9.1.7.2.3. Evapotranspiration measurements and modeling 
Although evapotranspiration is a major component of the Everglades water budget, few 
measurements have been made for the variey of land-cover environments characteristic of the 
region. This project installed instrumentation at 8 sites in a variety of environmental settings 
and will develop field measurements of evapotranspiration based on a process-oriented model. 
Data developed at the eight sites was used to extrapolate areal evapotranspiration values for 
use in the hydrologic model relied on by all federal and state agencies to plan Everglades 
restoration. 
9.1.7.2.4. Elevation data 
Modeling of sheet flow and surface water stage are highly sensitive to land-surface elevation 
data which are poorly defined throughout much of the flat terrain of South Florida. Using new 
GPS technology made available by NOAA, elevation data with an accuracy of better then 0.5 ft 
were obtained in critical areas. These data improved the performance of hydrologic models and 
also provided useful ancillary data for biologic studies planned by federal and state agencies. 
9.1.7.2.5. Groundwater flow beneath Conservation Area 3B levee 
A major component of Everglades restoration is the maintenance of higher water levels in 
Conservation Area 3B and construction of a flow way between the levee and the adjacent urban 
area. Uncontrolled groundwater flow beneath the levee had not been measured but was 
estimated to be as much as 30% of the outlfow from the conservation area. A combination of 
surface water measurments and groundwater modeling provided improved estimates of leakage 
beneath the levee and improved the calibration and predictions of regional hydrologic models. 
9.1.7.2.6. Open channel and wetlands flow transport 
Linkage of models depicting flow within various hydrologic components of the Everglades flow 
system is needed to better understand and simulate the movement of nutrients. This project 
developed a model to simulate fluid-driven mass and a constituent transport in canals, 
groundwater, and wetlands (sheet flow). 
9.1.7.3. Everglades water quality 
9.1.7.3.1. Mercury accumulation and cycling 
Although considerable monitoring of Hg in water, sediments and fish was done in South Florida, 
only limited work was done to understand the processes by which Hg enters the food chain. This 
project determined the effect that various environmental factors, such as levels of dissolved 
organic C, nutrients, S, and hydrologic conditions, have on transport, sedimentation, 
volatilization, and methylation of Hg. 
9.1.7.3.2. Geochemical processes in organic-rich surficial sediments 
To an unknown but potentially significant degree, the concentrations of dissolved elements such 
as C, P, N, and trace and heavy metals, are controlled by chemical and biochemical reactions 
occurring in the peat and other organic-rich soil underlying much of the Everglades. This 
project looked at regional geochemical processes and trends as well as the effect of alternating 
periods of wetting and drying. 
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