This study aimed to understand the ecology of the threatened, habitat-forming seagrass, Zostera capensis in Langebaan Lagoon, a marine protected area that forms part of the West Coast national park, South Africa; and the physiological strategies that allow this habitat to persist in sub- and supra-optimal temperatures. First, the environmental drivers responsible for spatial and temporal variability in Zostera and its associated macro-epifauna were determined. Secondly, the effects of temperature and the role of algal grazing in maintaining seagrass performance under temperature stress were investigated. Seasonal field collections of seagrasses and their associated macro-epifauna were undertaken, along with regular measurements of key environmental variables. Thereafter, mesocosm experiments were performed to measure the responses of Zostera to thermal stress and grazing using morphometry, fluorometry, chromatography and biochemistry. Significant seasonal variability in seagrass distributions with severe diebacks in summer were found, which influenced associated macro-epifauna communities. Populations responded to environmental stress by changing their growth form producing small-leaves in high densities in the high intertidal, while those in low intertidal and subtidal areas produced sparse, large-leaved populations. These distinct populations supported unique faunal diversities, which were dominated by grazing invertebrates. Temperature was a consistent driver of seagrass density and leaf size, while turbidity and exposure were key environmental factors that influenced macro-epifaunal patterns. Macro-epifaunal abundances were highly positively correlated with seagrass leaf width and biomass. Different growth forms displayed different responses to thermal stress, including a higher photosynthetic rate, and accumulations of carbon and nitrogen as phenolic compounds, in small- compared to large-leaved plants. This implies that large-leaved populations are more vulnerable to stress from fouling, which was evident in their larger epiphyte loads, compared to small-leaved populations. In addition, grazers were ineffectual at regulating epiphyte growth which increased under warming conditions. These findings suggest differences in resilience between sub-populations of Zostera, and attest to their capacity to recover from environmental stress. They further emphasise the significance of identifying characteristics and acclimation strategies that allow habitats to persist under climate change, and thus sustain biodiversity and productivity, as well as continue to provide important ecosystem services.

Duckweed species L. turionifera and W. borealis grow on Wellsville Municipal Sewage Lagoons in northern Utah and, when harvested, contribute to the removal of phosphorus and pharmaceuticals from wastewater. Microcosm studies showed that duckweed contains an average of 1% phosphorus (dry weight) and removes 113 mg-P/m2day under 200 μmol/m2sec light. Duckweed in laboratory experiments reduced influent phosphorus ranging from 3.88 to 5.2 mg-TP/L to effluent concentrations of 0.88 mg-P/L in 3 days to 0.16 mg-P/L (0.32 mg-TP/L) with continual harvesting and a liquid retention time of 46 days. Duckweed removal of pharmaceuticals was comparable to removal by membrane bio-reactors. Duckweed removed 99% acetaminophen mainly by plant uptake; 98% progesterone primarily by absorption to plant tissue; 90% fluoxetine by adsorption with some biological removal attributed to plants; and sulfamethoxazole removal varied between 25 to 90% depending on polarity. Carbamazepine did not react with duckweed. Typical influent wastewater concentrations of the five pharmaceuticals in this study were not toxic to duckweed with an EC50 value of 614 μg/L per compound. HPLC/MS detection of pharmaceuticals in liquid samples using solid phase extraction at a neutral pH and silanized glassware produced 92-102% recoveries. Analysis of extracted solids produced lower recoveries. Solid extraction efficiencies ranged from 56-70% for samples stored for 24 hours and decreased with increasing storage time. Field growth studies showed higher than expected duckweed growth rates in the spring compared to three models due to turion germination after the ice melts. The growth rates decreased in the fall due to turion formation in preparation for winter. Harvesting duckweed from the Wellsville Municipal Sewage Lagoons should begin after full surface coverage around June 17th and end when temperatures fall below 15 °C around September 15th. Bi-weekly harvests with a starting plant density of 75 g-dry duckweed/m2 for the lagoons operating at 0.547 MGD and 5 mg-TP/L are required to physically remove enough phosphorus in order to meet the city’s 432 kg-P/yr discharge permit. A duckweed phosphorus harvesting system in Wellsville was estimated to produce enough biomass to meet the P-discharge limit until the flow increases above 0.656 MGD around the Year 2017.

