Source: Dissertation Abstracts International, Volume: 32-12, Section: B, page: 7096. / Thesis (Ph.D.)--The Florida State University, 1972.

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.

Fast moving hurricanes and stationary nor’easters have resulted in significant flood damage in Chesapeake tidewater communities. The Chesapeake Bay region is one of A m erica’s most vulnerable regions with respect to sea-level rise, which will only increase storm surge impacts over upcoming decades. While the general trends are well documented, there is limited information relevant to specific communities’ relative flood risk and response. The dearth o f data is especially troublesome given the lengthy period o f time generally needed for communities to plan and implement adaptive action. This study contributes to the regional understanding of flood and sea-level rise vulnerability by applying physical, social, and combined vulnerability indices to tidally influenced localities along the Chesapeake Bay. Unlike other combinations of physical and socioeconomic data, the physical vulnerability index for this study is calculated at a scale that can directly link into social vulnerability index information at local and regional levels. The research also considers the distribution of coastal natural capital (in the form o f marshes and forests) alongside these indices at comparable scales. By calculating the indices for conditions o f the early 2000s, this study also tested their predictive value against Hurricane Isabel, a landmark 2003 storm that flooded areas across the region. Systematic verification “hindcasts” o f past events are relatively rare for vulnerability index evaluation. By attempting to establish connections between real flooding data, socioeconomic activity, and vulnerability indices, this study questions whether theoretical vulnerability indices work as true proxies for real world conditions. The results question the true utility o f these indices by showing limited relationships between vulnerability and changes in community socio-economic activity. The research also emphasizes the need for more data collection and consideration in order to better comprehensively understand coastal flood impacts and their management implications.

As created wetlands are becoming more common due to compensatory mitigation under section 404 of the Clean Water Act, it has become important to understand how the vegetation community and the soil nutrient availability develop over time. For a created wetland to replace the function of the destroyed natural wetland, the biogeochemical cycling and vegetation community must replicate the natural system. In this study, I sampled the vegetation community as well as the soil and porewater nutrient availability in four created wetlands in southeastern Virginia, constructed and managed by the Virginia Department of Transportation. All the sites used in this study had areas of dense Typha spp. stands, which had been identified as problem areas by the site managers,based on inferences from previous research indicating Typha are invasive in other types of wetlands. In many of these sites, the Typha populations were removed by cutting and herbicide spraying, due to the assumption that the dense Typha stands hinder the biodiversity and therefore reduce the functionality of the created wetlands. As part of this study, I sampled the composition of the vegetation community both within Typha stands and in areas dominated by other species. I was able to show that the dense Typha stands do not lower the species richness or the Shannon diversity index of the vegetation community. I also measured the nutrient availability associated with Typha stands and areas dominated by other vegetation and found no consistent significant differences in soil nutrient availability. However, I did observe a change in nutrient concentration across all vegetation communities and in all study sites from 2006 to 2007. The soil a range of 20 and 55 in 2007. These results may indicate that as created wetlands mature the amount of soil total phosphorus (TP) decreases and the amount of total nitrogen (TN) increases, resulting in a steady state of P limitation relative to N as the site matures. Since these conclusions are based on only two years of data, longer-term research is needed in created wetlands to verify trends in soil TP and TN dynamics as these sites mature.

This project attempts to identify toxic organic substances used in Virginia, which cannot be detected by conventional analytical procedures. A list from the Virginia Bureau of Toxic Substances Information which contained substances reported as used in manufacture or produced in Virginia was cross-referenced with the Master File of toxic substances compiled pursuant to the Toxic Substances Control Act. Organic chemicals appearing on both lists were thus identified as toxic substances used in Virginia, and were the subjects of this research. Due to the reporting requirements of the Virginia Toxic Substances Information Act, the 113 "compounds" do not include substances used solely in repair work in Virginia. In addition, since chemicals used only as pesticides or drugs were not included in the Master File, these types of substances do not appear in the list of 113 "compounds". Conventional organic analytical procedures were studied, and five basic critical parameters which could impair analysis were determined: volatility, stability, solubility, adsorption in liquid chromatography, and problems in GC and GC/MS. The literature was then researched for these critical parameters to indicate the ability of conventional techniques to detect the 113 "compounds". "Compounds" which were either not detectable or possibly detectable by conventional techniques were assessed for potential long term environmental accumulation. An analytical technique, involving a minimum of steps, was then developed to analyze specifically for those "compounds" requiring special monitoring.

