This thesis uses the popular genre of detective fiction to explore the context of the heyday of the crime genre: the Golden Age. This sub-genre, best known for producing Agatha Christie, spanned the complicated history of Britain involving the Great Depression, two World Wars and huge changes to class structure. It is for these reasons that the Golden Age is such a pivotal period for changing notions of British identity. Through the very British Christie and the less well known New Zealander, Ngaio Marsh, expressions of national identity are explored as well as how the colonial fits in. Focusing heavily on the authors and their own personal experiences and views, this thesis is divided into four chapters to further break down how the Golden Age period affected its citizens and why this detective fiction held such a wide appeal. Chapter one explores gender roles and how Golden Age authors both conformed to them through their choice in detectives, yet also how they naturally resisted some through their own public image. Chapter two then examines the issue of class and how Golden Age detective fiction portrayed the changes. Contrary to popular criticism, Christie and Marsh were surprisingly progressive and forward thinking on this subject. Chapter three considers how both authors employed setting to emphasise these changes. Both Christie and Marsh used foreign settings to highlight British society and its flaws, and Marsh used her New Zealand settings to consider the relationship between Britain and her home. The final chapter will consider why Golden Age detective fiction was so popular: what was the appeal? For a period of violence and uncertainty, why were people drawn to crime fiction involving sometimes gruesome death? The appeal lay, and still does, in the puzzle: the game that diverted readers from their own problems. Golden Age fiction may have been highly formulaic and predictable, but it was also highly artificial and self-referential. This was a clever and diverting fiction that has been constantly underestimated by critics and deserves further study.

Cattails (Typha spp.) are invasive and tend to decrease the biodiversity and area of open water of marshes, particularly where the natural hydrological cycles have been altered, as in Delta Marsh, Manitoba. Understanding the distribution of T. latifolia L., T. angustifolia L., their hybrid, T. x glauca Godr., and the environmental variables associated with their habitats, may give valuable insight for managing cattails. The distribution of these cattail species and hybrid were surveyed in 2011 in prairie pothole and roadside ditch marshes across southwestern Manitoba and southeastern Saskatchewan. Plants were identified by analysis of microscopic leaf-lamina margin characteristics. T. x glauca was most widespread, followed by T. latifolia, whereas T. angustifolia was rare and only found as far west as central Manitoba. Current understanding of the correlations between cattail invasions and their environment is conflicting and largely based on lacustrine wetland studies. A generalized linear model was developed. The model explained approximately 40% of the variation in T. x glauca distribution in the prairie potholes and ditches. The model included the environmental variables of sediment Olsen-P, sediment nitrate-N, water pH, litter depth, surrounding land use, and the interaction between Olsen-P and nitrate-N. Olsen-P was the most important of these variables, because its removal from the model significantly reduced the residual deviance of the model (P=0.05). In a survey of 13 transects throughout Delta Marsh in 2009, hybrid cattail, T. x glauca, was dominant, T. angustifolia was rare, and T. latifolia was absent. ANOVA linear regression (P=0.05) revealed that above-ground biomass was correlated with mean cattail ramet height, cattail ramet density, and standing litter biomass. Cattail ramet density was negatively correlated with sampling date and positively correlated with standing litter biomass. Mean cattail height was correlated with fallen litter biomass. One-way ANOVA (P=0.05) revealed that fallen litter biomass was lowest in quadrats closer to the open water, and mean cattail height was greatest at the quadrats closest to the open water. While mean cattail height differed depending on whether the cattail stand was a hybrid monoculture or a mixed stand of T. x glauca and T. angustifolia, no other cattail population variables were correlated with stand type. As revealed by one-way ANOVA (P=0.05), water conductivity, sediment texture, total-N, nitrate-N, Olsen-P, and organic-C were not important variables in the distributions of T. x glauca or T. angustifolia at Delta Marsh. Therefore, managing the nutrient levels at Delta Marsh would not likely be important for limiting the distribution of the cattails at this marsh. However, reducing the P concentration in pothole and ditch marshes may limit cattails in those environments.

