carbonate-bank growth. Am. Assoc. 
Petrol. Geol, Bull. . 63(3):547. 
[ABSTRACT ONLY. DATE OF SAMPLING UNKNOWN OR NOT APPLICABLE.] Carbonate 
mudbanks of central Florida Bay contain three types of sediment wedges which provide 
evidence that pulses of rapid physical sedimentation are a dominant cause for bank 
growth and migration. Most dramatic are layered to laminated wedges of carbonate 
mudstone flanking eastern, southern, or western bank margins . Depositional units are 
.5 to 1.5 m thick and compose up to 70% of the existing bank. Units have erosional 
basal contacts: basal shelly sand grades upward to a layered laminated mudstone 
containing no pellets, no burrowing, no seagrass rootlets, and few sand size skeletal 
grains. Three features suggest rapid disposition: vertical escape burrows extending 
upward from the basal sand, vertical smooth-walled water escape fractures in the 
lower part, and abundant seagrass blades incorporated into the layers. The second type 
of wedge is a layered, pelleted mudstone to packstone otherwise similar to that 
described above. The third type of wedge is a bioturbated, soft-pellet wackestone to 
packstone as much as 1 m thick and flanking only southern bank margins. It contains 
horizontal to inclined seagrass rhizomes throughout and has minor autochthonous 
mollusks. The layered wedges are interpreted to record rapid sudtidal sedimentation 
during rare super storms (extreme hurricanes), the first type from storms of 
sufficient violence to destroy most pellets. The third wedge type records persistent 
lee-side accumulation from lesser hurricanes and winter storms. This deposition, 
although rapid, is slow enough to be in continuous association with a seagrass- 
community influence. 
1979, 1983 - 1984 
Zieman, J. C., J. W. Fourqurean, and R. L. Iverson (1989) Distribution, abundance and 
productivity of seagrasses and macroalgae in Florida Bay. Symp. on Florida Bay: A 
Subtropical Lagoon. Miami, FL. June, 1987. Bull. Mar. Sci. . 44(1 ):292-311. 
The distribution, abundance, and productivity of submerged macrophytes were 
measured in Florida Bay to determine the total productivity and seagrass habitat 
distribution throughout the region using aerial photography and ground verification, 
benthic community characterization, 14 C uptake studies, drift material sampling and 
other techniques. The field work took place during 1983 and 1984 except for the drift 
material sampling which took place in 1979. The sediment, water level and water 
temperature at these locations was described by Holmquist et al. (1989) and the 
decapod and stomatopod communities by Holmquist et al. (1989). Thalassia testudinum 
was widely distributed and was the dominant macrophyte species in the 1,660 km 2 of 
seagrass beds contained in the bay. Halodule wrightii was also common, but had 
standing crop significantly less than Thalassia at all sample locations. Syringodium 
filiforme grew mainly in areas with strong oceanic influence, especially along the south 
and west margins of the Bay. Macroalgae were a small percentage of the total 
macrophyte biomass. Gradients in environmental and biological variables extended from 
southwest to northeast Florida Bay. Water clarity, water exchange, and sediment depth 
were all greatest in the south and west portion of the bay and decreased towards the 
northeast corner of the bay. The seagrass standing crop varied from between 60 and 
125 g dw m‘ 2 in the southwest to between 0 and 30 g dw m‘ 2 in the northeast. Total 
seagrass leaf standing crop was 8 x 10 10 g dw in Florida Bay, 90% of which was 
Thalassia leaf material. Thalassia mean leaf productivity was 0.97 g dw nr 2 d‘\ with 
higher values in the southwest and lower values in the northeast portions of the bay. 
Approximately I .7 x 10 9 g dw d' 1 of Thalassia leaf tissue was produced in Florida Bay 
during the summer. Thalassia had about the same leaf productivity on a per gram leaf 
dry weight basis throughout the different environments of Florida Bay, therefore 
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