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Articles 1 - 30 of 40
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Extinction Anxiety As Zeitgeist: An Examination Of The Cultural Anxiety Surrounding Extinction Threats, Spencer J. Kett
Extinction Anxiety As Zeitgeist: An Examination Of The Cultural Anxiety Surrounding Extinction Threats, Spencer J. Kett
Electronic Thesis and Dissertation Repository
This thesis examines extinction anxiety as a zeitgeist that manifests through nuclear war anxiety and climate change anxiety. I define extinction anxiety as the cultural mood of anxiousness surrounding extinction threats in the past, present, and future. I use Monika Krause’s sociological conception of zeitgeist to understand these anxieties as a cultural mood. I demonstrate using Jean-Paul Sartre’s conceptualization of materially derived subjectivity, how these moods of anxiousness are internalized through material conditions. I build my concept of extinction anxiety by comparing and contrasting the mood of anxiousness surrounding nuclear war during the Cold War and the current mood of …
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 …
Creative Common Worlding With Research Creation In Early Childhood Education, Sarah M. Hennessy
Creative Common Worlding With Research Creation In Early Childhood Education, Sarah M. Hennessy
Electronic Thesis and Dissertation Repository
Creative Common worlding with research-creation in early childhood education engages with provocations that disrupt dominant understandings of children and their relations with more-than-human and human others. Reconceptualizing alternatives through art, this dissertation contemplates the potent possibilities beyond human stewardship, underscores the influence of an uncommoning lens, and emphasizes the difficulties with humancentric notions of research. If, by disrupting how we understand ourselves and our role in place, we modify our actions and change our habits, then perhaps we can live differently and contribute differently to the planet. Through a common worlds framework together with research-creation, this dissertation considers climate education …
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 …
Temperature-Dependent Developmental Plasticity In The Cardiorespiratory System Of Atlantic Salmon, Carlie A. Muir
Temperature-Dependent Developmental Plasticity In The Cardiorespiratory System Of Atlantic Salmon, Carlie A. Muir
Electronic Thesis and Dissertation Repository
Anthropogenic climate change is expected to have pervasive impacts on the performance and viability of fishes, as increasing temperatures create aerobically constrained environments for many species. Given the rapid rates of projected temperature increases, it is critical to evaluate the capacity for fish to respond to a changing thermal environment through phenotypic plasticity. In this thesis, I examined the capacity for developmental plasticity in the thermal performance of juvenile Atlantic salmon (Salmo salar) reared under two thermal regimes from fertilization, and investigated potential mechanistic underpinnings within the cardiorespiratory system. Cardiac performance was examined using a noninvasive Doppler echocardiograph …
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, …
Allostratigraphy Of The Lower Colorado Group (Cretaceous) In South-West Alberta, Slavena Galic
Allostratigraphy Of The Lower Colorado Group (Cretaceous) In South-West Alberta, Slavena Galic
Electronic Thesis and Dissertation Repository
Clastic, upper Albian-lower Cenomanian strata were deposited in a low-accommodation backbulge depozone of the Western Canada Foreland Basin in SW Alberta. These strata are lithologically very heterogeneous and encompass a spectrum of depositional environments along an alluvial to offshore transect. These rocks are assigned, in subsurface, to the Lower Colorado Group, and in outcrop to the upper Blairmore Group. Lithological heterogeneity, as a result of rapid lateral facies changes, resulted in diverse nomenclature that obscured genetic relationships between time-equivalent strata. The present study integrates wireline log, core, and outcrop data to establish a high-resolution allostratigraphic framework which allowed recognition of …
Climate Change Vulnerability And Perceived Resilience Among Smallholder Farmers In The Upper West Region Of Ghana, Evans Sumabe Batung
Climate Change Vulnerability And Perceived Resilience Among Smallholder Farmers In The Upper West Region Of Ghana, Evans Sumabe Batung
Electronic Thesis and Dissertation Repository
