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This study was a comparative study of Plankton of Lake Dallas and the three main source streams. Based on the analysis of data, which was presented relative to the organisms taken from the lake and from the source streams, the results obtained are discussed, the Plankton seem to be largely autogenetic in Lake Dallas, the source streams Elm Fork and Clear Creek form a dilution process.

No description available.

No description available.

Bitumen exploitation in Alberta’s oil sand region generates considerable amounts of waste including tailings and process-affected water that needs reclamation. Water capped tailings technology (WCTT) is currently being assessed as a potential wet reclamation strategy in the oil sand by the commission of Base Mine Lake (BML), the first commercial scale Pit Lake. Pit Lakes consist of ~40m of fluid fine tailings (FFT) deposited in old mine pit covered with a ~10m water cap. In order to be successful, pit lakes much achieve the ecological roles of a natural lake, which includes colonization of the water by macrofauna therefore necessitating the water cap to be oxic. Due to the reductive nature of the tailings, oxygen consuming constituents (OCC) such as methane, sulfide and ammonia are released from the FFT into the water cap potentially posing a threat to the success of the reclamation. Additional seasonal effects such as stratification and ice cover may further affect oxygen consumption by isolating parts of the water cap therefore allowing accumulation of OCC. Results shows that BML thermally stratifies during the summer and winter and that oxygen persist throughout the water cap despite reaching low level at the FFT-water interface (FWI) during summer. Consistent with the FFT acting as an OCC source, aqueous CH 4 and NH 4+ concentrations were highest closer to the FWI, decreasing upwards into the water cap. Using linear regression CH 4 was shown to be an important OCC during the summer of 2015 while NH 4+ and CH 4 were both important for the summer of 2016 highlighting the emergence of nitrification in BML. Detailed analysis of seasonal data revealed that accumulation of OCC below the hypolimnion depletes oxygen and favors methanotrophic activity. Results from both studies suggest that methanotrophs have a competitive advantage at low oxygen levels against nitrifiers. / Thesis / Master of Science (MSc) / Bitumen extraction in Alberta’s oil sand region generates substantial amounts of waste including tailings that needs reclamation. Pit Lakes have been proposed as a reclamation strategy, where tailings are deposited into a mined-out pit and covered with a water cap. To achieve the reclamation goal, the lake must be able to sustain life and must therefore maintain an oxic water cap. The underlying tailings poses a threat to the oxygenation of the lake because of the constant release of compounds that have the potential to consume oxygen. Additional seasonal effects due to temperature change may further affect oxygen consumption by isolating parts of the water cap. In this thesis the results of two years of field sampling and analyses show that despite active oxygen consumption from tailings-released compounds, oxic status is achieved in the upper layer of the lake during summer and under ice.

The dry weight of zooplankton is an important parameter conventionally used to estimate secondary production in aquatic ecosystems. Estimates of zooplankton weight vary considerably across studies. This study examines various factors that contribute to differences in the individual dry weight of freshwater herbivorous zooplankton. In the first chapter, I quantified and compared the individual length and weight changes of Daphnia catawba and Diaptomus minutus resulting from preservation in either 4% sugar-formalin, 70% ethanol solution or freezing over dry ice. The results indicate that the dry weight of both animals was significantly altered by chemical preservatives. The length of Diaptomus was also significantly reduced due to preservation. Site-specific differences in lakes, such as available food and the presence of predators, introduce another potential source of variation in herbivore dry weight. In Chapter 2, the food available to several herbivorous zooplankton in two softwater lakes was estimated using various methods. An index of "edible" phytoplankton biomass based on stomach content analyses was developed and compared to the traditional techniques used to estimate available food. The results indicate that the available was food different for each herbivore and that estimates of food available based on stomach content analyses were not significantly related to the traditional techniques used to estimate available food. In Chapter 3, I evaluate the relative impacts of "topdown" (predation) versus "bottom-up" (food) effects on the dry weight of several herbivores in two softwater lakes with contrasting food-web structures. The length-specific dry weights of Daphnia catawba, Diaptomus minutus and Holopedium gibberum varied seasonally and these changes were taxa-specific and unique to each lake. Herbivore weights were regressed against length, available food, clutch size, population density and temperature to determine if "bottom-up" effects could explain between-lake differences in herbivore weight. Length and population density were the prominent predictor variables in the resulting regression models for the herbivores in these lakes. Predator effects were determined by comparing if the between-lake differences in herbivore weight were consistent with the presence or absence of planktivores. Holopedium dry weight was lower in the presence of planktivores, while Diaptomus dry-weight differences exhibited no consistent trend with the presence or absence of planktivores. / Thesis / Master of Science (MS)