Kraft pulp and paper mill effluents (KPPME) collected on three occasions were analyzed for resin acids, aliphatic hydrocarbons, and aromatic hydrocarbons. The maximum total concentrations of these compounds found in secondary effluents were 8 mg/L resin acids, 4.0 mg/L resolved aliphatic hydrocarbons, and 0.2 mg/L resolved aromatic hydrocarbons. Abietic acid and dehydroabietic acid were the two major components in resin acid fractions and were responsible for > 70% of the total concentration. Analyses of estuarine water and sediments collected from the outfall and nearby areas showed that dehydroabietic acid was the major resin acid in either water or sediment. Concentrations of dehydroabietic acid ranging from 0.4 (mu)g/L to 3.6 (mu)g/L were found in water samples collected during high water slack and up to 5.8 (mu)g/g dry sediment were found in sediments. This indicates that dehydroabietic acid is persistent in the estuarine environment. Most of the resin acids identified in the KPPME were present in sediments taken near the outfall. Concentration-station profiles of the major resin acids showed maximum concentrations near the outfall which indicates that the KPPME is a major source for these acids. The concentration-depth profiles of the resin acids in core samples appear to reflect the major events occurring in the mill. If this is true, average sedimentation rates after 1973 are estimated to be 2-3 cm/year near the outfall and 1 cm/year in the nearby areas. Sediment hydrocarbon concentrations also peaked near the outfall area. Discharge of the KPPME and the use of fuel oil in the mill are among the contributors of petroleum hydrocarbons in the sediments. Cordgrass (Spartina cynosuroides) in the adjacent marsh areas is likely to be the major source for high MW n-alkanes to the sediments. Retene was identified in the sediments. The concentration-station and concentration-depth profiles of retene in river sediments, however, suggests that it is unlikely to be derived primarily from resin acids near the discharged area. Retene was found to be predominant in one sample taken from the marsh area in March 1981, but it was a minor component in the sample taken in November 1982. Further study is needed to understand production process of this compound.

Bioretention systems are commonly used to treat and detain stormwater runoff and help mitigate for many negative effects of urbanization. Despite the widespread use of bioretention systems, few field-based studies have assessed how these facilities affect water quality many years after installation. The goal of this project is to assess the pollution reduction effectiveness of lined bioretention facilities that have been in use and functioning for 4-8 years. To meet this objective, this project measured water quality characteristics of stormwater flowing into and out of seven facilities installed throughout Portland, Oregon during real storm events. Stormwater grab samples were taken over a 2-year period during the fall, winter, and spring. Results showed decreased concentrations of total suspended solids (TSS; 94%), ammonia (85%), total copper (59%), total zinc (80%), and dissolved zinc (41%). Results for dissolved copper indicated an overall increase in outflow concentrations of 23%, however variability between facilities was high. These results support other similar findings showing that TSS is effectively reduced by bioretention facilities, even after 4-8 years of use. However, based on this study, effective TSS removal by bioretention facilities does not necessarily equate to equally effective treatment of other pollutants, especially orthophosphate and nitrate, which increased in outflow from the bioretention facilities by 141% and 2070%, respectively. Results of this study indicate that additional research is necessary to determine the significance of the observed increase in nutrients, understand the underlying mechanisms, and test possible design modifications to improve nitrate and orthophosphate removal.