High levels of phosphorus loading in Lake Winnipeg, Manitoba, Canada are causing eutrophication and algal blooms of increasing intensity and frequency. Phosphorus is also a strategic and limited natural resource critical for plant growth, and essential for agriculture and global food security. This research study demonstrated an innovative environmental engineering approach to address multiple sustainable development challenges. Cattail (Typha spp.), a large competitive emergent aquatic plant, was harvested to capture and remove nutrients that would otherwise cause eutrophication in aquatic systems, and utilized as a biomass material for industry. Cattail reaches maturity in less than 90 days, and late summer/early fall harvests yielded average 15 to 20 t DM/ha, and captured 30 to 60 kg/ha/year of phosphorus. Once harvested, nutrients locked in plant tissue are prevented from being released into the environment via natural decomposition. Utilizing harvested biomass as a bioenergy feedstock provided a further benefit displacing fossil fuels for heating, and generated valuable carbon offsets. Cattail was compressed into densified fuel products, and combustion trials revealed an average calorific heat value of 17 MJ/kg to 20 MJ/kg, comparable to commercial wood pellets. Average ash content was 5 to 6%, and no major concerns identified regarding combustion emissions and ash. Estimated greenhouse gas (GHG) mitigation potential from coal displacement was one tonne of cattail biomass generated 1.05 tonnes of CO2 offsets. Additionally, up to 88 % of total phosphorus was recovered in ash following combustion in solid fuel burners. Harvesting cattail biomass offers greatest feasibility if combined for multiple purposes: nutrient capture, habitat, bioenergy, carbon offsets, water quality credits, and higher value end products and biomaterials (i.e. biochar). Economics of harvesting need to be further explored at the pilot and commercial scale for this novel renewable and sustainable ecological biomass feedstock. From an agricultural context, this biomass resource is presently undeveloped. It is a plant species prized for its nutrient capture and water quality benefits, and a biomass feedstock for bioenergy and high value end-products that grows on marginal agricultural land, not competing with prime land and food crops.

Common carp (Cyprinus carpio) have been hypothesized to contribute to declines in aquatic macrophytes, waterfowl, and water clarity in Delta Marsh, an 18,500 ha freshwater coastal wetland on Lake Manitoba, Canada. Ten ponds (1-13 ha) were chosen for a two-year experimental manipulation study. Following a year of baseline monitoring, manipulations were conducted in 2002. To facilitate access by carp into isolated ponds, channels were blasted from the main marsh into two ponds. Meanwhile, to restrict or exclude carp access into ponds, channels were either screened or diked to four ponds. Two connected and two isolated ponds functioned as controls. Although common carp were the original subject of the study, it became apparent that hydrological connection to the surrounding marsh had a paramount importance on the abundance and diversity of the fish, amphibian and water-column invertebrate communities. Connectivity, or lack of connectivity, played an important role in the distribution of the fish community, and subsequently the composition and abundance of water-column invertebrates and amphibians. Ponds with direct connection had diverse, mixed-species fish assemblages, with fewer invertebrates and amphibians. Ponds with restricted connections had fish communities composed of tolerant small-sized species and increased abundance of invertebrates and amphibians. Ponds that lacked connection could freeze and lose all fish, and had higher numbers of invertebrates and amphibians. An absence of adult common carp may have been responsible for increased amphibian numbers in the screened ponds, however more study is needed. Confounding impacts of fluctuating water levels made it impossible to implicate common carp for most changes observed within ponds in Delta Marsh.

