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Production and Modification of Biochar for Organics Removal and Soil Ammendment / Production and Modification of Biochar for Organics Removal and Soil AmendmentUnknown Date (has links)
The use of biochar as a soil amendment for agricultural purposes in various cultures has been around for centuries, perhaps millennia. This study seeks to advance this practice by investigating the use of engineered biochar, by chemical impregnation, as a means of optimizing the nutrient retaining properties of soil. As a potentially major source of nutrients are found in wastewater, the biochar is also checked for its viability of pre-loading said char with nutrients, by first using it as a means to clean wastewater. First biochar (BC) is used to produce activated carbon (AC) and comparisons are made between the BC and AC in their ability to remove organics from wastewater, then the biochar is chemically modified with three chemicals, Ferrous sulfate Heptahydrate (Copperas), Calcium Chloride (Ice Bite), and Aluminum Potassium Sulfate Dodecahydrate (Alum), and tested for nutrient (orthophosphate and nitrate) sorption. The biochar failed in its unaltered form of removing organics (COD) from wastewater, actually adding COD into the solution. Only when the char was turned into activated carbon did it express the ability to remove COD. The chemically modified chars showed promise in their ability to adsorb nutrients (phosphate and nitrate) from solution (wastewater), as well as enhance the retention of said nutrients (particularly phosphate) within a sandy soil. The biochar amendments also significantly increased the water holding capacity of the sandy soil, regardless of BC type, by no less than 10%. / A Thesis submitted to the Department of Civil and Environmental Engineering in partial fulfillment of the requirements for the degree of Master of Science. / Summer Semester 2018. / July 12, 2018. / Includes bibliographical references. / Hafiz Ahmad, Professor Directing Thesis; Gang Chen, Committee Member; Youneng Tang, Committee Member.
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Biological Reduction of Selenate and Recovery of Elemental Selenium from Wastewater in a Continuous-Flow SystemUnknown Date (has links)
The biological degradation of selenate to elemental selenium and recovery of valuable selenium nanoparticles has been extensively studied
and reported by researchers throughout literature. The major challenges in degradation and recovery processes are the reduction of high
concentration of selenium oxyanions and effective separation of bacterial cells and sludge from these economically beneficial elemental selenium
nanoparticles. This study seeks to investigate the efficacy of a novel combination system comprising a biological reactor, a separating chamber
and a tangential-flow ultrafiltration module (TFU). The biological reactor was investigated for its ability to reduce selenate at high loading
rates. The separating chamber containing the inclined bacterium-nanoparticle separator was investigated for its ability to separate bacteria
from nanoparticles. The TFU was investigated for its ability to induce a water-bacterium-nanoparticles separation even at high selenate loading
rates. The reactor system worked in synergism to remove high concentration of selenate from wastewater and simultaneously recover the valuable
elemental selenium nanoparticles thereby eliminating the additional use of chemicals or post-treatment operations. / A Thesis submitted to the Department of Civil and Environmental Engineering in partial fulfillment of the
requirements for the degree of Master of Science. / Fall Semester 2018. / November 26, 2018. / Includes bibliographical references. / Youneng Tang, Professor Directing Thesis; Gang Chen, Committee Member; Clayton Clark, Committee
Member.