Avian communities, because of their potential high diversity, are ideal for studying the response to potential quantity of resources provided by local and regional habitat. Urban neighborhoods vary in types and magnitudes of anthropogenic stressors they experience, resulting in a continuum of anthropogenic disturbance, often referred to as a gradient of urbanization. The aim of this study was to investigate anthropogenic drivers of urban bird communities in three Portland, OR neighborhoods (Hillsdale, Lents, and Pearl). The three major questions of this study were: 1) What are the significant landscape traits that characterize the neighborhoods? 2) Is there evidence that the urban matrix may host similar avian community assemblages as neighborhood green space? And 3) Are landscape characteristics able to predict native bird communities, and if so, what scale is most explanatory? Neighborhoods were sampled for three months (May - July, 2018) during the breeding season of local birds. Utilizing a community-based approach, parks (n = 17) and neighborhood residential areas (n = 34) were sampled using 50-meter point counts. Community attributes (richness, abundance, and diversity) were compared to landcover (percent canopy, herbaceous and grass, and impervious surface cover), anthropogenic factors (population density and building density), and front-yard vegetative characteristics. Neighborhoods differed in degree of urbanization, with Hilldale being the least urbanized, Lents intermediate, and Pearl the most urbanized. My study found that Portland's urban and suburban avian communities are dominated by relatively few species (13 account for ~98% of observations). Differences between native avian community attributes were detected by neighborhood but avian communities did not respond strongly to gradient analysis or regression modeling with landcover characteristics. Within neighborhoods, habitat patches had differing levels of native bird diversity. Recreational parks, on average, tended to have lowest bird diversity when compared to residential sites and nature parks. Though few species were represented, avian guilds responded to urban gradients within neighborhoods. Foliage gleaners and insectivores were seen to decrease with increasing urbanization, whereas omnivorous birds increased. This shift in avian guild abundance indicates that species with more specialized traits did less well in more urban areas when compared to generalist species such as omnivores.

This study provides a detailed survey of the presence, concentration levels, and spatial distribution of organic and inorganic contaminants in sediment and tissue samples collected within Everglades and Biscayne National Parks. The results of these analyses revealed elevated concentrations of arsenic, and lead and chromium in Everglades National Park (ENP) sediments exceeding Potential Effects Levels (PEL) in 9, 5 and 5% of sediment samples and concentrations of nickel exceeding Threshold Effects Levels (TEL) in 5% of samples. In Biscayne National Park, arsenic exceeded TEL in 4400 of sediment samples. Organic analyses of ENP sediments revealed elevated concentrations of DDT and its metabolites in 5% of the samples. Fish tissue analysis indicate that Endosulfan may pose a hazard in aquatic environments due to its high frequency of detection, Endosulfan sulfate in 85% and β-Endosulfan in 5% of samples.

The land application of biosolids to provide nutrients and organic matter is widely practiced in agricultural applications. However, the potential benefit of applying biosolids to disturbed rangelands has not been adequately evaluated. Thus the main goal of the current study was to evaluate the potential economic and environmental benefits of applying biosolids to disturbed rangeland with the main focus on evaluating the impact on forage quality and quantity as a function of biosolids type and application rate. Three types of biosolids (aerobically, anaerobically, and lime stabilized biosolids) were surface applied with no subsequent tilling at various loading rates (1, 5, 10, and 20 times nitrogen plant requirement) in Skull Valley, Utah. It was demonstrated that forage quality (crude protein and in vitro digestibility) and quantity (biomass) can be improved by biosolids land application. Also, the analyses of the soil and forage for 16 specific metals indicated no measurable accumulation except for a statistical increase of sodium compared with the control. No negative impact on soil moisture infiltration (e.g., drainage) properties were seen. The economic analysis of biosolids land application on disturbed rangeland associated with improvements in forage quality indicated that use of biosolids for land restoration would be profitable. The highest potential financial return was observed when anaerobically digested biosolids were land applied at 20 times the agronomic rate. Finally, despite the numerous benefits associated with biosolids land application, there remain a number of human health and environmental concerns regarding its use on publicly accessible lands that should be addressed in future studies. These concerns are primarily associated with the accumulation of heavy metals and recalcitrant organics (e.g. polychlorinated biphenyls, dioxins, brominated biphenyls, and pharmaceuticals and personal care products) that may be associated with the biosolids.