The Belmont Lake conglomerate belonging to the Grenville Supergoup in southeastern Ontario was studied. The conglomerate is interbedded with graded siltstones, mudstones, sandstones, and carbonates, and is associated with what are possibly island arc volcanic cycles. Petrographic study has shown the conglomerate contains tuffaceous, intermediate volcanic, and a variety of sedimentary clasts. In addition both field and petrographic studies show that the conglomerate was derived from a local source -- most likely from the top of the third volcanic cycle and its associated sediments. The depositional environment of the conglomerate is presently unclear, but the overall stratigraphic context of the conglomerate seems to indicate a shallow water environment. / Thesis / Bachelor of Science (BSc)

The object of this thesis is a modestly scaled house at Smith Mountain Lake. The objective of this thesis is to please the senses through material composition. We gain knowledge and sensible understanding of our world through physical interaction and direct sensory experience. Through touching, smelling, listening, and observing we form and guide our choices. These experiences enrich the designer's knowledge of material properties and thus the proper use of materials. The primary focus of this study seeks to understand the physical properties of materials in relation to a site and to each other. Following, it attempts to transform these materials into elements of architecture, as the functional components of a building. Forms derive their unique qualities from these materials; qualities that enrich our consciousness, evoke sensible memories, and fulfill expectations. Chosen for their qualities as well as their perceptions, brick and wood, present a dynamic dialogue about mass in volume.The story of this house is told in relation to how the brick responds to the primary structure and how it orchestrates architectural elements within the whole. The dichotomy between these two materials lends this study to a larger exploration of joinery. The internal joining of wood to wood, or tectonic joining, produces a different expression than the joining of different materials. Wood to brick, for instance produces the legible differentiation of the architectural elements within the house. The arrangement of these materials articulates structure as well as spatial distinctions within the whole. Where volumes detach, glass bridges these materials as its attributes blend the differentiation between an interior and exterior condition. Articulating how these materials meet addresses essential architectural questions of knowledge, thought, and order as well as ephemeral pleasures. To enjoy the physical experience, as it is embraced by all of the senses, is the final goal and desire of this thesis. / Master of Architecture / This quest began by trying to treat one side of a constructed line independently from the other side. Formal distinctions were made, and then later material distinctions in order to treat a building's interior and exterior independently. This thesis study treats the structure independently from the envelope, while creating spatial distinctions within the house through material decisions. Brick and wood were chosen for their contrasting properties, both physically and perceptually. The Brick, with its telluric, of the earth presence, has an obligation to the site, weather, and time. The wood on the other hand, with its tectonic nature, has an obligation to the human touch. The structure, which serves as protection from the elements, its pulled inside to live with the humans as heavy timber posts. The brick is then left to the essential elements of the house, to one day stand as ruins. Namely, the entrance, the hearth, the base, and parts of the envelope, The architectural questions are then asked through material composition and elemental joints.

Implied spatial boundaries are examined and evaluated at a camping shelter complex on an Eastern California lake. A grid of concrete columns house a series of suspended wooden boxes and a connecting ramp. / Master of Architecture

Yes / The biographical approach has become a well-recognized and adopted method to theorize the establishment and development of settlements in accord with their human occupation. Recent proposals for such a biographical model for the lake-dwellings of the northern Alpine region have been largely based upon theoretical and hypothetical considerations. Lake-dwelling sites in the Alpine region generally have excellent levels of organic preservation, particularly for artefacts and building foundations, but with poor representation of building superstructures. They do however have high potential for archaeology micromorphological soil analysis, with sediment deposits providing indications of both human activity and environmental conditions within the settlement. Using specific examples from Switzerland, this paper intends to highlight some of the contributions that micromorphology can provide to the consideration of settlement biographies. / Swiss National Science Foundation