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Climate change

2016

Theses/Dissertations

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Articles 1 - 30 of 35

Full-Text Articles in Life Sciences

Impacts Of Long-Term Precipitation Manipulation On Hydraulic Architecture, Xylem Function, And Canopy Status In A Piñon-Juniper Woodland, Patrick J. Hudson Dec 2016

Impacts Of Long-Term Precipitation Manipulation On Hydraulic Architecture, Xylem Function, And Canopy Status In A Piñon-Juniper Woodland, Patrick J. Hudson

Biology ETDs

The Southwestern US is predicted to become hotter and drier, as global climate change forces increasing temperatures and variability in timing and size of precipitation inputs. Drought stress has become more frequent in recent decades, and resulted in massive forest mortality in piñon-juniper woodlands. During recent severe droughts (2000-2003, 2009-2012), piñon pine (Pinus edulis Englem.) suffered disproportionately high mortality compared to co-occurring one-seed juniper (Juniperus monosperma [Engelm.] Sarg.). A large-scale precipitation manipulation experiment was established in a piñon-juniper woodland in central New Mexico to test hypotheses regarding tree survival and mortality with respect to altered water regimes. Our treatments consisted ...


The Impacts Of Climate Change On Communities Of Fungi In Boreal Peatlands, Asma Asemaninejad Hassankiadeh Dec 2016

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 in ...


Exploring Enrichment Cultures Of Denitrifying Microorganisms From El Yunque National Forest, Samiha Ahsan, Jenny Onley, Frank Loeffler Dec 2016

Exploring Enrichment Cultures Of Denitrifying Microorganisms From El Yunque National Forest, Samiha Ahsan, Jenny Onley, Frank Loeffler

Chancellor’s Honors Program Projects

No abstract provided.


Linking Rising Pco2 And Temperature To The Larval Development, Physiology And Gene Expression Of The American Lobster (Homarus Americanus), Jesica Waller Nov 2016

Linking Rising Pco2 And Temperature To The Larval Development, Physiology And Gene Expression Of The American Lobster (Homarus Americanus), Jesica Waller

Electronic Theses and Dissertations

Anthropogenic warming and ocean acidification are occurring as CO2 continues to accumulate in the atmosphere (OA). Few studies have evaluated the joint effects of elevated temperature and partial pressure of CO2 (pCO2)on marine organisms. In this study we investigated the interactive effects of Intergovernmental Panel on Climate Change (IPCC) predicted temperature and pCO2 for the end of the 21st century on key aspects of larval development of the American lobster, Homarus americanus, an otherwise well-studied, iconic, and commercially prominent species in the northeastern United States and Atlantic Canada. Our experiments showed that larvae ...


Climate Change Drives Outbreaks Of Emerging Infectious Disease And Phenological Shifts, Jeremy Cohen Nov 2016

Climate Change Drives Outbreaks Of Emerging Infectious Disease And Phenological Shifts, Jeremy Cohen

Graduate Theses and Dissertations

Climate change is expected to impact species by altering infectious disease outcomes, modifying community composition, and causing species to shift their phenology, body sizes and range distributions. However, the outcomes of these impacts are often controversial; for example, scientists have debated whether climate change will exacerbate emerging infectious disease and which species are at greatest risk to advance their phenology. There reason for these controversies may be that climate change is impacting diverse processes across a wide range of ecological scales, as the interplay between fine-scale processes and broad-scale dynamics can often cause unpredictable changes to the biosphere. Therefore, it ...


Coarse Root Biomass And Architecture: Applications Of Ground Penetrating Radar, John Claude Bain Oct 2016

Coarse Root Biomass And Architecture: Applications Of Ground Penetrating Radar, John Claude Bain

Biological Sciences Theses & Dissertations

The effectiveness of ground penetrating radar (GPR) to identify and quantify coarse roots was tested in a mixed-oak forest in Southeastern Virginia using experimental pits and locally excavated root segments. GPR was found to be highly dependent on low soil moisture levels as it is unable to differentiate root structures if they possess similar moisture content as their surrounding soil. Likewise, GPR was unable to identify simulated dead roots. This does not alter the effectiveness of GPR to measure living coarse root biomass, but does present the potential for underestimation of carbon storage in coarse root structures, as a dead ...


Decomposition Dynamics Under Climate Change Conditions In Boreal Peat, Rosa Del Giudice Aug 2016

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 litters incubated ...


Evolutionary Potential Of A Dispersal-Restricted Species In Response To Climate Change, Lorena Torres Martinez Aug 2016

Evolutionary Potential Of A Dispersal-Restricted Species In Response To Climate Change, Lorena Torres Martinez

Open Access Dissertations

Habitat replacement and fragmentation associated with projected climate change pose a critical threat to global biodiversity. Edaphically limited plant species with restricted dispersal abilities will be especially handicapped to track their optimal climate spatially. Instead, the persistence of these species will depend on their capacity to adapt in situ to novel climate regimes. Here I evaluated the evolutionary potential of Lasthenia fremontii, an annual plant species restricted to ephemeral wetlands called vernal pools in California to adapt to the projected patterns of climate change. Across L. fremontii distribution there is a latitudinal gradient in precipitation which, combined with reduced gene ...