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EFFECTS OF LOW PH WATER ON THE ADENINE NUCLEOTIDE POOL AND LOCOMOTOR ACTIVITY OF THE GULF KILLIFISH, FUNDULUS GRANDISUnknown Date (has links)
The effects of water acidification on the composition of the adenine nucleotide pool and locomotor behavior of the estuarine teleost Fundulus grandis were investigated. Fish exposed for up to 96 hours to reduced pH exhibited highly significant declines in ATP concentration, total adenylate concentration, and adenylate energy charge, i.e., / (ATP) + 1/2(ADP)(' ) / (AMP) + (ADP) + (ATP)(, ) / in brain, liver, and gill tissues. Muscle energy charge and ATP also decreased concurrent with increased ADP concentration, and particularly AMP concentration. Therefore, the total adenylate concentration was only slightly reduced. Exposure to pH 4.0 and 5.0 media produced the greatest declines in these parameters. Less pronounced declines were observed in fish exposed to pH 6.5 water. The greatest changes occurred within the first 24 to 48 hours of acidification but statistical analysis indicated that the hydrogen ion concentration was more important in altering adenylate metabolism than the length of exposure. / Low pH water induced changes in the daily locomotor activity pattern of F. grandis, particularly at pH 5.0 and 4.0. Box-Jenkins time series analysis was applied to the behavioral bioassay, permitting quantitative assessment of activity rhythm changes resulting from exposure to acidity. Activity data were obtained using an infrared photoelectric detection system. Results of time series model identification and estimation programs indicated a progressive decline in the daily rhythmicity of locomotor activity as the degree of acidification increased. Fish generally displayed hyperactive responses to low pH water with increased activity during the normally inactive diurnal periods. Under these conditions, extensive mucification, altered body coloration, difficulties in orientation and buoyancy control, and a cessation of feeding also occurred. The results of these studies suggest that environmental pH levels below 6.5 may critically impair energy metabolism and behavioral functions of fishes. / Source: Dissertation Abstracts International, Volume: 41-03, Section: B, page: 0874. / Thesis (Ph.D.)--The Florida State University, 1980.
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CHARACTERIZATION OF THE STRUCTURE OF MARINE AND ESTUARINE BENTHIC AND FOULING MICROBIAL COMMUNITIES USING LIPID CHEMISTRYUnknown Date (has links)
The estuarine benthic and fouling communities form essential elements in the trophodynamics of detrital and benthic ecosystems, the mediation of mineral recycling, and initial colonization of submerged surfaces. Changes in the structure of these vital communities have traditionally proved labo / Source: Dissertation Abstracts International, Volume: 41-11, Section: B, page: 4053. / Thesis (Ph.D.)--The Florida State University, 1980.
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On the observational and numerical aspects of explosive East coast cyclogenesisUnknown Date (has links)
An explosively deepening storm or 'bomb' (hereafter quotes omitted) is defined by Sanders and Gyakum (1980) as an extratropical cyclone whose central mean sea-level pressure falls at least 1 mb per hour for 24 hours. The composites constructed from the daily global analyses generated and archived at the European Center for Medium Range Weather Forecasts (ECMWF) accurately describe the three-dimensional kinematic and thermodynamic structure of bombs over the entire depth of the troposphere. Furthermore, a regional $-\overline{\omega\sp\prime\alpha\sp\prime}$ covariance is used for describing the intensity of baroclinic instability and hence cyclogenesis. / Numerical experimentation of explosive east coast cyclogenesis is performed using the Florida State University Global Spectral Model (FSUGSM). The three cases examined here are the Presidents' Day storm of 18-19 February 1979 and the North Atlantic and Pacific bombs of 18-20 January 1979 which formed off the east coasts of the United States and Japan respectively. The use of a global model provides a framework for studying the phenomena on the 3-5 day time scale and for examining the sensitivity of the forecasts to data analysis in regions several thousand km upstream of the storm domain. A technique is developed to uniquely partition and quantify the role of the dynamical and physical processes in the explosive cyclogenetic process. Additionally, the complete model-generated four-dimensional data sets are used to compute residual-free Eulerian vorticity budgets. / The results of this work reveal that explosive cyclogenesis is a baroclinic phenomena in which the rapid intensification in the presence of pronounced middle and upper tropospheric forcing is enhanced by a highly destabilized lower troposphere that is strongly heated and moistened by upward (positive) oceanic sensible and latent heat fluxes. The focus of the ongoing research is shifting away from the problem of actually predicting explosive cyclogenesis toward improving the skill of bomb forecasts and simultaneously extending the range of predictability of such events. / Source: Dissertation Abstracts International, Volume: 49-10, Section: B, page: 4209. / Major Professor: T. N. Krishnamurti. / Thesis (Ph.D.)--The Florida State University, 1988.
