Wetland resources in South Florida are regulated at three redundant jurisdictional levels: local or municipal regulations set forth by many independent jurisdictions, State regulations derived directly from Florida Statutes, and Federal regulations promulgated primarily under the Clean Water Act. All three levels of government can have jurisdiction over projects that affect regulated wetland resources, yet inconsistent policies and standards remain and continue to confound regulators despite decades of intensive coordination efforts and a rapidly growing scientific research base. The size of a wetland mitigation area is of primary consideration when evaluating its perceived ecological value, although wetland mitigation areas constructed in developed areas are typically isolated and generally make use of similar designs regardless of wetland size. The Chironomidae (Order: Diptera) are the most diverse and abundant faunal taxon in all healthy freshwater bodies and are generally considered to be a reliable and effective ecological indicator. I conducted a preliminary comparison of chironomid communities between a suite of natural and artificial wetlands, and also evaluated the effect of wetland size on the community structure of the insect family Chironomidae. Using the Chironomid Pupal Exuviae Technique (CPET), collections of chironomid exuviae from a total of seven natural and artificial mitigation wetlands were compared across site groups and also correlated to recorded environmental conditions at each study site. Chironomid species assemblages at nearly all sites were dominated by Parakiefferiella coronata, comprising nearly 36% of all collected exuviae. Species assemblages from mitigation wetlands exhibited strong similarity to the aggregate species assemblage from all sites. A greater abundance of exuviae was collected from artificial sites than from natural sites, and species assemblages collected from natural sites were dissimilar from those collected from artificial sites. No statistically significant differences in community structure were detected between larger and smaller wetlands. Environmental site conditions between natural and mitigation sites generally varied greatest in conductivity and pH. No significant gradient was identified in environmental conditions or chironomid community structure across wetlands of different size. A minor seasonal gradient in TP concentrations was observed and site S6 was the most enriched site included in this study while site S1 exhibited high conductivity for the duration of the project. Differences between chironomid species assemblages collected from natural and artificial communities may be explained by the relatively static topography, more consistent substrate composition, and less diverse hydrophyte communities present in the natural sites which have generally reached a greater state of homeostasis. However, statistical tests generally support the null hypothesis. No statistically significant differences were detected between sites based on collected chironomid communities when grouped by wetland origin (artificial vs. natural) or size. Observed differences between communities sampled from natural and artificial wetlands support regulatory concerns that artificial wetlands may not sufficiently emulate natural systems and that a constructed wetland system may take generations, or even centuries to sufficiently mimic its natural counterpart. Mitigation design complexity does appear to provide a diversity of microhabitats favorable to a greater variety of chironomids. However, a lack of statistical significance may support assertions that mitigation sites are successfully replacing natural wetlands. Implementation of CPET-based community structure analyses requires intensive labor and expertise and is not practical for regulatory purposes, but can provide robust data for effective and detailed site analysis.

The diurnal movements of Florida manatees (Trichechus manatus latirostris) in warmwater refugia are poorly understood and these may prove critical in accurately estimating populations of these animals. Previous studies indicate that manatee populations in such refuges in Tampa Bay, FL, peak mid-day and decline towards evening when the animals leave to forage. This trend suggests that variation in the timing of aerial manatee population surveys may hamper accurate estimation of the true population size. Aerial survey counts are known to underestimate population size, yet the extent of the underestimation may be greater than expected. In this study data were collected over three seasons from land-based surveys monitoring the presence of manatees in the effluent canal from the Florida Power and Light electricity generating facility in Port Everglades, FL between 15 November and 31 March. My findings indicated there was no significant difference in the number of manatees observed during the seasons studied despite a significant difference in ambient water temperatures. There was a significant correlation in the number of manatees an observer can expect to see based on time of day with the trend indicating there are higher numbers of observable manatees in the morning compared to later in the day. This suggests that early morning aerial counts will more accurately reflect true manatee presence in the Port Everglades power plant. Photographs of individual manatees yielded a total of 58 animals with unique scaring patterns.

Peatlands cover a total area of approximately 3 million square kilometers and are one of the largest natural sources of atmospheric methane (CH4) and carbon dioxide (CO2). Most traditional methods used to estimate biogenic gas dynamics are invasive and provide little or no information about lateral distribution of gas. In contrast, Ground Penetrating Radar (GPR) is an emerging technique for non-invasive investigation of gas dynamics in peat soils. This thesis establishes a direct comparison between gas dynamics (i.e. build-up and release) of four different types of peat soil using GPR. Peat soil blocks were collected at peatlands with contrasting latitudes, including the Everglades, Maine and Minnesota. A unique two-antenna GPR setup was used to monitor biogenic gas buildup and ebullition events over a period of 4.5 months, constraining GPR data with surface deformation measurements and direct CH4 and CO2 concentration measurements. The effect of atmospheric pressure was also investigated. This study has implications for better understanding global gas dynamics and carbon cycling in peat soils and its role in climate change. / by Anastasija Cabolova. / Thesis (M.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.

