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- Climate change (7)
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- Atlantic salmon (2)
- Carbon cycling (2)
- Carbon dioxide (2)
- Community ecology (2)
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- Mercury (2)
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- Urea (2)
- 15N (1)
- Aboveground-belowground linkages (1)
- Acari (1)
- Acidification (1)
- Agricultural drainage (1)
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- Atmospheric deposition (1)
- Bank Swallows (1)
- Bat habitat use (1)
- Behavioural Partitioning (1)
Articles 1 - 30 of 36
Full-Text Articles in Life Sciences
Short-Term Versus Long-Term Effects Of Nitrogen Addition And Warming On Ecosystem N Dynamics In A Grass-Dominated Temperate Old Field, Benjamin F. A. Souriol
Short-Term Versus Long-Term Effects Of Nitrogen Addition And Warming On Ecosystem N Dynamics In A Grass-Dominated Temperate Old Field, Benjamin F. A. Souriol
Electronic Thesis and Dissertation Repository
Increased atmospheric nitrogen (N) deposition and climate warming are both anticipated to influence the ecosystem N dynamics of northern temperate ecosystems substantially over the next century. Nevertheless, in field experiments with N addition and warming treatments, temporal scale can play an important role in determining the extent of treatment effects on N dynamics, and it is unclear to what extent the results of short-term studies can be extrapolated to responses over longer time scales. I compared the short-term versus long-term effects of N addition and warming on net N mineralization, N leaching, and N retention in a grass-dominated old field. …
The Detectability Of Atlantic Salmon (Salmo Salar) Microsatellite And Mitochondrial Environmental Dna, Simone N. Miklosi
The Detectability Of Atlantic Salmon (Salmo Salar) Microsatellite And Mitochondrial Environmental Dna, Simone N. Miklosi
Electronic Thesis and Dissertation Repository
Little is known about what information can be gathered from microsatellite eDNA. It is important to gain a deeper understanding of the detectability and analysis of microsatellite eDNA because it could provide information about population size that mitochondrial eDNA cannot. Water samples were collected from tank and river experiments, and rivers known to contain Atlantic salmon (Salmo salar) and analyzed for Atlantic salmon mitochondrial and microsatellite eDNA. Mitochondrial eDNA was detected from all the tank experiments and 10 out of 15 rivers known to contain Atlantic salmon. Microsatellite eDNA was detected from all the tank experiments and none …
The Effect Of Dietary Thiaminase On Cardiac Function And Morphology In Lake Trout (Salvelinus Namaycush), Peter Baker
The Effect Of Dietary Thiaminase On Cardiac Function And Morphology In Lake Trout (Salvelinus Namaycush), Peter Baker
Electronic Thesis and Dissertation Repository
Thiamine deficiency from the consumption of invasive, high-thiaminase prey fishes is considered to be a major barrier for lake trout restoration in the Great Lakes. In fishes, an understudied aspect of thiamine deficiency is its effect on cardiac function. I examined the effects of dietary thiaminase on cardiac function and morphology in lake trout, specifically as they relate to thermal tolerance. Two hatchery strains of lake trout (Seneca and Slate) were raised on a control or thiaminase diet for nine months. The thiaminase diet was associated with significant ventricle enlargement, impaired cardiac function, and reduced thermal tolerance; these effects were …
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 …
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, …
An Investigation Of Epiphytic Diatom Substrate Specificity And Its Use In Paleolimnology, David Rawn Zilkey
An Investigation Of Epiphytic Diatom Substrate Specificity And Its Use In Paleolimnology, David Rawn Zilkey
Electronic Thesis and Dissertation Repository
Submerged macrophyte communities are an important component of lake ecosystems that can be altered by anthropogenic disturbances. In the absence of direct monitoring, it is difficult to know how these communities respond to such disturbance. This thesis investigated the potential of epiphytic diatoms preserved in lake sediments to record submerged macrophyte community composition. Epiphytic diatoms from Chara sp., Myriophyllum spicatum and Potamogeton robbinsii were sampled from Gilmour Bay, Ontario, Canada to assess whether submerged macrophyte species were characterized by distinct diatom communities. Principal components analysis indicated overlap, but analysis of similarity suggested there were differences in diatom community composition. A …
