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Anthropogenic Impacts To Essential Habitats In The Gulf Of Maine: A Case Study Of The American Lobster, Homarus Americanus, And Its Fishery, Andrew Goode
Electronic Theses and Dissertations
The Gulf of Maine has been fundamentally altered by anthropogenic forcings for decades and offers an ideal study system to monitor response to change. Through complex interactions between ocean warming, altered demographic bottlenecks, and reduced top-down controls, the American lobster (Homarus americanus Milne Edwards) capitalized on favorable conditions and proliferated within the Gulf of Maine. These changes catalyzed the expansion of the lobster fishery, elevated its status as North America’s most valuable marine resource, and shifted coastal communities towards a virtual lobster monoculture. The same processes that facilitated lobster to capitalize on favorable conditions may come with unintended consequences …
Biotic Interactions At Species’ Range Limits In A Changing Climate, Isaac Shepard
Biotic Interactions At Species’ Range Limits In A Changing Climate, Isaac Shepard
Electronic Theses and Dissertations
As the global climate changes, many species are shifting their geographic ranges, often towards the poles or upslope in elevation. The ubiquity of these observation has renewed discussions about the mechanisms that determine species’ range margins. Leading hypotheses state abiotic variables should be the most important factor for setting range limits in environmentally stressful habitats. However, I propose an alternative hypothesis that biotic interactions may still be critically important for setting range limits, even in abiotically stressful habitats. Using a model system of ponds in the Rocky Mountains of Colorado, I developed several field experiments to empirically test the role …
Forest Disturbance And Occupancy Patterns Of Carnivores: Results Of A Large-Scale Field Study In Maine, Usa, Bryn E. Evans
Forest Disturbance And Occupancy Patterns Of Carnivores: Results Of A Large-Scale Field Study In Maine, Usa, Bryn E. Evans
Electronic Theses and Dissertations
Understanding trends in the abundance and distribution of carnivores is important at global, regional and local scales due to their ecological role, their aesthetic and economic value, and the numerous threats to their populations. Carnivores in Maine range from the American black bear (Ursus americanus), to numerous native mesocarnivore species, such as American marten (Martes americana), fisher (Pekania pennanti), coyote (Canis latrans), red fox (Vulpes vulpes), bobcat (Lynx rufus), Canada lynx (Lynx canadensis) and to two small weasel species (Mustela erminea and Neogale frenata). …
Experimental Warming Effects On Growth, Yield, And Biotic Pressure Of Wild Blueberries In Maine, Yu-Ying Chen
Experimental Warming Effects On Growth, Yield, And Biotic Pressure Of Wild Blueberries In Maine, Yu-Ying Chen
Electronic Theses and Dissertations
As the global temperature rises, a need exists for understanding the potential impacts of warming on the wild blueberry industry in Maine. Warming can change the physiology, growth, and pest pressure of crops, and also accelerates the evapotranspiration rate, resulting in decreased soil moisture. The objectives of this study were: (1) To characterize the response of phenological, morphological, and physiological traits of the wild blueberries to warming; (2) To quantify the impacts of different temperature levels on yield and berry quality; (3) To determine the abiotic and biotic factors that may influence yield, such as winter damages, freezing temperatures, the …
To Know The Land With Hands And Minds: Negotiating Agricultural Knowledge In Late-Nineteenth-Century New England And Westphalia, Justus Hillebrand
To Know The Land With Hands And Minds: Negotiating Agricultural Knowledge In Late-Nineteenth-Century New England And Westphalia, Justus Hillebrand
Electronic Theses and Dissertations
Ever since the eighteenth century, experts have tried to tell farmers how to farm. The agricultural enlightenment in Europe marked the beginning of a long arc of new experts aiming to change agricultural knowledge and practice. This dissertation analyzes the pivotal period in the late nineteenth and early twentieth century in Germany and the United States when scientists, improvers, and market agents began to develop comprehensive ways to communicate agricultural innovation to farmers. In a functional approach to analyzing the negotiation of agricultural knowledge through its communication in things, words, and practices, this dissertation argues that the process of change …
Discards & Diverse Economies: Reuse In Rural Maine, Brieanne Berry
Discards & Diverse Economies: Reuse In Rural Maine, Brieanne Berry
Electronic Theses and Dissertations
This dissertation presents an ethnographic exploration of diverse reuse economies in rural Maine in an effort to illuminate both how used goods move between people and organizations, as well as the value of that movement for people and communities. In response to a growing number of calls for research into the social dimensions of circular economies, this research explores the varied and uneven impacts of materials reuse as they are experienced by local participants. This work uses a qualitative approach, drawing on two main methods: participant observation in reuse establishments and in-depth, semi-structured interviews with reuse participants. This rich qualitative …
Development Of Nanostructured Titania-Incorporated Photocatalysts For Environmental Applications, Sudheera B. Yaparatne
Development Of Nanostructured Titania-Incorporated Photocatalysts For Environmental Applications, Sudheera B. Yaparatne
Electronic Theses and Dissertations
Ultraviolet (UV) radiation application in water and wastewater treatment has become a common approach for inactivation of protozoa and other pathogenic microorganisms. However, degradation of most organic compounds, such as taste and odor products prevalent in surface waters, has not been proven effective with direct UV photolysis. Advanced oxidation processes (AOPs) that involve efficient photocatalysts like TiO2 show an advantage over direct UV photolysis providing fast reaction rates and non-selective oxidation of contaminants. However, the real-world application of TiO2 in water and wastewater treatment is limited due to difficulties in separating the suspended nanosized particles following treatment, the …
Evaluating Methods For Research In Physical Weed Control And Farm Asset Tracking, Johnny J. Sanchez
Evaluating Methods For Research In Physical Weed Control And Farm Asset Tracking, Johnny J. Sanchez
Electronic Theses and Dissertations
Effective weed control has long been recognized as critical for agricultural production, yet weeds remain a major constraint to production and economic return in many agroecosystems. Moreover, improvements in physical weed control are necessary to address increasing problems of herbicide resistance in weeds of grain and fiber crops and the high cost of hand weeding in vegetables. From tractor-mounted cultivation tools to autonomous weeders, weeding implements are affected by weeds, crops, soil conditions, and actuator effectiveness. In order to address these complex and often interacting factors concerning weed control, new and innovative tools must be designed and evaluated. Chapter one …