Globally, observed climate change has become a major barrier to agricultural productivity. At the same time, present and projected climate impacts are disproportionately affecting smallholder farmers in sub-Saharan Africa (SSA) where smallholder agriculture constitutes the predominant source of livelihood. Due to the vast agricultural potential of SSA, climate change resilience has been central in several multi-level deliberations over the past few decades. However, existing policies aimed at improving the effects of climate change on food security have overwhelmingly focused on the climatic dimensions of vulnerability, resulting in a lack of knowledge of the role non-climatic factors also play in shaping …
Impacts Of Climate Change On Food Security And Smallholder Livelihoods In Northern Ghana, Kamaldeen Mohammed
Impacts Of Climate Change On Food Security And Smallholder Livelihoods In Northern Ghana, Kamaldeen Mohammed
Electronic Thesis and Dissertation Repository
Climate change and food insecurity threaten the livelihoods of smallholder communities in the Global South. In the Ghanaian context, climate change and food insecurity are particularly crucial challenges in the northern regions, where most people are engaged in diverse activities in the agricultural sector. Despite tremendous efforts to curtail food insecurity and climate change vulnerability of smallholder households in northern Ghana, food insecurity and climate change remain pervasive in the region, indicating that smallholder adaptive capacities and resilience to the impacts of climate change are not commensurate with the severity of the problems. Emerging literature has indicated that livelihood diversification …
Ground Warming Leads To Changes In Carbon Cycling In Northern Fen Peatlands: Implications For Carbon Storage, Ericka James
Ground Warming Leads To Changes In Carbon Cycling In Northern Fen Peatlands: Implications For Carbon Storage, Ericka James
Electronic Thesis and Dissertation Repository
Northern peatlands store one third of the world’s soil carbon (C), as they remove more C from the atmosphere via photosynthesis than they release to the atmosphere through ecosystem respiration and methane (CH4) production. Climate change threatens this function by stimulating C release from peatland stores as peat temperatures warm and soil moisture is reduced. Ground heating of +4 °C above ambient peat temperatures was initiated in a Sphagnum moss-dominated, nutrient poor fen and a Carex sedge-dominated, intermediate nutrient fen. Over one growing season, Carex fen heated plots had increases in photosynthesis (+23%), ecosystem respiration (+22%), and CH …
Floral Traits And Carbon Dynamics Of Cucumber In Response To Climate Change, Sarah Josina Mcdonald
Floral Traits And Carbon Dynamics Of Cucumber In Response To Climate Change, Sarah Josina Mcdonald
Electronic Thesis and Dissertation Repository
Pollination by animals is an important ecosystem service that contributes to the reproduction of many angiosperms. Climate change may alter this mutualism by affecting floral traits that are important to pollinators. Using Cucumis sativus, I tested the effects of experimentally elevated temperature and CO2 concentration on flowering onset, flower number, flower size, and floral rewards. Additionally, to better understand plant carbon balance and investment in reproduction, I measured biomass partitioning and leaf carbon fluxes of plants under their growth conditions. Carbon dynamics were similar across treatments, and plants grown under high [CO2] and temperature showed similar …
Investigating The Role Of Carbon Stress In The Mortality Of Tamarack Seedlings Under A Warming Environment, Bridget K. Murphy
Investigating The Role Of Carbon Stress In The Mortality Of Tamarack Seedlings Under A Warming Environment, Bridget K. Murphy
Electronic Thesis and Dissertation Repository
Climate warming is increasing the frequency of climate-induced tree mortality events. While drought combined with heat is considered the primary cause of this tree mortality, little is known about whether high temperatures alone can induce mortality, or whether rising CO2 will increase survival. I grew tamarack in two experiments combining warming (0-8 ˚C above ambient) and CO2 (400-750 ppm) to investigate whether high growth temperatures led to carbon limitations and mortality. Using glasshouses, +8 ˚C warming with ambient CO2 (8TAC) led to 40% mortality despite thermal acclimation of respiration. Dying 8TAC seedlings had lower needle carbon concentrations …
