tract and the more normal marine portions of Florida Bay. Vertical advection of 
particles by their burrowing and feeding behavior coupled with storm infilling of their 
burrows represents a major pathway for large-scale particle and pollutant transport. 
1994 0 
Tomasco, D. A., B. E. Lapointe (1994) An alternative hypothesis for the Florida Bay 
seagrass die-off. Bull. Mar. Sci. . 54(3): 1086. 
[ABSTRACT ONLY. DATE OF SAMPLING UNKNOWN OR NOT APPLICABLE.] A large die-off 
of the subtropical seagrass Thalassia testudinum has recently occurred in Florida Bay. 
Currently, it is the belief of many researchers that human activities other than 
freshwater divergence had little role in the initiation of this die-off. Elevated salinities 
(>50 °/oo) and water temperatures are thought to be involved with die-off. Previous 
work indicates that T. testudinum has an optimum salinity of about 30 °/oo, with 
reductions in productivity above and below this level. However, when the die-off areas 
are overlain on salinity isopleths it is apparent that die-off areas are not centered 
around areas of highest salinities. In Laguna Madre, a negative estuary similar to 
Florida Bay, Thalassia testudinum is found in areas with salinities above 40 - 45 %o, 
well above values found in most (not all) areas of die-off in Florida Bay. It is the belief 
of the authors that there is little evidence that suggests high salinities were important 
in bringing about the die-off of T. testudinum in Florida Bay, as has been previously 
suggested. Therefore, not only would reestablishment of historical freshwater flows 
into northeast Florida Bay increase nutrient loads into that area (due to anthropogenic 
nutrient enrichment of discharged water), there is not much promise that this activity 
would lessen the chance of later seagrass die-offs. However, high temperatures 
(perhaps related to high water column chlorophyll levels) might be an important 
component to die-off. What seems more clear is that areas of Florida Bay that 
experienced later die-off are characterized by higher biomass than areas where die-off 
did not occur. In addition, these areas of already high biomass had experienced recent 
large increases in above ground biomass prior to die-off. This leaves the question of 
how did such an increase in biomass occur? A review of the literature suggests two 
ways to bring about an increase in seagrass biomass: increase the available light, and 
increase the sediment nutrient supply. This paper will address the potential role of both 
increased light levels and increased sediment nutrient levels in triggering the die-off of 
Thalassia testudinum in Florida Bay. 
1994 0 
Wang, J. D. (1994) Circulation in Florida Bay. Florida Coastal Ocean Sciences Symp. April 
1994. University of Miami, Miami, FL. 42. 
[ABSTRACT ONLY. DATE OF SAMPLING UNKNOWN OR NOT APPLICABLE.] Surface 
elevation and salinity data obtained from the Marine Monitoring Network of the 
Everglades National Park were used to explore the causal relationships between 
forcings and hydrodynamic response in Florida Bay. Astronomical tides entering the 
Bay from the Gulf of Mexico are primarily diurnal. The tides are strongly damped as 
they move eastward into the Bay. Model analysis indicates that the damping is 
primarily due to the horizontal constrictions imposed by mudbanks and islands, although 
bottom friction in the shallow depths of the Bay is also important. Associated with the 
damping of the tidal waves is a mean sealevel setup which has been estimated to be 
about 1 to 2 cm. It is plausible that this mean sealevel setup gives rise to a net flow out 
of the Bay to the south, through the passes between the Florida Keys. The Bay's 
hydrodynamic response appears to be dominated by three time scales. The astronomical 
tides, 1/2 to 1 day; seabreeze, 1 day; winter winds, 3 to 4 days; and 14 day lunar 
tidal components. Much of the wind response appears to be due to propagation of coastal 
sea level changes on the West Florida Shelf into Florida Bay. The energetics of the long 
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