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Full-Text Articles in Life Sciences
How Aquatic Insects Mitigate Temperature-Oxygen Challenges Via Behavioral, Morphological, And Physiological Plasticity, Jackson H. Birrell
How Aquatic Insects Mitigate Temperature-Oxygen Challenges Via Behavioral, Morphological, And Physiological Plasticity, Jackson H. Birrell
Graduate Student Theses, Dissertations, & Professional Papers
How do organisms respond to environmental challenges and to environmental change? These questions occupy a central place in ecology and answering them will help us to understand why species live where they do, how organisms are affected by human activities, and, ultimately, how to choose among alternative conservation strategies. These questions are difficult, however, for two reasons. First, environmental challenges often involve multiple, interacting stressors. Second, individual responses can be modified by behavioral, morphological, and physiological plasticity. My dissertation investigates how interactions between temperature and oxygen influence the performance and survival of aquatic insects and how plasticity allows individuals to …
An Evaluation Of Landscape, Climate, And Management Impacts On Bumble Bees (Hymenoptera: Apidae: Bombus) In Agroecosystems, Morgan Elizabeth Christman
An Evaluation Of Landscape, Climate, And Management Impacts On Bumble Bees (Hymenoptera: Apidae: Bombus) In Agroecosystems, Morgan Elizabeth Christman
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Bumble bees play pivotal roles in pollinating wild and cultivated plant communities. Unfortunately, bumble bee populations are declining due to disturbances such as landscape conversion and climate change. Additionally, traps used to monitor pest insect populations often capture bumble bees, leading to a concern that trap captures increase bumble bee mortality. First, I studied bumble bee communities based on land cover and weather variables in agricultural fields in Utah. Bumble bee communities were more diverse in agricultural fields with more agricultural land in the surrounding area, low temperatures, and high humidity during the growing season, and less diverse in fields …
From Individuals To Communities: The Effect Of Climate Change On Ectothermic Predators, Matthew Lawrence Meehan
From Individuals To Communities: The Effect Of Climate Change On Ectothermic Predators, Matthew Lawrence Meehan
Electronic Thesis and Dissertation Repository
The living components of ecological systems exist within a nested hierarchy, consisting of individuals, populations, and communities. Because of this nestedness, climate change can greatly impact ecological systems, as whole-organism metabolic and physiological demands change for ectotherms under warming, the effects of which may compound with every succeeding level. Therefore, a multi-level approach can better isolate how climate change will reshape ecological systems. In my doctoral research, I used feeding and mesocosm experiments to examine how climate change affects ectothermic predators at the individual-, population-, and community-level, using mesostigmatic mites (Arachnida: Parasitiformes) as my model predator. My research objectives were …
Investigating The Effect Of A Facultative Symbiont, Hamiltonella Defensa, On Pea Aphid, Acyrthosiphon Pisum, Fecundity And Behavior In Elevated Co₂ Atmospheres, Tyler J. Follman
Investigating The Effect Of A Facultative Symbiont, Hamiltonella Defensa, On Pea Aphid, Acyrthosiphon Pisum, Fecundity And Behavior In Elevated Co₂ Atmospheres, Tyler J. Follman
Electronic Theses and Dissertations
As atmospheric carbon dioxide (CO2) levels continue to rise, it is important to study how economically important organisms, like the pea aphid, Acyrthosiphon pisum, will react to these conditions. The pea aphid feeds on the phloem of crop plants like alfalfa, peas, and fava beans, where it not only directly harms the plant but also can spread plant viruses. A wide variety of factors can influence pea aphid fecundity and behavior. Some of these factors are abiotic, like atmospheric conditions, and some are biotic, like microorganisms with which the pea aphid has a mutualistic relationship. In this thesis, …
Adaptation Strategies For Wild Blueberry Growers In A Changing Climate: Mulching Effects On Crop Productivity And Fertility Effects On Blueberry Gall Midge, Rebecca Gumbrewicz
Adaptation Strategies For Wild Blueberry Growers In A Changing Climate: Mulching Effects On Crop Productivity And Fertility Effects On Blueberry Gall Midge, Rebecca Gumbrewicz
Electronic Theses and Dissertations
Wild blueberry (Vaccinium angustifolium Aiton.) cropping systems are considered resilient to environmental changes due to ecological and genetic diversity within each field. However, wild blueberries can be sensitive to weather fluctuations that cause extreme temperature or moisture regimes. Climate change in Maine is represented by increasing rates of warming temperatures, more intense precipitation events, and more frequent atmospheric “blocking” patterns. Warming temperatures result in the northward expansion of pest ranges and altered growing seasons. More extreme rainfall events lead to damaged plantings and soil erosion. Atmospheric blocking leads to an increased likelihood of heat waves and drought. Two experiments were …
Diversity And Drivers Of Oribatid Mites (Acari: Oribatida) In Boreal Peatlands, Carlos Rafael De Araujo Barreto
Diversity And Drivers Of Oribatid Mites (Acari: Oribatida) In Boreal Peatlands, Carlos Rafael De Araujo Barreto
Electronic Thesis and Dissertation Repository
Boreal peatlands are important ecosystems for carbon cycling, storing 1/3 of the world’s terrestrial carbon in only ~3% of the globe, making them a key component of potential mitigation strategies in response to global climate warming. Experiments have shown that warming can affect plant and microbial communities in ways that potentially shift peatlands from carbon sinks to sources. Soil food webs, including the microarthropod community, are key in carbon cycling but are relatively understudied both in peatlands and under experimental warming. My research capitalized on a large-scale experimental field manipulation of warming in two contrasting peatland sites in Northern Ontario, …
Macroinvertebrate Responses To Hydrological Variation In Experimental Wetlands., Sergio A. Sabat-Bonilla
