Consistent shoreline development and urbanization have historically resulted in the loss of wetlands. However, some construction activities have inadvertently resulted in the emergence of new tidal wetlands, with prominent examples of such anthropogenic wetlands found within the Hudson River Estuary. Here, we utilize two of these human-induced tidal wetlands to explore the sedimentary and hydrologic conditions driving wetland development from a restoration perspective. Tivoli North Bay is an emergent freshwater tidal marsh, while Tivoli South Bay is an intertidal mudflat with vegetation restricted to the seasonal growth of aquatic vegetation during summer months. Using a combination of sediment traps, cores, and tidal flux measurements, we present highly resolved sediment budgets from two protected bays and parameterize trapping processes responsible for their divergent wetland evolution. Utilizing a 16-year tidal flux dataset, we observe net sediment trapping in Tivoli North for most years, with consistent trapping throughout the year. Conversely, sediment flux measurements at Tivoli South reveal net sediment loss over the study period, with trapping constrained to the summer months before being surpassed by large sediment exports in the fall and early spring. The timing of the transition from sediment import to export marks the end of the invasive water chestnut growing season and the onset of the associated exodus of both sediment and organic material from Tivoli South. When sediment cores collected for this study are compared to sediment cores collected in 1996, 137Cs profiles confirm little to no sediment accumulation in Tivoli South over the previous two decades. These results support the hypothesis that water chestnut is serving to inhibit sediment trapping and facilitate sediment erosion, preventing marsh development in Tivoli South. The longevity of this dataset highlights the capacity of aquatic vegetation to regulate sediment exchange and geomorphology in enclosed bays when provided an opportunity to colonize. Results of this project provide evidence to inform the management of restoration projects in river systems with freshwater tidal wetlands, especially those affected by invasive species of aquatic vegetation. In bays where tidal sediment supply is not limited, water chestnut removal may present a viable strategy to facilitate marsh restoration.

Salt marshes are important habitats that provide many ecosystem services, but they are susceptible to the impacts of sea level rise (SLR), often resulting in emergent vegetation loss. In areas with enough sediment input, marshes can keep pace with SLR by gaining elevation or through upland migration. However, salt marshes in areas with limited sediment input, such as the Grand Bay National Estuarine Research Reserve, often cannot keep pace with sea level rise. Additionally, the rate of SLR is increasing making it more difficult for marshes to keep pace. To assess the short-term response of marsh vegetation to sea level rise, percent cover, stem density, and elevation, data from 2016 to 2020 in four different marsh elevation zones were analyzed in this study. Results demonstrated that the four marsh elevation zones are responding disparately to SLR. These findings indicate that it is imperative to implement restoration plans to account for site variability to conserve these vital habitats.

Wastewater effluent is a major source of aquatic pollution, discharging a continuous and complex mix of contaminants into the environment. The physiological impacts of exposure to individual contaminants are well characterized in fish, but less is known about the consequences of complex mixtures that typify wastewater effluent in the environment. This thesis explores the metabolic and respiratory effects of in situ wastewater exposure on bluegill sunfish (Lepomis macrochirus). By assessing multiple levels of biological organization, I provide evidence that wastewater exposure invoked a metabolic cost in bluegill, which was associated with physiological adjustments to enhance oxygen uptake, delivery, and utilization. These findings broaden our understanding of how fish tolerate life in effluent-dominated waters and support the emergence of metabolic and respiratory physiology as biomarkers in ecotoxicology. / Thesis / Master of Science (MSc)

No description available.

Late nineteenth-century Victorian adventure novels offer a complex depiction of manhood in relation to colonial adversaries. H. Rider Haggard's 1880s novels portray imperial adventure as an opportunity for masculine rejuvenation, while later adventure novels express a sense of imperial dread and suggest that adventure traumatizes, instead of rejuvenates, masculinity. All of these novels offer insight into a larger shift in Victorian thought concerning Britain's role as an imperial power. The novels define masculinity in two distinct ways: as modern and as medieval. Each novel approaches modern manhood as impotent when faced with the colonial threat, but the narratives all offers a different interpretation of medieval masculinity, underscoring the vexed nature of the Victorian's relationship with the past. H. Rider Haggard's novels, King Solomon's Mines (1885) and She (1887), suggest that imperial adventure offers modern manhood rejuvenation and purpose through interaction and eventual suppression of the colonial female. Haggard offers an optimistic portrayal of adventure because of both the men's distinctly medieval form of physical rejuvenation and the men's ability to influence the landscape in their favor. Authors Bram Stoker and Richard Marsh present a vastly different interpretation of empire and medieval masculinity in their 1897 novels Dracula and The Beetle. Adventure traumatizes the men in the later novels, and their hysteria attests to their effeminate lack of masculine virility. The 1897 novels critique both the optimistic depiction of imperial adventure and the unnatural reliance on medieval forms of masculinity offered in novels such as Haggard's.