Amount And Sources Of Population Variability In The Metabolome Of A Crayfish Species, Cora Bilhorn
Amount And Sources Of Population Variability In The Metabolome Of A Crayfish Species, Cora Bilhorn
Electronic Thesis and Dissertation Repository
My study investigated the amount of variation associated with region and stream scales in the metabolomes of northern crayfish (Faxonius virilis), collected from seven streams distributed across three ecoregions in Western Canada. Additionally, my study measured metabolomes of crayfish from the same seven streams after experiencing a common laboratory environment to separate the effects of environmental and genetic variation. Region and stream scales were found to be poor predictors of metabolomic variation among crayfish sampled in the field but exhibited increased predictive ability among crayfish exposed to the common environment, indicating crayfish from separate populations responded differently to …
Effects Of Dietary Thiaminase On Reproductive Traits In Three Populations Of Atlantic Salmon Targeted For Reintroduction Into Lake Ontario, Kimberly T. Mitchell
Effects Of Dietary Thiaminase On Reproductive Traits In Three Populations Of Atlantic Salmon Targeted For Reintroduction Into Lake Ontario, Kimberly T. Mitchell
Electronic Thesis and Dissertation Repository
The fitness of reintroduced salmonids in Lake Ontario can be reduced by high levels of thiaminase in exotic prey consumed at the adult stage. If sensitivity to dietary thiaminase differs among the three Atlantic salmon populations targeted for reintroduction into Lake Ontario, this could significantly influence their performance. I quantified the effects of experimental diets that contained high or low (control) levels of thiaminase on thiamine concentrations, survival, growth rate, and reproductive traits (sperm and egg quality) in Atlantic salmon from the three candidate source populations. Fish that consumed the high-thiaminase diet had comparable growth rates, but lower survival and …
Diet Composition And Mercury Exposure In Bank Swallows (Riparia Riparia) Breeding At Lakeshore And Aggregate Pits, Corrine S. V. Génier
Diet Composition And Mercury Exposure In Bank Swallows (Riparia Riparia) Breeding At Lakeshore And Aggregate Pits, Corrine S. V. Génier
Electronic Thesis and Dissertation Repository
Bank Swallows (Riparia riparia), a threatened species in Ontario, breed primarily in banks at lakeshores and in artificial aggregate pits. Inland pits may be ecological traps for this species, but the relative tradeoffs between these two nesting habitats are unknown. Availability of aquatic emergent insects at lakeshores may have associated nutritional benefits (e.g. Omega-3 fatty acids) and contaminants (e.g. mercury) that can directly influence juvenile growth. This study compares these breeding habitats to evaluate dietary differences as revealed by fatty acids, stable isotopes (δ13C, δ15N, δ2H), fecal DNA barcoding, and mercury. Lakeshore-nesting …
The Stability Of Temperate Lakes Under The Changing Climate, Aleksey Paltsev
The Stability Of Temperate Lakes Under The Changing Climate, Aleksey Paltsev
Electronic Thesis and Dissertation Repository
There is a collective prediction among ecologists that climate change will enhance phytoplankton biomass in temperate lakes. Yet there is noteworthy variation in the structure and regulating functions of lakes to make this statement challengeable and, perhaps, inaccurate. To generate a common understanding on the trophic transition of lakes, I examined the interactive effects of climate change and landscape properties on phytoplankton biomass in 12,644 lakes located in relatively intact forested landscapes. Chlorophyll-a (Chl-a) concentration was used as a proxy for phytoplankton biomass. Chl-a concentration was obtained via analyzing Landsat satellite imagery data over a 28-year period (1984-2011) and using …
Above- And Belowground Community Linkages In Boreal Peatlands And Climate Warming Implications, Caitlyn Lyons
Above- And Belowground Community Linkages In Boreal Peatlands And Climate Warming Implications, Caitlyn Lyons
Electronic Thesis and Dissertation Repository
Aboveground plants provide resources to the belowground microbial community via plant litter and, in turn, the belowground microbial community provides nutrients for plant uptake, linking the two systems. My aim was to characterize and describe differences in plant community composition, plant litter quality and microbial community composition between two boreal peatlands in northern Ontario. These peatlands have contrasting plant and microbial communities, the Sphagnum moss-dominated peatland harboring a higher fungi to bacteria ratio compared to the Carex sedge-dominated peatland. Clear open top chambers were installed at both sites to simulate warming. Higher temperatures decreased Sphagnum moss in the Sphagnum-dominated …