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VARIATIONAL INITIALIZATION OF ATMOSPHERIC FIELDS--A QUASI-GEOSTROPHIC DIAGNOSTIC MODELUnknown Date (has links)
Source: Dissertation Abstracts International, Volume: 32-12, Section: B, page: 7096. / Thesis (Ph.D.)--The Florida State University, 1972.
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Optimization of Groundwater Long-Term Monitoring Network Optimization of Groundwater Long-Term Monitoring Network with Ant Colony Optimization with Ant Colony OptimizationUnknown Date (has links)
Groundwater remediation is conducted in polluted sites to remove contaminants and to restore ground water quality. After remediation
goals are achieved, long-term groundwater monitoring (LTM) that can span decades is required to assess the concentration of residual
contaminants and to avoid the risk of human health and environment. On large remediation sites, the cost for maintaining a LTM network,
collecting samples, conducting water quality lab analysis can be a significant, persistent and growing financial burden for the private
entities and government agencies who are responsible for environmental remediation projects. LTM network optimization offers an opportunity
to improve the cost-effectiveness of the LTM effort while meeting data accuracy requirements. The optimization includes identifying the
redundancy in the monitoring network, and recommending changes to protect against potential impacts to the public and the environment. This
study develops a variant ant colony optimization (VACO) method, using ordinary kriging (OK) or inverse distance weighting (IDW) for data
interpolation, to identify optimal LTM networks that minimize the cost of LTM by reducing the number of monitoring locations with minimum
overall data loss. ACO is a global stochastic search method inspired by the collective problem-solving ability of a colony of ants as they
search for the most efficient routes from their nests to food sources. The performance of ACO variant (VACO) developed in this study is
evaluated separately in two test cases. In the first case, VACO is used to solve a simplified traveling sales person problem. In the second
case, both enumeration method and VACO are employed for optimization of a synthetic long term monitoring network of 73 wells generated from a
groundwater transport simulation model. The two sets of test show that the VACO performs well for optimization problems. The VACO is finally
adopted for the optimization of a long term monitoring network of 30 wells in Logistic Center, Washington, with the data interpolation
methods of inverse distance weighing, ordinary kriging, and modified inverse distance weighing which is developed in this study. The
optimization results are analyzed and group of ideal redundant wells identified. The conclusion of this study is summarized at the end, and
future work is suggested. / A Dissertation submitted to the Department of Civil and Environmental Engineering in partial fulfillment of
the requirements for the degree of Doctor of Philosophy. / Fall Semester 2017. / November 17, 2017. / ant cology optimization, convergence, ground water long term monitoring network, iteration, spatial optimization,
swarm intelligence / Includes bibliographical references. / Gang Chen, Professor Co-Directing Dissertation; Ming Ye, Professor Co-Directing Dissertation; Xiaoqiang
Wang, University Representative; Amy Chan Hilton, Committee Member; Wenrui Huang, Committee Member; Youneng Tang, Committee Member.
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Fate of the Mesophotic Coral Ecosystem (MCE) in the Northeastern Gulf of Mexico after the Deepwater Horizon Incident: Impacts, Restoration, Conservation, and HazardsUnknown Date (has links)
The Gulf of Mexico, one of the most geomorphologically complex oceanic basin, is also one of the most prolific hydrocarbon reserves in
the world. It hosts a varied range of marine communities from shallow reefs and estuarine communities in coastal areas, to deep-sea and
chemosynthetic communities in greater depths. In some particular areas in water depth between 50 to 120 m are hosted the mesophotic reef
ecosystem, also known as the twilight communities, where sunlight is almost extinguished but still enough to support some photosynthesis.