Settlers of the Marsh est un roman migrant et un récit d'édification nationale. Niels Lindstedt, le protagoniste, est un jeune Suédois immigré au Canada, qui, pendant une longue période de temps, subit un processus de transformation qui aboutit par une Canadianisation totale. Son expérience d'immigrant est déchirante et le prix qu'il doit payer est très élevé. Le déracinement de Niels dû à sa migration et son enracinement ultérieur au Canada font l'objet d'un récit détaillé. L'histoire de Niels est, jusqu'à un certain point, une preuve de l'investissement de l'auteur lui-même dans le Canada. Le texte foisonne des échos de la vie de Frederick Philip Grove et de ses sympathies développées lors de son travail pour le compte des nouveaux arrivants non-Britanniques. Ces échos façonnent la perception qu'a Niels de son nouveau milieu environnant. En séparant les faits de la fiction, on peut remarquer que l'histoire de Niels est racontée alternativement par les avatars assumés ou cachés de Grove. Ces différentes voix créent des significations inattendues pour les lecteurs d'aujourd'hui, tout en révélant les efforts de Grove de médier entre les anciens et les nouveaux Canadiens dans les années 1920. Un roman complexe aux messages codifiés, Settlers of the Marsh parle, au nom des immigrants, de leur but ultime: le besoin de se trouver leur propre petit monde. / Settlers of the Marsh is an immigrant novel and a nation-building story. Niels Lindstedt. the protagonist, is a newcomer to Canada who, over an extended period of time, goes through a process of transformation that culminates in his complete Canadianization. His immigrant experience is heartbreaking and the price he pays very high. Niels's uprooting from Sweden and his subsequent rerooting in Canada is recorded by the narrator in detail. Niels's story is, to a certain degree, a testimony to the author's investment in Canada. Frederick Philip Grove's life story and his sympathies developed during his work experience on behalf of the non-British newcomers to Canada resonate throughout the text and shape Niels Lindstedt's perception of his new surroundings. Separating fact from fiction, one is able to see that Niels's story is told alternately by Grove's assumed and concealed personae. These different voices create unexpected meanings for today's readers, revealing Grove's efforts to mediate between old and new Canadians in the 1920s. A complex novel, with encoded messages, Settlers of the Marsh speaks, on behalf of immigrants, of their ultimate goal: the need to find one's own little world.

Tidal marsh and its bird community across the northern Gulf of Mexico are subject to numerous disturbances such as oil spills, hurricanes, habitat loss from land use change, and high relative sea level rise rates looming in the future. Baseline population data and landscape associations are greatly needed to assess the current distribution and the future impact of perturbations on marsh birds across the Mississippi Gulf Coast. Using a standardized sampling design and point count survey protocol, we determined the abundance and population size of Clapper Rails, Common/Purple Gallinules, Least Bitterns, Marsh Wrens, Seaside Sparrows, Red-winged Blackbirds, and Common Yellowthroats across the Mississippi Gulf Coast. With abundance models for each species in 2021 and 2022, we further investigated the impact of important fine and broad scale landscape variables that affected species-specific abundance across variable marsh complexes. Finally, we generated species distribution maps based on our spatially-explicit baseline population estimates.

Salt marshes provide critical ecosystem services, such as shoreline stabilization, biogeochemical cycling and habitat for wildlife, to much of the world's population living on the coasts. Emergent vascular plants are a critical component of these ecosystems. This study was a comprehensive effort to gain a better understanding of the ecology of salt marsh plants in the Nueces River delta on the south Texas coast. This knowledge is essential to understand the potential anthropogenic impacts on salt marshes, including sea-level rise, global warming, reduced freshwater inflow and coastal erosion. A combination of remote sensing analysis, field studies and experiments were used to allow analysis across spatial scales ranging from landscape patterns of vegetation to leaf level measurements of the dominant species. A novel method of image classification was developed using high-resolution multi-spectral imagery integrated with ancillary data to map the major plant communities at a landscape scale. This included a high marsh assemblage composed primarily of Spartina spartinae and a low marsh community dominated by Borrichia frutescens and Salicornia virginica. Geospatial analysis determined that the location of these plant communities was related to the distance from the tidal creek network and elevation. The B. frutescens and S. virginica assemblage was more abundant at lower elevations along the waters edge, making it vulnerable to loss from shoreline erosion. At a finer spatial scale, gradient analysis was utilized to examine the relationship between elevation, which creates environmental gradients in salt marshes, and species distribution. I discovered that elevation differences of less than 5 cm can influence both individual species and plant community distribution. One interesting finding was that the two dominant species, B. frutescens and S. virginica, share similar responses along an elevation gradient yet are observed growing in monotypic adjacent zones. I constructed a large reciprocal transplant experiment, using 160 plants at 4 sites throughout the marsh, to determine what causes the zonation between these two species. The results of this study found that S. virginica fared well wherever it was transplanted but was a weak competitor. B. frutescens survival was significantly lower in the S. virginica zone than in its own zone suggesting that abiotic factors are important in determining the zonation of this species. However, high spatial and temporal variability existed in environmental parameters such as salinity. This variability may have been caused by the semi-arid climate and irregular flooding typical in the Nueces Marsh. Therefore, I utilized a greenhouse experiment to directly test the importance of the two dominant physical factors in salt marshes, flooding and salinity. The results found that for B. frutescens the effects of flooding were not significant, however salinity at 30% reduced growth. Salinity did not influence growth of S. virginica. The greater ability of S. virginica to tolerate salinity stress has important implications because reduced freshwater inflow or climate change can increase porewater salinity, thus favoring the expansion of S. virginica, and altering the plant community structure. / text