Carbon Cycling In Northern Fen Peatlands – Implications For Climate-Driven Changes Of Ecosystem Carbon Fluxes, Jing Tian
Electronic Thesis and Dissertation Repository
Northern peatlands are important long-term carbon (C) sinks with one-third of northern hemisphere soil organic carbon being stored there. Cool and wet environments at higher latitudes promote C accumulation in northern peatlands by limiting the C loss from decomposition. Northern latitudes are anticipated to experience disproportionately faster climate warming in the future, putting the vast C stores in northern peatlands at risk. There is a concern that northern peatlands are becoming net C sources and further accelerate climate warming. Using both laboratory and field experiments, this doctoral research aimed to explore the potential response of C cycling in northern peatlands …
Patterns And Drivers Of Stream Benthic Macroinvertebrate Community Taxonomy And Function In Agroecosystems, Edward M. Krynak
Patterns And Drivers Of Stream Benthic Macroinvertebrate Community Taxonomy And Function In Agroecosystems, Edward M. Krynak
Electronic Thesis and Dissertation Repository
Anthropogenic activities continue to expand and intensify resulting in vast areas of the globe being dominated by human land uses. Effective land management and conservation decisions depend on our ability to understand and predict biological response to further disturbance in already stressed ecosystems. Moreover, insight into biological response to ecological stressors may be advanced by using trait and functional community measures in combination with taxonomy. My dissertation goal was to describe patterns and drivers of variation in benthic macroinvertebrate communities (BMIC) taxonomic composition and function in streams in an agriculturally dominated landscape. I achieved my goal by conducting three related …
Hierarchical Variation In Cellulose Decomposition Across Southern Ontario Reference Streams, Jenna R. Webb
Hierarchical Variation In Cellulose Decomposition Across Southern Ontario Reference Streams, Jenna R. Webb
Electronic Thesis and Dissertation Repository
The cotton strip assay (CSA) has been promoted as a method of incorporating functional indicators into standardized river assessments by study of organic-matter decomposition. However, operationalization of the CSA as an indicator requires testing the spatial and temporal controls of variance associated with decomposition of cotton strips at regional reference sites. I conducted a hierarchically structured study of decomposition rates in Ontario, Canada. Cotton strips were deployed during the spring, summer and fall in pool and riffle habitats of 22 streams located in three distinct physiographic regions. Partitioning of variation among hierarchical scales associated with rates of decomposition were examined …
Plant Stimuli-Responsive Biodegradable Polymers For The Use In Timed Release Fertilizer Coatings, Spencer Heuchan
Plant Stimuli-Responsive Biodegradable Polymers For The Use In Timed Release Fertilizer Coatings, Spencer Heuchan
Electronic Thesis and Dissertation Repository
The use of nitrogen-based fertilizers continues to accelerate with human population growth and increases in global food requirements. Enhanced efficiency fertilizers (EEFs) have been developed to improve the synchronization between nutrient supply and crop nutrient demand. However, many of the current controlled release fertilizers are coated with non-degradable polymers that contribute to accumulation of microplastics within ecosystems. This thesis describes research towards the development of a new class of fertilizer coatings using a self-immolative polymer known as poly (ethyl glyoxylate) (PEtG). PEtG itself does not have suitable properties to produce a viable coating but once blended with another degradable polyester …
Atmospheric Change Promotes Increasing Cyanobacteria Dominance In Swedish Lakes, Erika Christiane Freeman
Atmospheric Change Promotes Increasing Cyanobacteria Dominance In Swedish Lakes, Erika Christiane Freeman
Electronic Thesis and Dissertation Repository
The frequency and intensity of cyanobacteria blooms are increasing globally. The interacting effects of environmental drivers, including increased temperature, altered precipitation, reduced acidification-with associated shifts in nutrient limitation- and increased dissolved organic matter loads to lakes are predicted to create favourable environmental conditions for cyanobacteria in northern lakes. This prediction was tested in 28 nutrient-poor Swedish lakes over 16 years (1998-2013). Increases in cyanobacteria abundance were identified in 21% of the study sites, composed mostly of increases in three specific genera: Merismopedia, Chroococcus, and Dolichospermum. Increases in temperature favoured Merismopedia dominance in lakes with low pH and high nitrogen to …