Mesophotic ecosystems are mainly characterized by the presence of both light dependent and independent corals, which are the bioengineering
support from a vast variety of invertebrate and vertebrate that compound the mesophotic coral ecosystem. One of these mesophotic coral
ecosystem, the Pinnacle Reef Trend, was under the influence of floating oil after the Deepwater Horizon incident released more than 4.1
million barrels of crude oil and 500 T of gas to the environment. Visible injuries in over 400 octocoral and antipatharian colonies were
quantified in the aftermath of the DWH oil discharge. Observations were made in September 2011 at water depths of about 65 to 75 m in the
Pinnacle Reefs area offshore of Mississippi and Alabama, Gulf of Mexico, using a digital macro camera deployed from an ROV to examine the
coral populations of two principal sites: Alabama Alps Reef (AAR) and Roughtongue Reef (RTR). Observed taxa (identifications provisional),
listed in order of injury frequency, included the following: Hypnogorgia pendula (Duchassaing & Michelotti, 1864), Bebryce spp., Thesea
nivea (Deichmann, 1936), Swiftia exserta (Ellis & Solander, 1786), Antipathes atlantica (Gray, 1857), Stichopathes sp., and Ellisella
barbadensis (Duchassaing & Michelotti, 1864). The most conspicuous injuries observed were a biofilm, often with a clumped or flake-like
appearance, that covered sea-fan branches. Extreme injuries were characterized by bare skeleton, broken, and missing branches. Comparing the
2011 results to previous photo surveys in the same study sites between 1997 and 1999, we found, in 2011, significantly elevated occurrences
of injury covering more than 10% of colony area among taxa with growth forms > 0.5 m. We hypothesize that Tropical Storm Bonnie
facilitated and accelerated the mixing process of dispersant-treated hydrocarbons into the water column, resulting in harmful contact with
coral colonies at mesophotic depths. Analysis of sediment PAH concentrations at AAR and RTR found levels elevated above pre-DWH discharge
values, but orders of magnitude below toxicity thresholds established for fauna in estuarine sediments. The PAH concentrations measured in
octocoral and echinoderm tissue samples from AAR and RTR were low compared to detection thresholds (10 - 100 ppb). Our findings indicate that
coral injuries observed in 2011 resulted from an acute, isolated event rather than ongoing natural processes. Maximum Entropy Modeling was
applied to predict the spatial extent of mesophotic azooxanthellate octocorals and antipatharians within the mesophotic area located between
Mississippi (Pinnacle Trend Area) and the mid continental shelf and upper slope of Florida, eastern Gulf of Mexico. Habitat prediction models
were generated using geo-referenced, coral-presence records obtained by compiling photographic samples with co-located geophysical data,
oceanographic variables, and atmospheric variables. Resulting models were used to predict the extent of suitable habitat in the study area.
An independent set of presence-records was used to test the model performance. Results (general and by taxon) predict that suitable areas for
MCE exceed 400 km2, which occur along carbonate mounds and paleo-shoreline ridges (hard substrata and high ruggedness) with lower amounts of
fine sediments and surrounding waters rich in CDOM and upwelling currents (w). The model results significantly exceeded (>0.5) random
output and predicted that ruggedness and CDOM are the most important variables associated with coral habitat. Areas of hard substrate within
the study area that were not identified as coral habitat by the model suggest that mesophotic sea fans and sea whips depend as much on the
chemical and physical conditions (e.g. currents that transport oxygen and food) as on hard substrata for settlement. Finally, three submarine
channels that incise into the continental slope in Northeastern Gulf of Mexico have been identified and described. The slope-source channels,
seemingly formed after a mass wasting events, are 65 km long and 2.5 km width on average. They show a transition of their transversal profile
from V-shape in the head to U-shape in the toe, high sinuosity in the upper ¾ of the channel, showing accumulation of sediments in the
turn-sections of the channels, and accumulation of sediment on the walls due to collapsing of unconsolidated sediments. Sedimentary facies
obtained by sediment cores show the evidence of disturbed interval of sedimentation and erosion, with erratic periods of laminar
sedimentation, erosion, turbidities, disturbed by coarse fractions of sediment. C14 dating of sediments cores from the inside of the channel
suggest that hydrodynamic erosion is continuously occurring inside the channel, exposing older sediments to the surface. However, we do not
discard the possibility that mass wasting processes are still occurring in the area. The presence of coarse sediment fractions typically
found in the continental shelf, beside the occurrence of turbidite homogenous fractions demonstrate that sediment wasting from the upper
slope could be still occur. This could lead to a potential disaster in the area because of the presence of oil industry structures. Massive
turbidity flows and submarine slumps have been described to occur in this area and other places / A Dissertation submitted to the Department of Earth, Ocean, and Atmospheric Science in partial fulfillment
of the requirements for the degree of Doctor of Philosophy. / Fall Semester 2017. / November 17, 2017. / coral, DWH, Environmental modeling, Geomorphology, mesophotic, Oil and gas / Includes bibliographical references. / Ian R. MacDonald, Professor Directing Dissertation; Janie L. Wulff, University Representative; Markus
Huettel, Committee Member; Amy Baco-Taylor, Committee Member; Mariana Fuentes, Committee Member.
