In an age of increasing urbanization, rural communities and agricultural lifestyles are quickly disappearing. Many local, pastoral histories have been buried under the new narratives of modern suburban development. Do such places, located along the rural-urban fringe, contain accounts worth memorializing? This thesis is a case study of the Ancaster Meadowlands—a growing neighbourhood within the City of Hamilton, Ontario. It explores the process of suburban growth and uncovers the local history of a landscape. As a narrative, the study traces land-use change over time, displaying the area’s evolution from a site of Neolithic settlement, to an important Loyalist village, and finally to a large suburban neighbourhood with commercial and residential components. Three principal methods are employed: resident interviewing, key informant interviewing, and archival research. Themes elicited in this study include land-use conflict, NIMBYism, real-estate volatility, and the interconnectedness of politicians and developers. Given that there are few case studies of contemporary suburban development, this study provides a rare illustration of the multi-faceted process of expansion around a Canadian city while also supplying a historical account of local importance. / Thesis / Master of Arts (MA)

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Wetland ecosystems play an important role in the global hydrologic cycle, and their hydrologicregime is a major factor for their general functioning (carbon, biodiversity, biogeochemicalcycle etc.). However, the factors that govern the hydrologic regime of wetlands, such asmoisture imports into their catchments and moisture cycling in wetland areas, remain largelyunderstudied.Wetlands, seen as part of the terrestrial land, often rely on moisture imports from terrestrialevaporation and moisture recycling within their catchments. This could make them especiallysusceptible to changes in their hydrologic regime caused by land cover and hydroclimaticchanges in their catchments. Hence, this study aims to provide an overview of atmosphericmoisture imports into iconic wetlands worldwide and investigates the precipitationsheds of 40globally distributed catchments of Ramsar wetlands.Here we show that some of the wetlands have already been affected by precipitation changescaused by land cover changes within and outside of their catchments, as well as hydroclimaticchanges. According to our analysis, most of the studied wetland catchments show decreases inannual terrestrial precipitation, which are caused by precedent land cover changes. Thestrongest effects are seen in (sub)tropical wetlands in South America, Africa and Asia, andcatchments whose precipitationsheds include large agricultural areas.This shows that land cover changes can cause wetlands to be less resilient under current andfuture hydroclimatic and land cover changes. An overlap of multiple stressors, like climatechange and precipitation changes through land cover conversions, make wetlands in someregions especially vulnerable.Based on our results, current wetland decline rates and predictions of future agricultural andurban expansion, we find that wetland sites in China, India, South America and Sub-Saharanare especially threatened. This study indicates further that we have to incorporate downwindeffects to land cover changes in sustainable ecosystem management approaches.

A fish kill was observed in a historically freshwater region of the Everglades, coinciding with a spike in salinity. Sea level rise and altered hydrology allow freshwater wetland systems to be susceptible to saltwater intrusion. Most wetlands are characterized by highly organic soils with microbial communities starved of oxygen, seeking alternative electron acceptors. Seawater contains sulfate (SO42-), which is one of the alternative electron acceptors. Provided with sufficient quantities, sulfate-reducing bacteria (SRB) outcompete other anaerobes and produce toxic hydrogen sulfide. This study asked, what combination of soil organic matter (SOM) and SO42- are needed to produce sulfide concentrations potentially lethal to freshwater fish? Soil samples were collected from two freshwater wetlands with varying SOM content and incubated in microcosms at four SO42- concentrations (0, 0.75, 4.0, and 12.0 mM Na2SO4). Sulfide concentrations produced were compared to published data on lethal sulfide toxicity levels for aquatic life. This study demonstrated that high SOM soils (89.3 ± 0.2 % moisture) incubated with SO42- concentrations > 0.75 mM, rapidly produced toxic sulfide concentrations (> 5 ppm S2-) within 24 hrs.. While many freshwater species may tolerate a salinity of 1 ppt (0.75 mM SO42-), this SO42-concentration is sufficient to support SRB and lead to toxic sulfide production. ese results support the need to restore freshwater hydrology in wetland systems, such as the Everglades, thereby protecting against the rapid ecological effects of saltwater intrusion.

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Coastal restoration has become a necessary and ubiquitous practice to enhance and conserve the many ecosystem services lost by marsh degradation. Wave climate is one of the most critical factors to consider for restoration projects. However, knowledge of the ways that waves affect marsh plants and the ecosystem services they provide is limited. The purpose of my dissertation was to improve the effectiveness of coastal marsh restoration by addressing the limitations and gaps associated with plant and ecosystem responses to waves through empirical research with three primary goals: 1) develop and test a low-cost wave gauge, 2) use it to compare above- and below-ground plant growth responses along a wave climate gradient, and 3) evaluate the effects of waves on nutrient removal in constructed marshes. I used three field and laboratory experiments to accomplish these goals. The low-cost wave gauge was developed using an Arduino microcontroller and various accessories. After development, the gauge was evaluated against a commercial gauge in a series of laboratory and field tests. Comparisons revealed over 90% agreement between the gauges and confirmed the applicability of the low-cost gauge. A total of thirty gauges were then constructed and deployed at sites within Mobile Bay, Alabama and surrounding tributaries. In addition to wave energy, plant data was also collected at each site, including above- and below-ground biomass, shoot density, height, and diameter. These data suggested that waves affect plant growth responses in ways not explained by the current plant response paradigm. For example, while greater diameter shoots best attenuate waves, shoot diameter declined with greater wave exposure in this study. This response was common among the study species. Other plant responses were species-specific. Finally, a field experiment was constructed to examine the main and interactive effects of sediment type, initial planting density, platform slope, and platform position at sites exposed to and protected from waves. Results from this experiment suggested that waves may potentially mitigate the effective removal potential of constructed marshes. Taken together, this dissertation advances research on plant responses to waves and provides new tools for land managers working on coastal restoration and conservation projects.