The world has never been more connected than it is today. While this is true for people, it is also true for Earth's flora and fauna. Unfortunately, this connectedness has contributed to unprecedented invasive species introductions around the world. Most introductions result in an introduced species dying out in the newly invaded territory and never becoming established. Other introduced species establish and persist for years, but never have a noticeable effect on local ecosystems. However, occasionally, an invasive species gets introduced to a new area and has negative impacts on native plant and animal life. The Indo-Pacific swimming crab, Charybdis hellerii, was introduced to the southern Indian River Lagoon (IRL) in the 1990s. Recently, it has been reported to be expanding its non-native range northward up the IRL and into more northerly east coast states. To better understand the ecological role C. hellerii fills in the lagoon and the threat it poses to the economically important and native Callinectes sapidus, this study utilized stable isotope analysis to assess dietary overlap and competition between these species. The results of this study indicate significant overlap in dietary resource usage suggesting C. hellerii is likely feeding on some of the same prey items and competing with native C. sapidus. Based on the increasing numbers of C. hellerii and their reported range expansion, they appear to be establishing populations in the U.S. and will continue to compete with C. sapidus. This could negatively impact C. sapidus populations in the IRL, which is bad for the crab, bad for the fishery, and bad for the lagoon. Further, competition in the IRL is concerning for the rest of the southeastern U.S. states that appear to be in the early stages of a C. hellerii invasion. The findings of this study illuminate the need for further research into the ecological niche C. hellerii is filling in the IRL and the interactions it is having with, as well as the effects it is having on, native species in the lagoon. This study and future research will allow fisheries managers to devise more effective strategies to limit the spread of C. hellerii and minimize the harm it can do in non-native environments.

No description available.

This research uses Bayesian analysis of fluorescence spectroscopy results to determine if wastewater from the Heber Valley Special Service District (HVSSD) lagoons in Midway, UT has seeped into the adjacent Provo River. This flow cannot be directly measured, but it is possible to use fluorescence spectroscopy to determine if there is seepage into the river.Fluorescence spectroscopy results of water samples obtained from HVSSD lagoons and from upstream and downstream in the Provo River were used to conduct this statistical analysis. The fluorescence 'fingerprints' for the upstream and lagoon samples were used to deconvolute the two sources in a downstream sample in a manner similar to the tools and methods discussed in the literature and used for source apportionment of air pollutants. The Bayesian statistical method employed presents a novel way of conducting source apportionment and identifying the existence of pollution.This research demonstrates that coupling fluorescence spectroscopy with Bayesian statistical methods allows researchers to determine the degree to which a water source has been contaminated by a pollution source. This research has applications in determining the affect sanitary wastewater lagoons and other lagoons have on an adjacent river due to groundwater seepage. The method used can be applied in scenarios where direct collection of hydrogeologic data is not possible. This research demonstrates that the Bayesian chemical mass balance model presented is a viable method of performing source apportionment.

The Sultanate of Oman is a rapidly modernizing country with a significant length of its coastline slated for development. Much of the coastline is still in its natural state and basic studies describing the sedimentary systems need to be conducted in order to plan effectively for their sustainable development and to monitor changes in them with time. For such purposes, sediment samples (surface and sub-surface), elevation data, and serial sediment cores were collected at Sur Lagoon during three field seasons. The research objectives, procedures, results, and analyses for Sur lagoon are presented in three chapters. The first chapter compares textural facies, identified on the basis of particle-size distribution (PSD) of surface sediments from Sur Lagoon and evaluated using multi-variate cluster analysis, for their value in recognizing modem sedimentary environments. Clustering the full PSD size spectrum (0.0375- 1888 μm) shows that facies identification is possible is closely tied to surface elevation, particle-size decreasing with increasing elevation above mean sea level. This analytical technique should be tested under different conditions to assess further its utility. The second chapter discusses the taphonomically distinct and laterally extensive (> 1 km2) bivalve shell bed deposited by a tsunami on November 28th, 1945. Taphonomic characteristics of this unit are compared to those of the shell-rich tsunamite from Caesarea, Israel, and resulted in the identification of three generic, tsunamigenic-specific traits in shell beds: 1) thickly bedded and laterally extensive shell deposit, 2) presence of allochthonous articulated bivalves not in life position, and 3) extensive angular fragmentation. When these three traits are found together, a tsunamigenic origin should be considered for the shell bed. The third chapter analyzes the PSD of the tsunamite in eight sediment cores for digested and undigested samples. Cluster analysis of the PSD extended the upper or lower tsunamite contacts in four cores, but in general, the tsunamite thickness is consistent with the previously identified shell beds (Chapter 3). The tsunamigenic processes that resulted in the deposition of the shell bed were complex, and deposition occurred during run-up, flooding, and backwash stages of the tsunami, incorporating marine, lagoonal, and terrestrial (wadi) sediment into the tsunamite. The results of this study provide baseline sedimentological data for an understudied region of the world. New applications of cluster analysis of PSD and taphonomic analysis have the potential to identify previously unknown tsunamites in the geological record, and lithological facies using textural analysis. / Thesis / Doctor of Philosophy (PhD)