Effects Of Elevated Temperature And Elevated Co2 On Leaf Carbon Fluxes In Boreal Conifers: Lab And Field Studies, Mirindi Eric Dusenge
Effects Of Elevated Temperature And Elevated Co2 On Leaf Carbon Fluxes In Boreal Conifers: Lab And Field Studies, Mirindi Eric Dusenge
Electronic Thesis and Dissertation Repository
Rising CO2 may warm northern latitudes up to 10 °C by the end of the century. However, responses of plant physiological processes (such as photosynthesis and respiration) and growth to climate change remain uncertain. Seedlings and mature trees of tamarack (a deciduous species) and black spruce (an evergreen species), North America dominant conifers, were exposed to combined warming (up to +9 ˚C) and elevated CO2 (up to +300 ppm). In seedlings, stomatal conductance (gs) tended to increase with warming in tamarack seedlings, while gsdeclined with warming in spruce. In both species, CO2 had …
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 …
Future Changes Of Hydroclimatic Extremes In Western North America Using A Large Ensemble: The Role Of Internal Variability, Mohammad Hasan Mahmoudi
Future Changes Of Hydroclimatic Extremes In Western North America Using A Large Ensemble: The Role Of Internal Variability, Mohammad Hasan Mahmoudi
Electronic Thesis and Dissertation Repository
Increases in the intensity and frequency of extreme events in Western North America (WNA) can cause significant socioeconomic problems and threaten existing infrastructure. In this study we analyze the impacts of climate change on hydroclimatic extremes and assess the role of internal variability over WNA, which collectively drain an area of about 1 million km2. We used gridded observations and downscaled precipitation, maximum and minimum temperature from seven General Circulation Models (GCMs) that participated in the Coupled Model Intercomparison Project Phase 5 (CMIP5) and a large ensemble of CanESM2 model simulations (CanESM2-LE; 50 members) for this analysis. Spatial …
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 …
Modelling Of Future Flood Risk Across Canada Under Climate Change, Ayushi Gaur
Modelling Of Future Flood Risk Across Canada Under Climate Change, Ayushi Gaur
Electronic Thesis and Dissertation Repository
Climate change has induced changes in key climate variables and hydrological cycle in Canada. In this study, future runoff projections made by 21 GCMs following four Representative Concentration Pathways (RCPs) are used as inputs into a macro-scaled hydrodynamic model: CaMa-Flood to simulate 25 km resolution daily streamflow across Canada for historical (1961-2005) and future (2061-2100) time-periods. Future changes in flood-hazard as a consequence of changes in flooding frequencies of historical 100-year and 250-year return period flood events, and changes in the month of occurrence of extreme flows are analyzed. Changes in flood risk at Canada’s 100 most populous cities and …
Elevated Temperature And Co2 Concentrations Affect Carbon Flux In Two Boreal Conifers, Sasha Madhavji
Elevated Temperature And Co2 Concentrations Affect Carbon Flux In Two Boreal Conifers, Sasha Madhavji
Electronic Thesis and Dissertation Repository
Elevated temperatures and CO2 will alter carbon flux in two dominant boreal tree species Picea mariana (black spruce) and Larix laricina (tamarack). Trees were grown in three temperature treatments (ambient, ambient +4 °C, and ambient +8 °C) at either 400 ppm or 750 ppm CO2, to simulate climate conditions between now and the year 2100. Spruce acclimated to increasing temperature detractively; warming scenarios reduced spruce net carbon gain. Tamarack maintained comparable levels of net photosynthesis (Anet) across warming treatments and both species acclimated respiration (Rdark) with increasing growth temperature. Elevated CO2-grown …
Uncertainty Modeling In The Assessment Of Climate Change Impacts On Water Resources Management, Sohom Mandal
Uncertainty Modeling In The Assessment Of Climate Change Impacts On Water Resources Management, Sohom Mandal
Electronic Thesis and Dissertation Repository
Climate change has significant impacts on water resource systems. The objective of this study is to assess climate change impacts on water resource management. The methodology includes (a) the assessment of uncertainty introduced by choice of precipitation downscaling methods; (b) uncertainty assessment and quantification of the impact of climate change on projected streamflow; and (c) uncertainty in and impact of climate change on the management of reservoirs used for hydropower production. The assessment is conducted for two future time periods (2036 to 2065 and 2066 to 2095). The study area, Campbell River basin, British Columbia, Canada, consists of three reservoirs …