The Effect Of Climate Change On The Economics Of Conservation Tillage: A Study Based On Field Experiments In Indiana, Whitney Hodde Aug 2016

The Effect Of Climate Change On The Economics Of Conservation Tillage: A Study Based On Field Experiments In Indiana, Whitney Hodde

Open Access Theses

This study evaluates the economics of conservation tillage (chisel till and no till) and examines how climate change will likely affect it. We use data from long-term experimental plots in Indiana to estimate how corn and soybean yields respond to weather patterns under alternative tillage practices. Yield functions are coupled with random draws of weather variables to construct distributions describing the probability that conservation tillage will result in higher profits than more intensive tillage, under current and future climatic regimes. Results suggest that, in our study area, projected climate change will make conservation tillage more attractive.


Irrigation Adoption, Groundwater Demand And Policy In The U.S. Corn Belt, 2040-2070, Molly A. Van Dop Aug 2016

Irrigation Adoption, Groundwater Demand And Policy In The U.S. Corn Belt, 2040-2070, Molly A. Van Dop

Open Access Theses

Climate change across the U.S. Corn Belt will significantly increase precipitation variability and temperatures by midcentury. Corn and soybean producers will seek to find strategies that may help to mitigate the potentially negative effects on yield. The adoption of irrigation technology has increased over the last several decades to improve yields in areas with insufficient rainfall, and is currently being adopted by producers who are choosing to minimize risk due to weather variability. To see if this trend in irrigation adoption has the potential to expand in the wake of climate change, this study uses weather data from four ...


Gyrfalcon Diet During The Brood Rearing Period On The Seward Peninsula, Alaska, In The Context Of A Changing World, Bryce W. Robinson Aug 2016

Gyrfalcon Diet During The Brood Rearing Period On The Seward Peninsula, Alaska, In The Context Of A Changing World, Bryce W. Robinson

Boise State University Theses and Dissertations

As climate change impacts increase so does our need to understand their effects on ecosystem dynamics. I studied Gyrfalcon (Falco rusticolus) diet during the brood rearing period to improve our knowledge on dietary habits during nesting, and provide necessary information for understanding climate change impacts to Arctic ecosystems. I studied diet over two breeding seasons on the Seward Peninsula, Alaska, using two methods: motion-activated cameras and the collection of prey remains. I observed three important dietary shifts: the proportion of ptarmigan in the diet declined significantly throughout the season, the proportion of large prey items declined significantly throughout the season ...


The Impact Of Climate Change In Bangladesh On The Rice Market And Farm Households, Mst Ashrafun Nahar Aug 2016

The Impact Of Climate Change In Bangladesh On The Rice Market And Farm Households, Mst Ashrafun Nahar

Theses and Dissertations

Bangladesh is trying to achieve self-sufficiency in domestic rice production but climate change effects on agricultural production makes it challenging to attain the goal. The country is highly vulnerable to the effects of climate change since it is the major cause to rise in sea level, more warm summer, and happening food and cyclone in the country.

This study develops an Aggregate Farm Household Model to analyze the impact of potential land loss and yield reduction from climate change on production, consumption, prices, welfare, and the ability of government to achieve self-sufficiency in rice production. The model is calibrated to ...


Agro-Climatic Change, Crop Production And Mitigation Strategies-Case Studies In Arkansas, Usa And Kenya, John Westley Magugu Aug 2016

Agro-Climatic Change, Crop Production And Mitigation Strategies-Case Studies In Arkansas, Usa And Kenya, John Westley Magugu

Theses and Dissertations

Although climate change impacts vary geographically and temporally, studies at local levels are not readily available for stakeholders to better understand how their local communities would be affected and what remedial measures could be more effective in their local contexts. This dissertation has examined climate change and its impacts in two different local contexts: eastern Arkansas in the USA and Nyando in Kenya. The first part of this dissertation develops agro-meteorological indicators and examines the relationship between agro-meteorological indicators and crop yields in eastern Arkansas between 1960 and 2014. Results reveal that temperature based indicators were more strongly correlated to ...


Coral Persistence To Ocean Warming Via Developmental Acclimation, Heather L. Schaneen Jul 2016

Coral Persistence To Ocean Warming Via Developmental Acclimation, Heather L. Schaneen

HCNSO Student Theses and Dissertations

Scleractinian corals are the ‘engineers’ of tropical coral reef ecosystems. Their three-dimensional structure provides habitat for thousands of fish and invertebrate species. The persistence of corals is threatened by climate change. In this study I investigated if corals may be able to increase tolerance to ocean warming through developmental acclimation, i.e. if corals that experience warmer temperatures during embryonic and larval development are better able to cope with higher temperatures later in life. Larvae of the broadcast spawning coral Montastraea cavernosa were raised at ambient (29°C) and future projected ocean warming temperatures (+2°C, 31°C). After larval ...