Common carp (Cyprinus carpio) have been hypothesized to contribute to declines in aquatic macrophytes, waterfowl, and water clarity in Delta Marsh, an 18,500 ha freshwater coastal wetland on Lake Manitoba, Canada. Ten ponds (1-13 ha) were chosen for a two-year experimental manipulation study. Following a year of baseline monitoring, manipulations were conducted in 2002. To facilitate access by carp into isolated ponds, channels were blasted from the main marsh into two ponds. Meanwhile, to restrict or exclude carp access into ponds, channels were either screened or diked to four ponds. Two connected and two isolated ponds functioned as controls. Although common carp were the original subject of the study, it became apparent that hydrological connection to the surrounding marsh had a paramount importance on the abundance and diversity of the fish, amphibian and water-column invertebrate communities. Connectivity, or lack of connectivity, played an important role in the distribution of the fish community, and subsequently the composition and abundance of water-column invertebrates and amphibians. Ponds with direct connection had diverse, mixed-species fish assemblages, with fewer invertebrates and amphibians. Ponds with restricted connections had fish communities composed of tolerant small-sized species and increased abundance of invertebrates and amphibians. Ponds that lacked connection could freeze and lose all fish, and had higher numbers of invertebrates and amphibians. An absence of adult common carp may have been responsible for increased amphibian numbers in the screened ponds, however more study is needed. Confounding impacts of fluctuating water levels made it impossible to implicate common carp for most changes observed within ponds in Delta Marsh.

Little is known about the distribution and habitat suitability of yellow rails (Coturnicops noveboracensis) throughout their breeding range. Yellow rail and vegetation surveys were conducted at 80 wetlands in south-central Manitoba in 2010-2011 to evaluate the effectiveness of repeat-visit, call-broadcast night surveys for detecting this species and habitat associations of this species at the 3-km landscape, patch, and plot scales. Yellow rails were detected at 44% of the study wetlands. Yellow rail detection was imperfect (0.63 in each year), but call-broadcast increased the number of yellow rails detected. Future yellow rail survey efforts should employ call-broadcast and at least three surveys per survey point. Yellow rail presence was positively influenced by the amount of marsh/fen in the landscape and the proportion of rushes at the study wetlands. These characteristics should be considered when identifying potential yellow rail habitat in south-central Manitoba.

Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 98-106). / vii, 106 leaves, bound 29 cm

This thesis documents the work undertaken to investigate and improve the theoretical and practical requirements for two-dimensional hydrodynamic modelling of coastal and estuarine areas, in particular to the inter-related aspects of: - wetting and drying of relatively large intertidal areas, and - the influences of waves on both current generation and variations in mean water level. The work outlined in this thesis began as a result of a perceived lack of understanding and confidence in the application of finite element models to coastal and estuarine situations. In response to this observation an investigation into the modelling parameters, particularly those that affect model performance during the simulation of wetting and drying, was undertaken. This initial investigation into the effect of these parameters upon model performance forms the first component of this study. Testing was performed to provide a quantitative assessment of the effect of these parameters upon model performance. The initial tests were simple examples designed to investigate the behaviour of a single specific parameter. Subsequent tests were more complex and assessed the combinations of various parameter selections. Once the model was shown to accurately simulate the movement of waters in a coastal and estuarine environment, wave forces were incorporated. The aim of the second component of the study was to modify the hydrodynamic model to predict the net current and water levels attributable to the influences of waves. Tests examined the effects of the application of wave induced forces in a range of applications, including the simple case of a uniform beach, comparisons to a physical model, and an example from a real coastline. The final outcome of this study is the development of a modelling tool that can accurately represent the forces of tides, winds and waves upon water movement in a shallow coastal and/or estuarine region. Furthermore, the qualitative and quantitative assessments of parameters that affect the performance of the model provide greater confidence in model results and better understanding of the applicability and limits of the modelling technique. Principal outcomes of the study are: - an improved understanding of the parameters which influence the behaviour of hydrodynamic models; - a better understanding of the applicability and limits of the modelling technique; and - an enhanced software system based on an existing modelling software system which is applicable to studies that require simulation of the combined forces of tides, winds and waves.

Thesis (M.S.)--University of North Carolina Wilmington, 2008. / Title from PDF title page (viewed September 22, 2008) Includes bibliographical references (p. 60-62)

Thesis (Ph. D.)--Florida State University, 2005. / Advisor: Dr. Joel Kostka, Florida State University, College of Arts and Sciences, Dept. of Oceanography. Title and description from dissertation home page (viewed June 22, 2005). Document formatted into pages; contains xi, 108 pages. Includes bibliographical references.