Soil Homogenization: Plant Species Diversity, Ecosystem Properties And Soil Freezing Effects During Tallgrass Prairie Restoration, Holly J. Stover
Soil Homogenization: Plant Species Diversity, Ecosystem Properties And Soil Freezing Effects During Tallgrass Prairie Restoration, Holly J. Stover
Electronic Thesis and Dissertation Repository
Tillage can increase soil uniformity in former agricultural sites. Within plant communities, niche-based species sorting may occur among distinct soil patches (microsites), increasing diversity, and the interfaces between microsites (microedges) also may provide unique microsites. However, the influence of soil homogenization and microedges on ecosystem processes and plant responses to stress have not been examined. My thesis assessed if adding microsites containing sand, woodchips, pits or mounds increased plant species diversity, productivity, decomposition and nitrogen retention (15N tracer) and buffered plant responses to soil freezing in a tallgrass prairie restoration on former cropland. Homogenization decreased diversity in flat …
Urea As An Effective Nitrogen Source For Cyanobacteria, Kevin J. Erratt
Urea As An Effective Nitrogen Source For Cyanobacteria, Kevin J. Erratt
Electronic Thesis and Dissertation Repository
Urea use has grown substantially in the past half-century, with urea now accounting for > 50% of nitrogen fertilizer applications worldwide. The shift from inorganic nitrogen fertilizers to urea-based sources has coincided with the reappearance of cyanobacteria blooms in freshwaters. Here, we examined urea as a nitrogen source for three bloom-forming cyanobacteria species. We found that (1) urea was consumed more rapidly relative to inorganic nitrogen substrates, suggesting that cyanobacteria exhibit a preference for urea; (2) urea was consumed in excess of cellular requirements; and (3) urea may offer cyanobacteria a competitive edge over eukaryotic algae by enhancing light absorption capabilities. …
The Mixed Source Chinook Salmon Fishery In Lake Huron: A Comparison Of Spawning And Foraging Habitat Use By Naturalized And Hatchery Fish, Stephen A.C. Marklevitz
The Mixed Source Chinook Salmon Fishery In Lake Huron: A Comparison Of Spawning And Foraging Habitat Use By Naturalized And Hatchery Fish, Stephen A.C. Marklevitz
Electronic Thesis and Dissertation Repository
Chinook salmon (Oncorhynchus tshawytscha) were introduced into the Great Lakes to restore top-down control of the food web and create new recreational fisheries. Soon after introduction, naturalized spawning populations became established, and with continued stocking of hatchery fish, created a mixed source fishery. My research provides new ecological information about the contributions of naturalized fish to the mixed source Chinook salmon fishery in Lake Huron. I examined spawning and foraging habitat use by naturalized and hatchery Chinook salmon using multiple methods to identify sources of individual fish (external tags, hatchery fin clips, and otolith microchemistry). In the Sydenham …
Decomposition Dynamics Under Climate Change Conditions In Boreal Peat, Rosa Del Giudice
Decomposition Dynamics Under Climate Change Conditions In Boreal Peat, Rosa Del Giudice
Electronic Thesis and Dissertation Repository
Boreal peatlands currently act as carbon sinks, but are projected to become carbon sources under climate change. Shifts in plant community composition alongside increased decomposition rates are potential mechanisms precipitating this change. My objective was to determine the decomposition potential of different peatland plant litters (Sphagnum magellanicum (peat moss), Carex magellanica (graminoid) and Chamaedaphne calyculata (woody shrub)) during short-term (48 hour) leaching and microbial decomposition (20 week) phases. The 48-hour leaching experiment measured mass loss and leachate chemistry of litters grown under ambient and elevated CO2, while the 20-week experiment measured heterotrophic respiration and mass loss of …
Ecosystem Level Effects Of Climate Change On Northern Peatlands, Catherine M. Dieleman
Ecosystem Level Effects Of Climate Change On Northern Peatlands, Catherine M. Dieleman
Electronic Thesis and Dissertation Repository
