Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Plant Sciences (6)
- Ecology and Evolutionary Biology (5)
- Biology (4)
- Forest Biology (2)
- Forest Sciences (2)
-
- Other Plant Sciences (2)
- Plant Biology (2)
- Terrestrial and Aquatic Ecology (2)
- Biochemistry (1)
- Biochemistry, Biophysics, and Structural Biology (1)
- Botany (1)
- Environmental Indicators and Impact Assessment (1)
- Environmental Monitoring (1)
- Environmental Sciences (1)
- Genetics and Genomics (1)
- Other Ecology and Evolutionary Biology (1)
- Physical Sciences and Mathematics (1)
- Physiology (1)
- Institution
Articles 1 - 8 of 8
Full-Text Articles in Life Sciences
Climate Interactions Drive Tree Physiology And Growth In A Northeastern Forest Ecotone, Alexandra M. Barry
Climate Interactions Drive Tree Physiology And Growth In A Northeastern Forest Ecotone, Alexandra M. Barry
Electronic Theses and Dissertations
Climate change is a threat to global forest ecosystems. In the northeastern United States, forest trees are facing rising temperatures and increasingly inconsistent moisture regimes. In addition to long-term changes in climate conditions, there is concern about the potential for more frequent and intense climate extremes, which can have severe and rapid negative effects on tree physiology and growth. Further, climate extremes may co-occur to produce a greater magnitude of effect than the sum of their parts, with a prominent example being hot droughts, which are increasing in occurrence and severity. The impact of these and other extreme climate interactions …
Assessing Short-Term Microalgal Community Responses Over Altering Hydrological Conditions In Experimental Wetlands Of Costal Georgia, Maggie M. Kuhn
Assessing Short-Term Microalgal Community Responses Over Altering Hydrological Conditions In Experimental Wetlands Of Costal Georgia, Maggie M. Kuhn
Electronic Theses and Dissertations
Wetlands provide valuable ecosystem services such as nutrient cycling and carbon storage. Microalgae (i.e., diatoms) provide the foundation of primary production and determine rates of energy transfer throughout the system. Climate change models predict an increase in frequency of intense storms and severe drought conditions that pose a threat to known hydrological regimes and wetland ecosystem stability. The purpose of my study was to assess the effects of water permanence (i.e., duration of flooding) on diatom community structure in experimental wetlands. I predicted that wetlands with prolonged periods of flooding (i.e., permanent) would harbor a consistent diatom community throughout flooding …
Aboveground-Belowground Interactions: Roles Of Soil Biotic And Abiotic Factors On Switchgrass's (Panicum Virgatum) Growth, Defense Against Herbivory And Cell Wall Chemistry., Binod Basyal
Electronic Theses and Dissertations
Plants constantly interact with their biotic and abiotic soil environments. Most terrestrial plants form beneficial associations with soil microbes such as arbuscular mycorrhizal (AM) fungi, which are widely known for their ability to transfer soil phosphorus and nitrogen to the host plants. They help plants tolerate drought stress and improve plant defense against herbivores such as plant-parasitic nematodes (PPNs). This dissertation investigates the role of AM fungi on switchgrass’s (Panicum virgatum) growth, cell wall chemistry, and defense against PPNs using a combination of growth chamber and field studies. Switchgrass is a native warm-season species which is gaining traction as candidate …
Subalpine Forest Tree Seedling Response To Drought, Alex Goke
Subalpine Forest Tree Seedling Response To Drought, Alex Goke
Electronic Theses and Dissertations
Knowledge of tree species’ ability to tolerate drought is necessary to anticipate future forest dynamics with climate change, especially at the seedling stage given their role in shaping forest structure. We used precipitation reduction shelters to mimic drought for subalpine conifer seedlings (A. lasiocarpa and P. engelmannii) in the Rocky Mountains and compared survivorship and morphological and physiological responses to assess relative degrees of drought tolerance. We detected no significant investment in morphological tolerance traits (e.g. root biomass, leaf:stem area ratio) but substantial reductions in net photosynthesis. While shading partially ameliorated drought effects when precipitation reduction was moderate, …
Stoichiometric Homeostasis In Two Native And Two Invasive South Dakotan Grasses, Joshua Thonas Harvey
Stoichiometric Homeostasis In Two Native And Two Invasive South Dakotan Grasses, Joshua Thonas Harvey
Electronic Theses and Dissertations
Increased nutrient availability has been widely linked to the success of invasive plants, however a general mechanism explaining these observations is lacking. Stoichiometric homeostasis (H), which is the regulation of internal nutrient concentrations, has been used to explain changes in plant community diversity under alterations in nutrient availability. One hypothesis holds that plants with high regulation (larger H) decrease in abundance in nutrient enriched conditions but are stable in nutrient deficient and drought conditions, likely due to extensive root systems. Additionally, plants with low regulation (lower H) increase in abundance under nutrient enriched conditions but are sensitive to drought …
Wetland Biogeochemical Responses To Predicted Climate Change Scenarios, Angela R. Shaffer
Wetland Biogeochemical Responses To Predicted Climate Change Scenarios, Angela R. Shaffer
Electronic Theses and Dissertations
Wetlands are one of the world's largest known carbon sinks while comprising only a small amount of the Earth's surface. However, the amount of carbon sequestered by wetlands is shrinking as droughts and human disturbance increases. Carbon in wetlands is stored through the contrast of decomposition and sedimentation of organic matter and absorption of CO2 from the atmosphere by soil microbes. Understanding how changing hydrological regimes and increased wildfires will affect wetland soil and microbial processes is important in the face of predicted climate change for future wetland conservation practices. Specifically, I seek to understand the response of southeastern …
Quantifying Genetic Responses Of Plants To Drought Stress With A Comparative Transcriptome Approach, Jessica K. Devitt
Quantifying Genetic Responses Of Plants To Drought Stress With A Comparative Transcriptome Approach, Jessica K. Devitt
Electronic Theses and Dissertations
Mentzelia section Bartonia (Loasaceae) commonly occurs in some of the hottest and driest places in North America, but we poorly understand the mechanisms that allow them to tolerate such extreme environments. Morphological and physiological adaptations are well studied in model organisms. The underlying genetic responses to drought stress in non-model organisms like Mentzelia is unknown. To better understand and identify differences and similarities in genetic responses to drought stress between species existing in different habitats with differing water availability, three species from the genus Mentzelia were compared. Species of section Bartonia occur across an environmental gradient, from temperate to arid …
A Study Of Salmonid Growth In Two Southern Appalachian Headwater Streams, Joshua Argo
A Study Of Salmonid Growth In Two Southern Appalachian Headwater Streams, Joshua Argo
Electronic Theses and Dissertations
This study sampled salmonid populations in two headwater streams in East Tennessee, Briar Creek and Left Prong Hampton Creek. Length and weight data were used to calculate the growth of these populations to determine if significant variation exists between isolated brook trout populations. Slope comparisons concluded that there was a difference in growth between brook trout populations of these streams (p