Environmental perturbations are ubiquitous features of ecosystems and shape ecological structure and function. Climate change will alter the intensity and frequency of disturbances and expose ecosystems to novel combinations of useful inputs (subsidies) and harmful inputs (stressors). Coastal wetlands are particularly vulnerable to changing environmental conditions and are increasingly exposed to effects of interacting subsidies and stressors. In particular, the Florida Coastal Everglades, which has experienced accelerated change due to a history of water management practices, is vulnerable to new disturbances associated with climate change. The low-lying Florida Everglades faces multiple disturbances from storm surge, nutrient enrichment, and sea-level rise which will influence its responses to future environmental perturbations. Microbial communities are often used to characterize environmental change because of their high surface area to volume ratio, permeable membrane, and quick turnover rates. Therefore, assessing how microbial function changes can provide insights into how subsidies and stressors interact to alter biogeochemical cycles. I tested how nutrient enrichment can alter ecosystem responses to stress and found that it did not promote recovery in mangrove plants. I examined how long-term exposure to salinity and phosphorus (the limiting nutrient in the Everglades) affected microbial enzyme activity and found that salinity alone acts as a suppressor of enzyme activity but phosphorus addition can mitigate salinity stress in sawgrass soil. I tested how pulses of salinity can affect the microbially-mediated breakdown of organic material and found that the microbial community was functionally redundant and unaffected by saltwater pulses; however, microbial activity was consistently lower in the brackish marsh compared to the freshwater marsh. I investigated how gradients of salinity and phosphorus affected freshwater and brackish soils and determined previous exposure to saltwater intrusion dominates affects microbial function and soil composition. Across these experiments, I found that environmental perturbations alter the microbial-mediated processing of nutrients and carbon, and legacies of previous disturbances influence the microbial response to new disturbance regimes.

The Forgiveness Project includes a critical introduction that defines the author’s approach to the short-short form as well as an explanation of how historiographical metafiction can work to memorialize. The first section contains primarily short-short stories that address the themes of motherhood, small tyrannies, happy liars, caregiving and the clichés of grief. A collection of linked short stories follows, revolving around elusive forgiveness. On the night of July 17, 1977, Juanita Lee, a bridge tender in South Florida, was abducted by two men and executed in the Everglades to silence her opposition to the demolition of an Intracoastal Waterway bridge. Twenty-two years later her daughter, Jill, now a Washington D.C. lobbyist who views the world through the cynical lens of her life’s work, is confronted with a plea for forgiveness via an organization called “The Forgiveness Project,” representing one of her mother’s killers.

Thesis (M.S.)--Oregon State University, 2002. / Typescript (photocopy). Includes bibliographical references (leaves 88-91). Also available on the World Wide Web.

The seasonal distribution of the Florida manatee (Trichechus manatus latirostris) is influenced predominantly by feeding locations in the summer and proximity to warm-water refuges during colder months. Due to their limited ability to tolerate cold water, when water temperatures drop below 20°C manatees congregate around natural and artificial warm-water refuges, such as warm-water springs or power plant outfalls. Distribution may further be influenced by the tidal cycle through its impact on manatee movement and foraging. Although the importance of tide on manatee distribution and habitat selection has been acknowledged, it has yet to be studied quantitatively in respect to the manatee population in southeast Florida. The purpose of this study was to examine the effect of the tidal cycle on manatee occurrence at the Florida Power & Light (FPL) Port Everglades Power Plant. Walking surveys were conducted in Port Everglades during manatee season, November 15 – March 31, between 2004 and 2008. During the surveys, the number of manatees in four established locations was noted and the animals categorized based on size as either calf, juvenile, or adult. Water temperature data were also collected at four permanent sample locations. Because many surveys yielded zero manatees observed, data were analyzed using the zero-inflated negative binomial model. Although the manatees at the Port Everglades Power Plant must forage away from the warm-water refuge, my findings show no correlation between tidal state and total manatee occurrence at the FPL Port Everglades Power Plant. The results do, however, suggest that the probability of observing a cow/calf pair is greater during high tide when compared to low and mid-tides (P < 0.05). Total manatee occurrence and the presence of cow/calf pairs were both significantly correlated with water temperature (P < 0.05).