The Impacts Of Climate Change On Communities Of Fungi In Boreal Peatlands, Asma Asemaninejad Hassankiadeh
The Impacts Of Climate Change On Communities Of Fungi In Boreal Peatlands, Asma Asemaninejad Hassankiadeh
Electronic Thesis and Dissertation Repository
Peatlands have an important role in global climate change through sequestration of atmospheric CO2. Climate change is already affecting these ecosystems, including both above- and below- ground communities and their functions. Fungi play a central role in these communities. As a result, there is concern that altered fungal community function may turn peatlands from carbon sinks to carbon sources, greatly exacerbating the impacts of climate change. In order to gain a better insight into effects of climate change on the structure and function of these carbon sequestrating ecosystems, this thesis focuses on diversity and structure of fungal communities …
Regulating For Resilience: Principled Flexibility And Environmental Co-Management In The Mackenzie Valley, Heather L. Potter
Regulating For Resilience: Principled Flexibility And Environmental Co-Management In The Mackenzie Valley, Heather L. Potter
Electronic Thesis and Dissertation Repository
The author examines the environmental regulatory regime in the Mackenzie Valley region of the Northwest Territories which includes the regulatory structure established by the Mackenzie Valley Resource Management Act and the private contractual instruments of environmental agreements, impact benefit agreements and socio-economic agreements. The author concludes that these instruments work together to form a complex regulatory system that is sometimes maladapted to the adaptive management framework necessary for effective regulation in an increasingly unstable arctic environment. The author argues that effective environmental management in the Mackenzie Valley requires a regulatory approach grounded in principled flexibility and shared environmental goals across …
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 …
A Physical Scaling Method To Incorporate Regional Physical Characteristics In Future Climatic And Hydrologic Predictions, Abhishek Gaur
A Physical Scaling Method To Incorporate Regional Physical Characteristics In Future Climatic And Hydrologic Predictions, Abhishek Gaur
Electronic Thesis and Dissertation Repository
In this thesis an original Physical Scaling (SP) method for downscaling Global Circulation Model (GCM) based climatic projections has been developed, tested and applied over a study region. The model formulation can take into account regional physical characteristics like land-cover and elevation into the model formulation. A thorough verification of the method and its extension: SP with Surrounding pixel information (SPS) method has been performed and their performance towards downscaling GCM based precipitation, surface temperature and air temperature has been compared with many state-of-the-art downscaling models like Bias Correction Spatial Downscaling (BCSD) method, Statistical DownScaling Method (SDSM) and Generalized Linear …
A Systems Approach To Modelling The Effects Of Climate Change On Agroforestry: A Case Study In Western Tanzania, Elaine M. Samuel
A Systems Approach To Modelling The Effects Of Climate Change On Agroforestry: A Case Study In Western Tanzania, Elaine M. Samuel
Electronic Thesis and Dissertation Repository
Climate change is anticipated to have significant effects on agricultural production in sub-Saharan Africa as the magnitude of weather events increase in severity. Smallholder farmers in western Tanzania are potentially vulnerable to climate change impact as crops rely on precipitation as the only source of water. It is prudent to evaluate different modes of agricultural adaptations, such as agroforestry, that these farmers can easily adopt to improve their resiliency to the effects of climate change. System dynamics modelling is a cost-effective tool to simulate the long-term behaviour of agroforestry systems under future climate conditions. Water, Nutrient, and Light Capture in …
Environment And Human Health In The Anthropocene: Interaction Between Natural And Social Systems In Coastal Tanzania, Frederick A. Armah
Environment And Human Health In The Anthropocene: Interaction Between Natural And Social Systems In Coastal Tanzania, Frederick A. Armah
Electronic Thesis and Dissertation Repository
