Developing Benthic Class Specific, Chlorophyll-a Retrieving Algorithms for Optically-Shallow Water Using SeaWiFS.

This study evaluated the ability to improve Sea-Viewing Wide Field-of-View Sensor (SeaWiFS) retrieval from optically shallow coastal waters by applying algorithms specific to the pixels' benthic class. The form of the Ocean Color (OC) algorithm was assumed for this study. The operational atmospheric correction producing Level 2 SeaWiFS data was retained since the focus of this study was on establishing the benefit from the alternative specification of the bio-optical algorithm.

Modeling the impact of restoration efforts on phosphorus loading and transport through Everglades National Park, FL, USA.

Ecosystems of Florida Everglades are highly sensitive to phosphorus loading. Future restoration efforts, which focus on restoring Everglades water flows, may pose a threat to the health of these ecosystems. To determine the fate and transport of total phosphorus and evaluate proposed Everglades restoration, a water quality model has been developed using the hydrodynamic results from the M3ENP (Mike Marsh Model of Everglades National Park)--a physically-based hydrological numerical model which uses MIKE SHE/MIKE 11 software.

Fenton treatment of landfill leachate under different COD loading factors.

The application of Fenton treatment technology for treatment of landfill leachate greatly depends on the optimum Fenton operating conditions for a specific leachate. Determining optimum Fenton conditions requires multiple experiments using variable reaction parameters (pH, temperature, and H2O2 and Fe(2+) doses) and previous researches show a wide range of optimal operating conditions. In this study, the applicability of the dimensionless loading factor (LCOD), which is defined as the initial COD (COD0) of leachate with respect to available O2 for oxidation, was examined to derive optimum Fenton oxidant dose using reduced set of experiments.

Estimation of the major source and sink of methylmercury in the Florida Everglades.

Mercury methylation and/or demethylation have been observed in several compartments [soil (saturated soils covered by standing water), floc, periphyton, and water] of the Everglades, a wetland with mercury as one of the major water quality concerns. However, it is still unclear which compartment is the major source or sink due to the lack of estimation and comparison of the net methylmercury (MeHg) production or degradation in these compartments. The lack of this information has limited our understanding of Hg cycling in this ecosystem.

Dispersion and stability of bare hematite nanoparticles: effect of dispersion tools, nanoparticle concentration, humic acid and ionic strength.

The aggregation and sedimentation of iron oxide nanoparticles (IONPs) can significantly affect the mobility and reactivity of IONPs and subsequently influence the interaction between IONPs and environmental contaminants. Dispersing bare IONPs into a stable suspension within nanoscale range is an important step for studying the interaction of IONPs with contaminants (e.g.

Degradation of methylmercury and its effects on mercury distribution and cycling in the Florida Everglades.

Methylmercury (MeHg) is recognized as one of the major water quality concerns in the Florida Everglades. Degradation of MeHg in the water is thought to be one of the most important processes to the cycling of MeHg, but there is a lack of quantitative estimations of its effect on the distribution and cycling of MeHg in this ecosystem. Stable isotope (Me201Hg) addition method was implemented to investigate the degradation of MeHg in the Everglades.

Spatial variability in mercury cycling and relevant biogeochemical controls in the Florida Everglades.

Spatial patterns in mercury cycling and bioaccumulation at the landscape level in the Everglades were investigated by collecting and analyzing multimedia samples for mercury species and biogeochemical characteristics from 228 randomly located stations. Higher total mercury (THg) in environmental compartments (surface water, soil, flocculent detrital material (floc), and periphyton) generally occurred in the northern and central Everglades, but higher THg in water and periphyton in the Everglades National Park was an exception. Multiple biogeochemical characteristics, such as surface water dissolved organic matter (DOC(sw)), pH, chloride, and compositional properties of solid compartments (soil and floc), were identified to be important factors controlling THg distribution.