development and a complex, very active phase of bank growth look place following the 
most vigorous colonization by marine grass at 2,690 BP. 14 C ages of the basal peat 
provided indication of southward progradation of the bank. 
1989 0 
Porter, D., and L. K. Muehlstein (1989) The role of fungi and slime molds in the die-back of 
Thalassia testudinum in Florida Bay. Abs., 10th Biennial Estuarine Research Conf., 
Baltimore, MD. 65. 
[ABSTRACT ONLY. NO COPY OF PAPER AVAILABLE. ABSTRACT FROM SCHMIDT (1991).] 
The wide spread die-back of turtle grass, Thalassia testudinum, in Florida Bay is 
characterized by once continuous meadows of turtle grass which have either been 
completely lost or are interspersed at frequent intervals by irregular patches of bare 
sediment. The live plants near the die-back areas have many blackened streaks and 
spots on their leaves. These necrotic regions are symptoms of a disease which may be 
a direct cause of the disease. It was found that an undescribed species of the marine 
slime mold, genus Labyrinthula, is the only eukaryotic microorganism associated with 
the necrotic leaf pieces at a much higher frequency than from green leaf pieces. The 
relationship between seagrass disease and Labyrinthula is not unexpected. A different 
species of Labyrinthula has been demonstrated to be the cause of the wasting disease of 
eelgrass, Zostera marina. 
1989 0 
Powell, G. V. N., J. G. Holmquist, and S. M. Sogard (1989) Physical and environmental 
characteristics of Florida Bay with emphasis on mud banks. Symp. on Florida Bay: A 
Subtropical Lagoon. Miami, FL. June, 1987. Bull. Mar. Sci. . 44(1):522. 
[ABSTRACT ONLY. DATE OF SAMPLING UNKNOWN OR NOT APPLICABLE.] The mudbanks 
of Florida Bay exert a disproportionate influence on the ecosystem as they represent 
most of the Bay's sediment, support half the Bay's seagrass standing crop, provide 
almost all of the Bay's wading birds' foraging habitat, and function as barriers to 
circulation, dividing the area into subenvironments. The banks were found to be 
basically flat-topped with gently sloping sides that graded into basins. The prevailing 
northeasterly winds resulted in distinct sheltered and exposed bank sides, the former 
with fine sediment and a high proportion of organics, and the high energy, exposed sides 
with coarser sediment and low organic content. Bay water levels were highest in fall. 
Lunar tidal flux was directly related to access to open ocean for any given site. Water 
levels also demonstrated some degree of wind-dependency at all sites, but particularly 
at those without pronounced lunar influence. Although water levels on narrow banks 
tracked those of basins, one 2 km-wide bank retained a lens of water at low tide. Bank 
temperatures ranged from 7.5°C to 37.0°C and demonstrated daily ranges of 4.5°C and 
up to 15°C, in contrast to basin ranges of 1.2°C. These physical characteristics shape 
Florida Bay's character by affecting plant and animal community structure and defining 
3 distinct ecological periods. The banks are the stage for complex interaction of 
physical forces. Much of this interplay would be attenuated in the deeper grassbeds that 
have been the subject of most previous studies. 
1989 0 
Robblee, M. B. (1989) Changes in benthic fauna associated with an extensive seagrass 
die-off in western Florida Bay. Abs., 10th Biennial Estuarine Research Conf., Baltimore, 
MD. 69. 
[ABSTRACT ONLY. NO COPY OF PAPER AVAILABLE. ABSTRACT FROM SCHMIDT (1991).] 
Seagrasses, principally Thalassia testudinum, have experienced extensive die-off in 
western Florida Bay since the summer of 1987. Die-off has resulted in areas of 
complete canopy loss ranging from several square meters to hundreds of hectares. In a 
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