<p>Frenchman's Bay is a shallow coastal lagoon (0.84 km2) located near the eastern limits of the Toronto urban area. Wholesale land clearance in the 1850's and subsequent industrialization and urbanization of the watershed have had severely impacted wetland habitats and degraded sediment and water quality. Prior to implementation of remediation work, a detailed sedimentologic and magnetic property study was conducted to determine the impacts of post-colonial land use changes in Frenchman's Bay. 11 vibrocores (2-4.5m length) were extracted from the lagoon and 3 5 magnetic susceptibility profiles were collected using a probe driven 1-2 m in the lagoon floor. The core lithofacies were logged in detail and magnetic susceptibility (K, x.) and remanence parameters (NRM, SIRM, Bcr) were measured at 2 cm intervals. Magnetic property and lithofacies data were integrated with geochemical analyses (TOC, C03) and 210Pb dating of core in order to reconstruct the lagoon lithostratigraphy and the thickness of the post-colonial 'anthropogenic layer'. </p> <p>The stratigraphic succession in the lagoon consists of a thick upper sequence of marly gyttja and peat-rich silty marls overlying Holocene laminated marls. The postcolonial layer (Unit 1) is recognized as an uppermost high magnetic susceptibility (x = ~200-300 xl0-8 m3/Kg) gyttja layer that extends to 1-1.5 m depth. The base of the unit has a 210Pb age of 1850 (±55.6), corresponding with the main phase of land clearance and onset of industrialization of the harbour. Titanomagnetite, maghemite and magnetite spherules are the primary magnetic minerals, indicating soil erosion and coal burning as the predominant sources of magnetic particles. The underlying Unit 2 consists of peaty marls with abundant plant fragments recording a more extensive marsh. Unit 3 consists of more carbonate-rich laminated sands (magnetic susceptibility x = 6000 x10-8 m3/Kg) deposited in a low energy oligotrophic lagoon. The basal layer (Unit 4) consists of high magnetic susceptibility massive pebbly muds, which record a pre-lagoon phase of higher water levels in post-glacial Lake Iroquois (ca. 13,500 Ka). </p> <p> Isopach mapping of the magnetostratigraphic units clearly identifies that the anthropogenic layer (Unit I; post-1850) is thickest within a central basin which has acted as trap for sediment carried into the lagoon by several streams. The total volume of impacted anthropogenic sediment is estimated at 4 x105 m3. Isopach maps also identify two thin(< 2 m) wedges of sand (9.6 x104 m3) near the north and southern shores of the bay that records periodic overwash and growth of the beach barrier. </p> <p>The major environmental changes in the lagoon since it inception (ca. 2. 7 Ka include: 1. The formation of a shallow coastal embayment following water level rise from a mid-Holocene low-stand in Lake Ontario (Unit 4); 2. Development of a spit and beach barrier by eastward longshore transport (Unit 3); 3. Closure of the lagoon and development of a stabilized marsh habitat with low sedimentation levels (Unit 2); 4. Destruction of marsh habitats and eutrophication of the lagoon coinciding with land clearance (post-1850's) and an increased in the influx of sediments eroded from the catchment area. </p> / Thesis / Master of Science (MS)

