those from the mangrove area. Quantitative estimates indicated that gray snapper from 
the seagrass area derived more than 90 %o of their carbon and nitrogen from 
sediment or water column particulate organic matter. Gray snapper from the mangrove 
area were supplied by carbon and nitrogen from these sources in addition to detritus. 
The main contributors appeared to be particulate organic matter from the water column 
and the brackish water grass, Ruppia maritima. Together, these sources accounted for 
35 to 100% of the ultimate source of prey item dietary carbon and nitrogen. These 
results suggest that within both food webs carbon and nitrogen are transferred from a 
detrital base by similar mechanisms and emphasize the use of multiple isotopes as a 
tool for quantitatively evaluating food webs. 
1983 0 
Hendrix, G. Y., and J. M. Morehead (1983) Everglades National Park: Imperiled wetland. 
AMBIQ . 20(3-4):153-7. 
[NO COPY OF PAPER AVAILABLE. ABSTRACT FROM SCHMIDT (1991).] This paper 
reports on the present status of the Everglades National Park, a wetland under fire 
from various developmental and recreational interests. A brief historical resume of the 
Park is presented including water delivery alterations, declines in wading bird 
populations and of park fisheries, endangered species protection, and invasions of 
exotic species were discussed as well as the mission of the park's South Florida 
Research Center - to monitor the effects of water management upon the ecology of the 
Everglades. 
1983 0 
Jenkins, R. V. (1983) A comparison of Florida Bay marine banks and "rock reefs' of the 
Miami Limestone in the Everglades National Park. Geol. Soc. Am. Abs. . 15(1): 1. 
[NO COPY OF PAPER AVAILABLE. ABSTRACT FROM SCHMIDT (1991).] In Everglades 
National Park, long, linear, low (0.3 m) topographic highs occur in the Pleistocene 
Miami Limestone. Morphologically similar features are accumulating today in Florida 
Bay as marine mudbanks. The origin of the 'rock reefs" has been proposed as being 
controlled by preexisting topographic features, structurally controlled, sedimentary 
depositional features, or diagenetically controlled erosional features. To learn more 
about the "rock reefs," the mud banks in Florida Bay were studied for comparative 
purposes. Significant differences in texture and grain size indicate the "rock reefs* are 
not sedimentary depositional features similar to the mudbanks. The reefs show no 
structural or topographical control. Evidence indicated the reefs are diagenetically 
controlled erosional features. 
1983 
Nelsen, J. E., and R. N. Ginsburg (1986) Calcium' carbonate production by epibionts on 
Thalassia in Florida Bay. J. Sed. Petrol. . 56:622-8. 
Annual production of lime mud by two genera of red algae and one genus of serpulid 
worms was estimated for an area of modern lime mud accumulation in eastern Florida 
Bay. The red algae Melobesia membranacea and Fosliella farinosa and the serpulid worm 
Spirobis sp. live as epibionts on the leaves of Thalassia testudinum, the extensive 
marine grass. The lime mud produced by the epibionts was estimated by quantifying: 
(1) the life span of Thalassia, (2) the abundance of Thalassia, and (3) the average 
amount of epibiont calcium carbonate per blade. The estimate also accounts for both 
aerial variations in standing crop and seasonal variations in growth rate of Thalassia. 
The estimated annual production of epibiont carbonate is 118 ± 44 g m 2 yr’ 1 , over six 
times more than the estimated production by the green alga Penicillus capitatus from 
the same area. This leads to the conclusion that the epibionts on Thalassia produce 
significant amounts of lime mud in Florida Bay. This result is close to the published 
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