Les marais salés de la Baie du Mont-Saint-Michel forment un écosystème complexe et fragile. Afin de mieux comprendre l'organisation spatiale de la végétation de ces marais et de développer une vision synthétique de la dynamique de ce milieu, des données de télédétection optiques (orthophotographie) et altimétrique (LiDAR), ainsi que des observations de terrain ont été réunies et traitées conjointement. Le contrôle qualité des données LiDAR ayant mis en évidence un biais systématique dépendant de la hauteur et de la densité de la végétation, une correction, consistant à assigner à chaque pixel la valeur LIDAR minimale au sein d'un carré de 3x3 m, a été appliquée. Une importante base de données spatialisées a ensuite été constituée, comprenant la description en termes de végétation, d'altitude, de géomorphologie, de sédimentologie et d'utilisation agricole de près de 10 000 points d'observation répartis sur l'ensemble de la Baie. Des analyses fréquentielles ont permis de quantifier les liaisons entre les différentes espèces végétales, afin de définir les associations végétales caractéristiques des marais salés. Cette méthode a également permis de dresser la liste exhaustive des liaisons statistiques entre toutes les espèces végétales de la Baie du Mont-Saint-Michel et quatre facteurs écologiques : l'altitude, la géomorphologie, le contexte sédimentaire et le pâturage. Les variations de l'altitude moyenne des espèces végétales à l'échelle de la Baie s'expliquent par l'existence d'une double pente hydraulique qui engendre des altitudes plus élevées à l'Est et à l'Ouest de la Baie. Le contexte géomorphologique et le pâturage peuvent également modifier les valeurs d'altitude moyenne des espèces végétales, et profondément perturber le schéma classique des marais salés. La connaissance des liaisons entre les espèces végétales et les valeurs des facteurs écologiques peut constituer une aide importante à la cartographie des marais salés / In the Mont-Saint-Michel bay, the tidal salt marshes, also called schorre, are made up of low and dense vegetation, that is adapted to tidal flooding and high salinity, and that spreads quickly on the upper tidal flat. The study of this phenomenon requires a map of the vegetation and a simple way to update it. The aim of this study is to evaluate the potential of LiDAR data to enhance the comprehension of this ecosystem. The LiDAR data was first corrected from the systematic error due to the low vegetation that stops the laser beams before they reach the ground. A spatial data base was then created from 9811 observation points, including information on vegetation, altimetry, geomorphology, sedimentology and land use. Frequency analyses were performed on three locations characterized by different geomorphology, sedimentology and land use contexts, and in a second time at the scale of the entire Bay. The vegetation associations of the salt marsh were described, and the relations between each plant species and four ecological factors (altimetry, geomorphology, sedimentology and land use) were investigated. This study has shown the need to include in the mapping process of salt marsh vegetation LiDAR data as well as information on geomorphology, sedimentology and land use

Botanical gardens perform a wide variety of functions, from which one of the most important is an educational function. They provide to visitors a large range of services such as guided tours, a variety of educational programs, worksheets etc. The same applies to the Botanical garden of Faculty of Science, Charles University in Prague. The main aim of the thesis was to prepare worksheets concerning expositions of aquatic and marsh plants in already mentioned botanical garden, verify them on students and adjust them to final forms. The results of the thesis are two different versions (spring and autumn) of the worksheets as well as author's solution and methodological manual for teachers. Within the thesis I also implemented the questionnaire survey where I dealt with the issue of teaching the theme of aquatic and marsh plants at Czech grammar schools and examined the attitude of teachers to field trips during botany teaching. Key words: botanical garden, worksheet, aquatic and marsh plants, field trip, questionnaire