Diet change over time is assessed for a Malabar II period (900 C.E. to 1565 C.E.) Ais indigenous community in Cape Canaveral, Florida, at the Penny Plot site (8BR158). To this end, 7,760 faunal fragments were examined, with 1,876 identified at the species, genus, or family level. Through identification and analysis of faunal remains, it can be concluded that, while the amounts of overall remains left behind as a whole increased, there were no significant changes in the types of fauna utilized or patterns of consumption. This suggests that the indigenous people who occupied this site managed their resources very effectively for a long period of time and likely passed on management strategies through generations to allow for plentiful food for years. This area of Florida has received little serious attention from scholars in the past, and through studying sites such as the Penny Plot site we are starting to paint a picture of precontact and colonial era Indigenous life in coastal Central Florida. Thus, we are better educating ourselves about the people who came first to Florida and their complex relationship with their surrounding environment, paralleling that of modern Floridians.'

The Indian River Lagoon, Florida, is a unique closed “bar built” estuary system that has little interchange with the Atlantic Ocean and which is home to many resident species. Three fish species were investigated to see if their isotopic and fatty acid signatures differed based on geographic location. The goal was to assess the degree of resolution of spatial variation that is possible when using stable isotope and fatty acid signature analysis to interpret feeding habits and potential linkages between feeding habits and health status. Spotted seatrout (n=40), pinfish (n=60) and white mullet (n=60) were collected over a 4 week period at sites 30 km apart in two distinct biogeographic regions of the IRL. Fish were analyzed for stable isotope (δ13C and δ15N) and fatty acid composition. All three species were significantly different from each other in both isotopic and fatty acid signatures. In the North Indian River segment, spotted seatrout, white mullet and pinfish had mean values (± SE) for δ13C of -18.00 ± 0.08, -14.59 ± 0.07 and -16.88 ± 0.04 respectively and for δ15N, mean values were 14.43 ± 0.05, 8.30 ± 0.04 and 10.43 ± 0.03 respectively. For the North-Central Indian River segment, spotted seatrout, white mullet and pinfish had mean values for δ13C of -18.98 ± 0.02, -16.25 ±0.06 and -16.94 ± 0.04 respectively and for δ15N, mean values were 14.21 ± 0.02, 8.07 ± 0.03 and 10.64 ±0.03 respectively. When species and location interactions were examined using ANCOVA, a post-hoc Tukey’s HSD test showed that δ13C was significantly affected by sampling segment only for spotted seatrout and that there was no significant effect of location on δ15N values. Spotted seatrout was the only species that differed between segments for δ13C. Classification and Regression Tree (CART) analysis was then performed on the “extended dietary fatty acids” for each individual species and collection location. In this analysis, all three species were correctly identified to segment (white mullet - MR 2/53 p~ 0.03; spotted seatrout (MR 0/40), and pinfish (MR 0/56) indicating that individual species were exhibiting significant differences in their fatty acid signature over distances of 30 km. The ability to discern fine-scale differences in potential prey allows for the possibility of better resolution of dolphin feeding habits and hence a better understanding of both habitat utilization and health impacts. Due to limited exchange of clean salt water, contaminants can theoretically become a problem and there are indications that the health of the resident population of bottlenose dolphins (Tursiops truncatus) has been declining over recent years.

Microplastics are widespread and abundant. Few studies have examined the diversity and abundance of microplastics in wild organisms. This study determined the microplastic quantity and types in the organic tissues of the eastern oyster Crassostrea virginica and Atlantic mud crab Panopeus herbstii from the Indian River Lagoon (IRL). This study also investigated whether location affected the microplastic abundance and variety. Organisms were collected from three sites across Mosquito Lagoon in the northern IRL. Oysters were frozen after collection. Crabs were placed in containers for 5 days before freezing. The soft organic tissue was chemically digested using hydrogen peroxide, filtered, and examined for microplastics. Water samples collected from each study site had an average of 23.1 microplastic pieces per liter and fibers were the most common type. There was a significant interaction for microplastic type and site for both oysters and crabs (p