Precipitation over coal fly ash surfaces raises concerns about potential downstream impacts of dissolved selenium (Se) on aquatic ecosystems. Detention ponds hold runoff until aqueous Se concentrations meet water quality regulations: within 10 days, 90% of runoff must be discharged and cannot exceed 11.8 μg Se L-1 (ppb). Constructed wetland (CW) phytoremediation is a potential treatment option to meet these regulations. This research was conducted to 1.) Assess the potential of native southeastern aquatic macrophytes for Se tolerance and removal efficiency compared to unplanted (UNP) detention ponds; 2.) Evaluate seasonal influence on Se removal in CWs over four, weekly flood-discharge cycles; and 3.) Determine the effect of temperature on aqueous Se removal. Monoculture CW microcosms (110 L) were flooded six days with 500 or 1000 ppb Se, as selenite (SeO32-) or selenate (SeO42-) evaluating five plant species for Se tolerance. Seasonal evaluations were conducted with cattail (Typha angustifolia L.; CAT) and duckweed (Lemna minor L.; DWD) over four weekly flood-discharge cycles at 16 or 32 ppb SeO42--Se. Cattail, DWD, or UNP volatilization chambers (VCs) flooded with a 3 L solution at 35 ppb SeO42--Se were evaluated under 12 h photoperiod at either 20 or 30°C. All experiments contained a zero Se control. Water, plant, and soil total Se concentrations were determined by inductively coupled plasma-mass spectroscopy (ICP-MS) and analyzed with PROC GLM (SAS EG 7.1) at α=0.05. Cattail and DWD were selected for further evaluation with SeO42--Se. The greatest aqueous Se removal was observed in the summer (73%), followed by the fall (42%) and spring (41%), compared to winter (18%). Temperature was strongly correlated with Se removal (0.65, P<0.0001). Except for summer, after two flood-discharge cycles, CAT and DWD improved aqueous Se removal compared to UNP controls. Volatilization chamber data indicated greater Se removal at 30 (69%) compared to 20°C (54%). At 30°C, DWD decreased aqueous Se concentrations below 11.8 ppb Se within 10 days. Given their efficacy and abundance, CAT and DWD are deemed suitable species for phytoremediation in CWs supplied with Se-impacted waters.

I conducted surveys of amphibian, reptile, and small mammal communities surrounding 4 isolated, upland and 6 stream-connected temporary wetlands on Tombigbee National Forest and Noxubee National Wildlife Refuge in north Mississippi from May 2001 - March 2006. Trap captures yielded 17 amphibian species (n = 11,142), 21 reptile species (n = 541), and 10 small mammal species (n = 472). Upland pools supported greater diversity of Ambystomatid salamanders, anurans, lizards, and mice (Peromyscus spp.), than floodplain pools. Factors including landscape position of pools, proximity to alternate water sources, and barriers to dispersal potentially influenced faunal communities of temporary wetlands. Infrared-triggered cameras were used to monitor mammalian activity surrounding ephemeral wetlands to determine potential depredation of pitfall traps. Raccoons (Procyon lotor) accounted for most images (35% total images). I assessed relative effectiveness of sampling techniques to capture and retain herpetiles in presence of depredation. I tested pitfall trap, funnel trap, and pitfall trap combined with exclusion cover along driftence arrays. Overall, pitfall traps of both designs produced more captures than funnels, and excluded-pitfalls yielded greater captures than un-excluded pitfalls for most amphibians. Overall mortality rates were <2% of total captures with anurans accounting for most (63.30%) mortality. I submit that in long-term studies, pitfall traps with exclusion are prudent to limit sampling bias and mortality occurring with depredation of captured herpetofauna. During trapping, pit-traps of both designs yielded incidental captures of small mammals. Capture rates for small mammals were similar in un-excluded pitfall traps and excluded pitfall traps. Southern short-tailed shrews (Blarina carolinensis) and mice accounted for 93% of total captures and suffered 76% and 52% mortality, respectively, potentially due to exposure, starvation, flooding, and/or depredation. Additionally, one species listed as rare in Mississippi was captured during herpetofaunal surveys, oldfield mouse (Peromyscus polionotus). Due to potential impact of pitfall trapping on small mammals, I recommend that researchers either alter trapping methods to address non-target hazards (frequency of checking traps, providing shelter) or work cooperatively using an integrated survey approach for herpetiles and small mammals to limit trap mortality.

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