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Shifting Inputs and Transformations of Nitrogen in Forested and Mixed Land Use Basins| Implications for Hydrologic Nitrogen LossSabo, Robert Daniel 23 February 2019 (has links)
<p> Increased N inputs along with changes in population, land use, and climate have globally altered the N cycle. This alteration has been associated with increased food, energy, and fiber availability, but has also contributed to the degradation of human health conditions and diminishment of expected ecosystem services in many regions throughout the world. In this context, my research explored the impact of shifting anthropogenic N inputs and other environmental drivers on terrestrial N surpluses and linked changes in terrestrial surpluses to observed changes in N loss to aquatic systems. Working in both forested and mixed land use catchments in the eastern USA, I hypothesized that processes that reduced terrestrial N surpluses in catchments by 1) reducing N inputs, 2) increasing plant uptake, and/or 3) increasing gaseous efflux would result in decreased hydrologic N export. Identification of potential processes was accomplished by first generating long-term atmospheric, remote sensing, terrestrial, and hydrologic datasets for individual catchments. The first two components of my dissertation highlighted potential interactions between atmospheric N deposition, acidic deposition, climate, and disturbance in influencing terrestrial N availability, as indicated by N isotopes in tree rings, in forested catchments. Leveraging trend analysis and statistical models, I identified continued long-term declines in terrestrial N availability in forests, but this decline was likely being modified by disturbance and long-term reductions in acidic deposition. The final component of my dissertation involved developing a lumped conceptual model to explain water quality trends in three mixed land use catchments within the Chesapeake Bay watershed. This study assessed the relative influence of point source N loading, agricultural practices, and atmospheric N deposition on long-term trends in riverine N loss. Insights from the simple N loading model strongly suggested that declines in atmospheric N deposition and point source loading were key drivers of historical water quality improvement. Whether relying on quasi-mass balances or dendroisotopic records, findings from this research emphasize the usefulness of constructing proxy datasets of terrestrial N surpluses in identifying likely processes driving changes in hydrologic N loss in forested and mixed land use catchments.</p><p>
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Developing Spawning Protocols and Embryological Benchmarks for a Tropical Marine Fish (Albula spp.) in CaptivityHalstead, William Robert, III 23 February 2019 (has links)
<p> Relying on field research to complete the life history for certain fish species can be inadequate, but laboratory research can be used to fill these gaps. These gaps exist for Bonefish (<i>Albula</i> spp.), a tropical marine fish and popular sportfish. In this study, aquaculture techniques were applied to Bonefish in a captive setting at Harbor Branch Oceanographic Institute (HBOI) and Cape Eleuthera Institute (CEI) to induce spawning and describe early ontogeny. Photothermal manipulations and hormone injections were used to induce gonad maturation and spawning, which was achieved once at CEI and is the first record of hormone-induced spawning for Bonefish. From that spawn, egg and larval development were recorded and described through 26 hours and 56 hours respectively, representing the first record of these early life stages for Bonefish. This work expands upon what is known about Bonefish reproductive biology and will be useful for management and future captive research.</p><p>
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