Open Access. Powered by Scholars. Published by Universities.®
- Keyword
Articles 1 - 5 of 5
Full-Text Articles in Life Sciences
Effects Of Temperature And Pollinator Availability On Plant Reproductive Success In The Indiana Spring Ephemeral Community, Asya Robertshaw
Effects Of Temperature And Pollinator Availability On Plant Reproductive Success In The Indiana Spring Ephemeral Community, Asya Robertshaw
Open Access Dissertations
Temperature is a key driver of phenology in both plants and insects, and even small changes in temperature can impact the reproductive success of insect-pollinated plants by influencing access to pollinator services. While it is well-established that temperature variation directly impacts the flowering phenology of many plant species, the mechanisms by which it ultimately influences seed production via the pollinator community are not well understood. Climate change has the potential to disrupt the temporal synchrony between plants and their primary pollinators, especially if the two rely on different seasonal cues for the timing of their life history events. If the …
Undercover Predators: Vegetation Mediates Foraging, Trophic Cascades, And Biological Control By Omnivorous Weed Seed Predators, Carmen K Blubaugh
Undercover Predators: Vegetation Mediates Foraging, Trophic Cascades, And Biological Control By Omnivorous Weed Seed Predators, Carmen K Blubaugh
Open Access Dissertations
Weed pressure is the most costly challenge that vegetable growers face, requiring more labor investment than other production inputs. Vertebrate and invertebrate seed predators destroy a large percentage of weed propagules on the soil surface, and their ecosystem services may ease labor requirements for farmers in herbicide-free systems. Cover provided by living vegetation is an important predictor of seed predator activity, and my dissertation takes a comprehensive approach to understanding the behavior, predator, and environment-mediated mechanisms by which cover impacts weed seed predation in crop environments. ^ First, I performed a meta-analysis of 27 studies to quantitatively evaluate what is …
Consequences Of Short-Term Water Temperature Variability To Fish: Current And Future Climate Change Impacts, David P. Coulter
Consequences Of Short-Term Water Temperature Variability To Fish: Current And Future Climate Change Impacts, David P. Coulter
Open Access Dissertations
Water temperature has a profound influence on aquatic ectotherms by affecting all aspects of biological organization; from chemical and molecular functioning to whole-organism and population-level impacts. Natural processes and anthropogenic activities can create conditions where temperatures vary greatly through space and time. While exposure to temperature changes lasting ≥ 24 hours have been examined in some species, it is unclear how more rapid (< 24 hours; sub-daily) thermal fluctuations affect aquatic ectotherms. I used a combination of field observations, laboratory experiments, and modeling simulations to understand: 1) how habitat quality of aquatic ectotherms is affected in thermally dynamic environments; 2) the role of sub-daily temperature fluctuations on growth, survival, and stress responses in juvenile and adult fish; 3) how fish early life stages are affected by sub-daily temperature fluctuations; and 4) what impact thermally dynamic environments have on a model species at a population-level. A model quantifying habitat quality around power plant thermal discharges indicated that elevated and variable discharge temperatures affected habitat quality over a relatively small spatial area for aquatic ectotherms. Models examining elevated temperatures representing climate warming showed that the effects of industrial discharges and climate warming could have an interactive effect on habitat quality by increasing the spatial area and duration over which industrial thermal effluents impact aquatic ectotherms. Laboratory experiments indicated that closely related fishes can respond differently to the same sub-daily temperature fluctuations. Yellow perch (Perca flavescens) had higher consumption and growth under sub-daily temperature fluctuations but developed skin lesions; an indication of thermal stress. In contrast, these same fluctuations reduced growth in physiologically similar walleye (Sander vitreus) …
Carrion-Associated Arthropods In Rural And Urban Environments, Serena Daye Gross
Carrion-Associated Arthropods In Rural And Urban Environments, Serena Daye Gross
Open Access Dissertations
Preferences of arthropods are important in forensic entomology, as the species collected can help determine the postmortem interval or if remains have been moved. This study looked at arthropods that are attracted to pig carcasses in rural and urban habitats in Northwest Indiana. The species and number of carrion-associated arthropods that are found at a carcass vary with habitat type, month, and stage of decomposition. Lucilia sericata (Diptera: Calliphoridae) is a synanthropic species that was found in higher numbers in urban locations for both adults and larvae. Though L. sericata had higher numbers in urban habitats, caution must be exercised …
Biology And Ecology Of Bigheaded Carp In An Invaded Ecosystem, Alison Adele Coulter
Biology And Ecology Of Bigheaded Carp In An Invaded Ecosystem, Alison Adele Coulter
Open Access Dissertations
Globally, the homogenization of species has become a threat to biodiversity. As species are transported around the world, a portion of these species, released intentionally or accidentally, may become invasive and can produce negative impacts. Great effort has been invested into early identification and prevention of invasions as these are considered less expensive than managing an invasion. Unfortunately, species may exhibit varying characteristics across ecosystems, and so their behavior and potential survival in a new environment may be difficult to predict. Therefore, I examined trends in the biology and behavior of invasive fishes, including the plasticity surrounding these and how …