Florida manatees (Trichechus manatus latirostris) seek out warmer waters during winter months when ambient water temperatures drop below 20 degrees Celsius. Over time, manatees have discovered artificial warm water sites from power plant discharges in addition to natural sites such as springs and passive thermal refugia (PTRs). The Florida Power and Light (FPL) Port Everglades power plant in Broward County is one such artificial warm water refuge used by manatees. This plant was shutdown on July 16, 2013, and is expected to remain off line for at least three years during demolition and construction of a new facility. The purpose of this study was to determine changes in habitat usage and other responses to the disruption of a warm water refugia (the closure of a power plant) on Florida manatees within the greater Port Everglades region. From November 15, 2013 to March 31, 2014, manatees were counted at the site via shore line and aerial surveys. Environmental data were collected to determine variables correlated to manatee presence and absense. Two manatees were radio-tagged using remote sensing devices in an effort to identify alternative warm water refugia and feeding areas. Data were collected from state and local organizations and photo-identified manatees were used to analyze for trends in cold stress syndrome (CSS) lesions and watercraft scarring. Results confirmed that manatee presence was positively correlated with heater outlet temperature. Differences did not exist between the results of survey methods between the FPL Port Everglades (PE) and Fort Lauderdale (FL) power plant sites, however, differrences in the aerial survey counts showed an increased presence at the FL site during the colder month of January 2014. Data from tagging identified one manatee that preferred the FL site while another preferred PE, presumably due to more convenient access to feeding grounds in Biscayne Bay. Data from mortality events indicated a low number of CSS and watercraft deaths in Broward County as compared to other parts of the state of Florida. Further monitoring of the study area for the remainder of the shutdown period is recommended, as are improvements in survey design, expansion to include additional environmental data from FL, continued mortality statistic analysis and locating possible PTRs.

Mercury (Hg) is a global contaminant of ecosystems and human health risk, with complicated biogeochemical processes. Mercury sulfide (HgS) dissolution has been suggested as a key process in Hg cycling, as it could potentially increase the pool of inorganic Hg (iHg) for the production of methylmercury (MeHg). Despite previous sporadic observations of enhanced HgS dissolution under certain conditions, much remains unclear on mechanisms of HgS dissolution. The objective of my research was to advance the mechanistic understanding of HgS dissolution, concerning re-adsorption of released Hg, effects of thiol-ligands, and Hg speciation. Considering the lack of feasible techniques to differentiate dissolution and re-adsorption processes, I first developed an efficient method using isotope tracer and isotope dilution techniques to investigate the re-adsorption of released Hg during HgS dissolution. The HgS dissolution rate with consideration of re-adsorption was two times the rate calculated from detecting Hg alone in the presence of O2, indicating the importance of Hg re-adsorption during HgS dissolution. I further examined the role of Hg-ligand complexation in HgS dissolution and Hg(II) re-adsorption using a thermodynamic adsorption method, selecting L-cysteine (Cys) as a model compound for low molecular weight ligands and Waskish fulvic acid (FA) for natural dissolved organic matter (DOM). My results suggest that the presence of Cys enhanced HgS dissolution through the decreased re-adsorption of Hg-Cys complex, whereas Waskish FA inhibited HgS dissolution, possibly because of the adsorption of FA on HgS surface that covered dissolution sites. I further employed a geochemical modeling method to study Hg speciation and the relation of iHg speciation to MeHg, aiming to provide a methodological example for potentially evaluating the implications of Hg species distribution during HgS dissolution on MeHg production. I applied geochemical model PHREEQC to the Florida Everglades, a well-studied wetland with model input parameters available, to determine the distribution of iHg in surface water at different sites. The modeling results suggest that sulfide and DOM govern iHg speciation, and the Hg-sulfide and Hg-DOM species are related to MeHg in environmental media but not fish, suggesting the importance of iHg speciation in MeHg production and the complexity of Hg bioaccumulation.

The South Florida Everglades is a unique ecosystem. Intensive water management in the system has facilitated agricultural, urban, and economic development. The Everglades offers a variety of ecosystem services (ES) to the people living in this region. Nevertheless, the ecosystem is under imminent threat of climate change, which would alter the way water is managed today and ultimately affect the ES offered by the system. On the other hand, substantial restoration is underway that aims to restore the Everglades closer to its historic condition. This research tried to map the public’s preference for Everglades restoration. Using a geocoded discrete-choice survey dataset, the study showed variation in the public’s preference by changing the levels of ES. Additionally, the general public’s attitude toward climate change risk to the Everglades and preference for mitigation were also assessed using the survey data.