Coastal Tanzania, a region of historical and geopolitical importance in the western Indian Ocean, is a place where the problem of rapid environmental change is inextricably entwined with the challenges of development. In this region, although the fingerprint of the anthropocene has been discernible over the last century, there is paucity of research on how the population has interacted with the changing environment to generate disparities in perceptions of climate change and human health outcomes. The objectives of this thesis are four-fold: to assess barriers to climate change adaptation based on context (place), to explain group disparities in barriers to …
Thermal Performance Covaries With Environmental Temperature Across Populations Of Atlantic Salmon (Salmo Salar), Kayla J. Harding Gradil
Thermal Performance Covaries With Environmental Temperature Across Populations Of Atlantic Salmon (Salmo Salar), Kayla J. Harding Gradil
Electronic Thesis and Dissertation Repository
Global climate change is projected to have widespread effects that could threaten the viability of natural populations. Physiological processes of aquatic ectotherms critically depend on their thermal environment, such that the optima for performance often correspond to environmental temperatures. Given predicted changes in aquatic thermal environments, it is increasingly important to understand organism’s underlying physiological mechanisms utilized to cope with these changes. Here, I show that three populations of Atlantic salmon (Salmo salar) are narrowly adapted to their native summer temperatures, such that thermal tolerance is optimized near average temperatures and collapses near peak temperatures. Further, I found …
Potential Effects Of Changing Climate On The Physical, Chemical, And Biological Characteristics Of Alpine Lakes, Uinta Mountains, Utah, Usa, Shirley Ngai
Electronic Thesis and Dissertation Repository
Relationships between climate variables, lake characteristics and diatom community composition were determined for five lakes in the Uinta Mountains, Utah (USA) from spring 2010 to autumn 2013 to provide information to help predict the effects of climate change on lake ecosystems. Surface water temperatures increased with decreasing elevation although microclimates affected this relationship. Deeper water temperatures increased or stayed the same with increasing elevation, probably due to greater transparency or convective heating. Total phosphorus (TP) and chl a concentrations decreased in the spring/summer with warmer fall/winter temperatures, and nitrates in the spring increased with increased fall/winter precipitation. A significant correlation …
The Effects Of Global Climate Change On Canadian Boreal Forest Collembola Communities, Matthew S. Turnbull
The Effects Of Global Climate Change On Canadian Boreal Forest Collembola Communities, Matthew S. Turnbull
Electronic Thesis and Dissertation Repository
Soil fauna are an integral component of terrestrial ecosystem function. The effects of global environmental change on soil biodiversity are poorly studied, particularly interactions among temperature, atmospheric CO2, precipitation intensity, and nutrient loading. Body size distributions can be used to quantify soil community responses to perturbation and consequences for ecosystem function. I quantified top-down and bottom-up effects of environmental change on the abundance, richness, and size distribution of the soil microarthropod group Collembola. I demonstrated negative effects in a lab experiment of increased precipitation on collembolan density and richness across all size groups. I demonstrated positive effects in …
The Adaptive Capacity Of Thermal Tolerance In Chinook Salmon, Nicolas Muñoz
The Adaptive Capacity Of Thermal Tolerance In Chinook Salmon, Nicolas Muñoz
Electronic Thesis and Dissertation Repository
With global temperatures projected to surpass the limits of thermal tolerance for many species, evaluating the capacity for evolutionary and phenotypically plastic changes in thermal tolerance is key to our understanding of the biological consequences of climate change. Within quantitative genetic breeding designs and multiple rearing environments, I measured the thermal performance of cardiac function among families of two populations of chinook salmon (Oncorhynchus tshawytscha). I found significant indirect genetic, plastic, and additive genetic effects contributing to cardiac performance and thermal tolerance, representing a variety of adaptive mechanisms available to salmon populations faced with climate change. These results …
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 …