Northern peatlands are the world’s most efficient terrestrial ecosystems at storing carbon. The effects of global climate change are expected to be intensified in high latitude regions of the northern hemisphere, where peatlands are a dominant landscape feature. Accordingly, there is concern that climate change will change peatlands from carbon sinks into carbon sources. In order to better understand the impacts of climate change on peatland ecosystems, the research presented in this dissertation focuses on several mesocosm experiments conducted to develop a better understanding of the interactive effects of three key climate change stressors (increased atmospheric CO2, increased …
Exploration Of Spatial And Temporal Changes In Trophic Status Of Lakes In The Northern Temporal Forest Biome Using Remote Sensing, Aleksey Paltsev
Exploration Of Spatial And Temporal Changes In Trophic Status Of Lakes In The Northern Temporal Forest Biome Using Remote Sensing, Aleksey Paltsev
Electronic Thesis and Dissertation Repository
There is a critical need for detailed surveys of lakes covering large spatial (>100 km2) and temporal scales (decades) to determine if there is an increase in the magnitude and frequency of phytoplankton blooms. Remote sensing was used to: (1) develop a regression model that relates chlorophyll a (chl-a) as a proxy of lake phytoplankton biomass to Landsat TM and ETM+ optical reflectance (r2=0.85, p
A Comparison Of Community Composition Analyses For The Assessment Of Responses To Wood-Ash Soil Amendment By Free-Living Nematodes, Paul B.L. George
A Comparison Of Community Composition Analyses For The Assessment Of Responses To Wood-Ash Soil Amendment By Free-Living Nematodes, Paul B.L. George
Electronic Thesis and Dissertation Repository
Land-use changes can have far-reaching consequences for resident communities and ecosystem functioning. Developing appropriate assessment methods to observe and quantify this change is an important application of community ecology. Here I compare four methods of community assessment for free-living soil nematodes under forest harvesting disturbance and wood ash application. Neither morphological assessment (richness, abundance, diversity) nor molecular assessment (morpho-richness using T-RFLP) was responsive to experimental treatments. Trait-based approaches (Maturity Index (MI) and Body Size Spectra (BSS)) were more sensitive to forest harvest and wood-ash amendment treatments. The efficacy of these methods was also qualitatively compared. Of all methods, the BSS …
Nitrogen Fixation By The Cyanobacterium Nostoc Punctiforme In Response To Variation In Nitrogen Availability, Temperature, And Atmospheric Co2 Concentrations, Danielle A. Griffith
Nitrogen Fixation By The Cyanobacterium Nostoc Punctiforme In Response To Variation In Nitrogen Availability, Temperature, And Atmospheric Co2 Concentrations, Danielle A. Griffith
Electronic Thesis and Dissertation Repository
The predominant input of available nitrogen (N) in boreal forest ecosystems originates from moss-associated cyanobacteria, which fix unavailable atmospheric N2, contribute to the soil N pool, and thereby support forest productivity. Although increases in N availability, temperature, and atmospheric CO2 concentrations are expected in Canada’s boreal region over the next century, little is known about the combined effects of these factors on N2 fixation by axenic cyanobacteria or the associated mechanisms. I assessed changes in N2 fixation by Nostoc punctiforme under different global environmental change scenarios and examined correlations between the response and changes in …
Identifying The Role Of Non-Native Species In The Enhanced Trophic Transfer Of Mercury In The Food Web Of Lake Erie, A North American Great Lake, Kaylin M.S. Liznick
Identifying The Role Of Non-Native Species In The Enhanced Trophic Transfer Of Mercury In The Food Web Of Lake Erie, A North American Great Lake, Kaylin M.S. Liznick
Electronic Thesis and Dissertation Repository
Increasing mercury (Hg) concentrations in top predatory fish is concerning for human and wildlife health. This study examined the amount of Hg available to the food web of Lake Erie, and explored the role that two recently established non-native species, dreissenid mussels and round goby, have played in the trophic transfer of Hg to sport fish. A comprehensive sampling of total Hg (THg) and methylmercury (MeHg) within Lake Erie water, sediment and seston with high temporal and spatial resolution describes environmental concentrations. In addition, biotic THg and MeHg are quantified in benthic invertebrates and three fish species. A steep spatial …
Iron-Regulated Cyanobacterial Predominance And Siderophore Production In Oligotrophic Freshwater Lakes, Ryan J. Sorichetti