Macroinvertebrate Responses To Hydrological Variation In Experimental Wetlands., Sergio A. Sabat-Bonilla
Electronic Theses and Dissertations
Predicted increases in the frequency of intense storms and periods of severe drought due to climate change represent a threat to wetland macroinvertebrate communities through alterations to the hydrological regime. I used experimental ponds to assess the effects of water permanence (i.e., duration of flooding) on the communities of aquatic macroinvertebrates. I predicted that permanent ponds would harbor higher diversity of longer-lived taxa whereas temporary ones will favor colonization by quick turnover, short-lived taxa and support lower consumer diversity. Results show differences in macroinvertebrate communities between permanent and temporary ponds can be mostly explained by hydrology and the amount of …
Physiological Ecology Of Overwintering And Cold-Adapted Arthropods, Leslie Jean Potts
Physiological Ecology Of Overwintering And Cold-Adapted Arthropods, Leslie Jean Potts
Theses and Dissertations--Entomology
Given their abundance and diversity, arthropods are an excellent system to investigate biological responses to winter. Winter conditions are being majorly impacted by climate change, and therefore understanding the overwintering biology of arthropods is critical for predicting ecological responses to climate change. In Chapters 2 and 3, I investigate the winter biology of a winter-active wolf spider. I show that winter-active spiders can take advantage of periodic prey resources and grown in the winter, which may allow them to get a jumpstart on spring reproduction. I also investigate spiders’ ability to track changes in their environment by quantifying low temperature …
Heat For The Masses: Thermal Ecology Of The Western Tent Caterpillar, Victoria Dahlhoff
Heat For The Masses: Thermal Ecology Of The Western Tent Caterpillar, Victoria Dahlhoff
Graduate Student Theses, Dissertations, & Professional Papers
A unique feature of some gregarious, colonial insects is their ability to create external structures that alter environmental conditions for the entire (often family) group. A combination of physical alteration of local microhabitats and behavioral thermoregulation allows many of these animals to actively control their body temperatures, which allows them to regulate energy use and metabolism in variable thermal environments. Here I describe mechanisms of microhabitat modification and thermal regulation in the western tent caterpillar, Malacosoma californicum pluviale. Tent caterpillars build communal silk tents, whose temperatures can rise substantially above ambient air temperature. I experimentally manipulated colony sizes and examined …
Blacklegged Tick (Ixodes Scapularis) Distribution In Maine, Usa, As Related To Climate Change, White-Tailed Deer, And The Landscape, Susan P. Elias
Blacklegged Tick (Ixodes Scapularis) Distribution In Maine, Usa, As Related To Climate Change, White-Tailed Deer, And The Landscape, Susan P. Elias
Electronic Theses and Dissertations
Lyme disease is caused by the bacterial spirochete Borrelia burgdorferi, which is transmitted through the bite of an infected blacklegged (deer) tick (Ixodes scapularis). Geographic invasion of I. scapularis in North America has been attributed to causes including 20th century reforestation and suburbanization, burgeoning populations of the white-tailed deer (Odocoileus virginianus) which is the primary reproductive host of I. scapularis, tick-associated non-native plant invasions, and climate change. Maine, USA, is a high Lyme disease incidence state, with a history of increasing I. scapularis abundance and northward range expansion. This thesis addresses the question: “To …
Biogeography Of Endemic Dragonflies Of The Ozark-Ouachita Interior Highlands, Wade Alexander Boys
Biogeography Of Endemic Dragonflies Of The Ozark-Ouachita Interior Highlands, Wade Alexander Boys
Graduate Theses and Dissertations
A common pattern across many taxonomic groups is that relatively few species are widespread while the majority are restricted in their geographic ranges. Such species distributions are used to inform conservation status, which poses unique challenges for rare or cryptic species. Further, priority status is often designated within geopolitical boundaries, which may include only a portion of a species range. This, coupled with lack of distributional data, has resulted in species being designated as apparently rare throughout some portions of their range, which may not accurately reflect their overall conservation need. The Interior Highlands region of the central United States …
A Comparison Of Benthic Macroinvertebrate Assemblages Between Perennial And Intermittent Headwater Streams Of The Mattole River In Northern California, Usa, Mason S. London
Cal Poly Humboldt theses and projects
Intermittent streams are common throughout the world and comprise 60% or more of total river lengths in the conterminous United States. Despite their prevalence, intermittent streams are understudied, particularly first-order headwater streams, which are vital for maintaining the function, health and biotic diversity of river networks. In June 2016, I sampled five intermittent and five perennial headwater streams in the Mattole River watershed in northwestern coastal California, USA, to compare benthic macroinvertebrate (BMI) assemblages between intermittent and perennial streams. BMI samples were collected using a 500µm mesh D-net at eight randomly located riffles along a 150-m reach, and then composited, …
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 …
Ant Community Dynamics And The Effects Of Global Warming, Katharine Lisa Stuble
Ant Community Dynamics And The Effects Of Global Warming, Katharine Lisa Stuble
Doctoral Dissertations
This dissertation seeks to provide an understanding of how species coexist and, further, how climate change may alter communities by acting on the mechanisms that promote coexistence. Specifically, I examined coexistence among ant species in eastern deciduous forests and the effects that warming may have on foraging activity. Through a series of field observations, I sought evidence for the importance of four of the most commonly cited mechanisms for coexistence among ant species: the dominance – discovery tradeoff, the dominance – thermal tolerance tradeoff, spatial segregation, and niche partitioning. In this system, I did not find evidence for any of …