Ecology and Evolutionary Biology Commons^™

A Tragedy Exposed? Clear Growth Medium Reveals Competing Roots, Christopher H. Karounos, Deric Miller, Philip Crowley, Nicholas Mcletchie

Kaleidoscope

Abstract

Tragedy of the Commons (ToC) is the exploitation of an open-access resource that is exploited by selfish individuals to the detriment of all. Examples include open sea fisheries, cattle grazing, pollution, deforestation and plants competing over shared soil nutrients and space. Tragically, these resources become depleted and plants become severely resource limited. Our study seeks to determine if a ToC causes two plants sharing resources to reproduce less successfully than two plants owning the equivalent amount of personal resources. We predict that plant root competition creates a ToC by increasing root mass while reducing reproductive mass. Our study uses …

Identifying Sources Of The Tragedy Of The Commons In Root Competition: A Spatially Explicit Simulation Model And Plants Grown In Transparent Growth Medium, R Deric Leith Miller

Theses and Dissertations--Biology

Existing research shows that plants produce less root when growing alone than when growing in competition with other plants. When plants under root competition over-allocate resources to roots at the cost of reproduction, it represents a Tragedy of the Commons. I constructed simulation models to determine the circumstances likely to give rise to a Tragedy of the Commons, and explore mechanisms by which plants may solve it. I grew plants in nutrient-rich transparent gel, allowing me to quantify root growth and development without destructive sampling. My plants responded positively to additional space and the presence of a competitor at full …

Grassland Sustainability In Kentucky: Case Studies Quantifying The Effects Of Climate Change On Slug Herbivory In Pastures And Different Home Lawn Systems On Turf Greenhouse Gas Emissions, Daniel Adam Weber

Theses and Dissertations--Plant and Soil Sciences

Grasslands comprise the greatest biome by land area, are sensitive to environmental factors affected by climate change, and can impact future climate change through their ability to store and release greenhouse gasses (GHGs). I performed two studies: 1) evaluated the effects of increased temperature and precipitation on slug herbivory/abundance and pasture forage production; 2) quantified different homeowner lawn system effects on soil-to-atmosphere GHG emissions. Climate change will likely affect pasture forage production, with implications for slug herbivory and abundance. I found little evidence that slugs have or will have significant effects on pasture production or plant community. Warming altered the …

A Plant Trait-Based Approach To Evaluate The Ability Of Native C3 And C4 Grasses To Restore Functionality To A Remnant Bluegrass Savanna-Woodland In Kentucky, Usa., Jann E. Fry

Theses and Dissertations--Biology

Temperate Midwestern oak savannas are considered imperiled ecosystems with < 1 % remaining since the time of European settlement and are identified as critical areas for preservation. Restoration of Midwestern oak savannas is challenging due to the lack of accurate historical data, few intact remnants remaining to study, and lack of restoration ecology studies. A plant trait-based approach was used to evaluate the ability of six C₃ and three C₄ native bunchgrasses to restore functionality to a remnant savanna–woodland of the Bluegrass Region of Kentucky. The response and effect framework was used to assess the response of the nine native grasses according to the habitat filters of interannual precipitation, inter- vs. intra-specific competition, and simulated grazing. The effect traits associated with plant-soil nitrogen and carbon cycling were also assessed. The response traits of interannual competition and inter- vs. intra-specific competition along with the effect traits plant-soil nitrogen and carbon cycling were measured in a monoculture experiment …

Exploring The Links Between Seasonal Variation And Spider Foraging, Thomas Edward Dantas Whitney

Theses and Dissertations--Entomology

According to optimal foraging theory, generalist predators, such as spiders, are thought to feed indiscriminately on prey according to its availability, especially when food is scarce. In contrast, generalists can display selective feeding decisions under regimes of high prey abundance, but few studies have tracked changes in prey choice on a seasonal basis under open field conditions. Additionally, adaptations to surviving winter have been largely ignored in the research of foraging behavior. To elucidate this, I monitored prey availability and collected common forest-dwelling wolf spiders for molecular gut-content analysis, in parallel for 18 months, to assess the temporal changes occurring …