Iron-Regulated Cyanobacterial Predominance And Siderophore Production In Oligotrophic Freshwater Lakes, Ryan J. Sorichetti
Electronic Thesis and Dissertation Repository
The frequency and intensity of cyanobacterial blooms (cyanoblooms) is increasing globally. Contrary to existing phosphorus (P) and nitrogen (N) paradigms describing cyanobloom proliferation in eutrophic (nutrient-rich) freshwater lakes, many of the recent cyanobloom reports pertain to oligotrophic (nutrient-poor) freshwater lakes with no prior history of cyanobloom occurrence. There exists a critical research need to re-visit existing conceptual models, identify regulating factors currently unaccounted for and improve our ability to effectively detect and measure cyanobacterial toxins (cyanotoxins) in lakes. Iron (Fe) is required in nearly all pathways of cyanobacterial macronutrient use, though its direct role in regulating cyanobacterial biomass is not …
Soil Freezing Effects On A Grass-Dominated Old Field Ecosystem Under Current And Future Rates Of Atmospheric Nitrogen Deposition, Mat Vankoughnett
Soil Freezing Effects On A Grass-Dominated Old Field Ecosystem Under Current And Future Rates Of Atmospheric Nitrogen Deposition, Mat Vankoughnett
Electronic Thesis and Dissertation Repository
Climate change is expected to alter the intensity and dynamics of soil freezing as a result of increased air temperatures and reduced snow cover. Soil freezing can influence ecosystem nitrogen (N) cycling by damaging plants and soil microorganisms, but little is known about how soil freezing effects on ecosystem N cycling may combine or interact with increased atmospheric N deposition, which is also expected to exert a strong influence on terrestrial ecosystems in the coming decades. The objective of my thesis was to examine the combined and possibly the interactive effects of climate induced changes in soil freezing and N …
Tree Seedling Establishment In Response To Warming And Nitrogen Addition In A Temperate Old Field, Bryana D. Mcwhirter
Tree Seedling Establishment In Response To Warming And Nitrogen Addition In A Temperate Old Field, Bryana D. Mcwhirter
Electronic Thesis and Dissertation Repository
Climate change and increased atmospheric nitrogen deposition over the next century may alter the ability of woody species to germinate and compete with grasses and forbs in temperate old fields. To investigate the responses of seed germination and seedling growth to warming and nitrogen addition, I transplanted seeds and seedlings into plots of a field experiment and conducted a greenhouse experiment. The combination of warming and nitrogen allowed seeds to germinate earlier, although there was no effect on final germination. In the greenhouse nitrogen increased seedling growth, and warming had little effect. However, in the field, warming significantly decreased the …
Interactions Among Biotic And Abiotic Controls Of Carbon Dynamics In A Global Change Field Experiment, Eric R D Moise
Interactions Among Biotic And Abiotic Controls Of Carbon Dynamics In A Global Change Field Experiment, Eric R D Moise
Electronic Thesis and Dissertation Repository
Climate warming and increased atmospheric nitrogen deposition may substantially influence biosphere C cycling over the next century by altering ecosystem processes such as productivity and decomposition. Field studies are commonly used to explore plant responses to global change, although the underlying mechanisms can be difficult to isolate owing to the lack of control of factors such as plant-animal interactions. Ultimately, indirect effects via herbivore and detritivore responses may feedback to influence plant responses to the experimental treatments. The goal of this thesis was to explore interactions among biotic and abiotic drivers of carbon dynamics within the context of experimental warming …
Structure Of An Ensemble Of Insectivorous Bats, Matthew A. Emrich
Structure Of An Ensemble Of Insectivorous Bats, Matthew A. Emrich
Electronic Thesis and Dissertation Repository
Ensembles of species show distinct characteristics that may permit resource partitioning but few studies focus on more than one or two traits. Using seven sympatric Jamaican bats, I examined features which could allow for spatial, temporal, behavioural and dietary partitioning including wing morphology, echolocation characteristics, flight behaviour, habitat use, and diet. Using acoustic arrays I compared activity patterns at different sites to determine temporal and spatial partitioning and generated flight paths to determine flight speeds. From captured bats I measured wing morphology to examine morphological differences and did genetic analysis of guano to determine dietary partitioning. Morphology, call structure and …