Monitoring And Mitigation Of Elevated Co2 Impacts Using Microalgae, Terry-Rene Wiesner Brown Jul 2016

Monitoring And Mitigation Of Elevated Co2 Impacts Using Microalgae, Terry-Rene Wiesner Brown

Graduate Theses and Dissertations

Climate change is arguably the greatest environmental and economic challenge of our time. There are considerable documented and projected impacts to both human and natural systems as a result of climate change. These impacts include changes in temperature, sea level, precipitation patterns, and biogeography of ecologically and economically relevant species, including pathogens. One of the main drivers of climate change is elevated levels of atmospheric carbon dioxide (CO2), a greenhouse gas. Since pre-industrial times, atmospheric CO2 levels have increased from approximately 280 ppm to over 400 ppm, as a result of fossil fuel combustion, cement production and land ...


A Systems Approach To Modelling The Effects Of Climate Change On Agroforestry: A Case Study In Western Tanzania, Elaine M. Samuel May 2016

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 ...


Examining The Growth And Performance Of The Effect Of Uv-B Radiation On United Arab Emirates Date Palm Tree (Phoenix Dactylifera), Saeedallah Abdulwali Niazwali May 2016

Examining The Growth And Performance Of The Effect Of Uv-B Radiation On United Arab Emirates Date Palm Tree (Phoenix Dactylifera), Saeedallah Abdulwali Niazwali

Theses

The stratospheric ozone depletion and elevated solar UV-B radiation have a negative effect on living life forms. UV radiation is one of the unsafe components that cause hindrance to both flora and fauna on the earth. This will have important implications for ecosystem processes and food production. The present study has been designed with primary objective of the effect of UV-B radiation on five numbers of most cultivated Emirates varieties (i.e., BARHI, FRDWT, NBTSF, FRDRD and KHD). After 4 and 8 hrs/day UVB treatment the Shoot, Root and total Plant length, Total plant fresh weight, Shoot and Root ...


The Effects Of Large Herbivores On Soil Organic Matter Quality In Terrestrial Ecosystems, Adrian Alvarez May 2016

The Effects Of Large Herbivores On Soil Organic Matter Quality In Terrestrial Ecosystems, Adrian Alvarez

Syracuse University Honors Program Capstone Projects

Understanding the factors that control the natural fluxes of carbon into and out of terrestrial ecosystems is of paramount importance to forecast and adapt to climate change. Soil respiration – the release of carbon dioxide from roots and soil micro-organisms– is considered to be the largest terrestrial source of carbon dioxide. Microbial respiration, the least understood component of soil respiration, is to a great extent determined by soil organic matter quality, reflecting the relative fractions of labile and recalcitrant soil carbon. The goal of this research was to examine how herbivory affects soil organic matter quality across a wide range of ...


Rapid Savanna Response To Changing Precipitation Intensity, Ryan S. Berry May 2016

Rapid Savanna Response To Changing Precipitation Intensity, Ryan S. Berry

All Graduate Theses and Dissertations

As the atmosphere warms, precipitation events are likely to become less frequent but more intense. While extensive efforts have been made to understand how changes in mean annual precipitation will affect plant growth, particularly in semi-arid systems, relatively little is known about how increasing precipitation intensity will affect plant growth and hydrologic cycles. A recent study by Kulmatiski and Beard (2013) found that small increases in precipitation intensity increased woody plant growth and decreased grass growth in a three-year experiment in a savanna system, Kruger National Park. Here we report results from the following two years of that experiment. Due ...


A Spatiotemporal Mountain Pine Beetle Outbreak Model Predicting Severity, Cycle Period, And Invasion Speed, Jacob P. Duncan May 2016

A Spatiotemporal Mountain Pine Beetle Outbreak Model Predicting Severity, Cycle Period, And Invasion Speed, Jacob P. Duncan

All Graduate Theses and Dissertations

The mountain pine beetle (MPB, Dendroctonus ponderosae), a tree-killing bark beetle, has historically been part of the normal disturbance regime in lodgepole pine (Pinus contorta) forests. In recent years, warm winters and summers have allowed MPB populations to achieve synchronous emergence and successful attacks, resulting in widespread population outbreaks and resultant tree mortality across western North America. We develop an age-structured forest demographic model that incorporates temperature-dependent MPB infestations: the Susceptible-Infested-Juvenile (SIJ) model. Stability of fixed points is analyzed as a function of population growth rates, and indicates the existence of periodic outbreaks that intensify as growth rates increase. We ...


Detection And Attribution Of Long-Term Vegetation Changes In Northern Alaska, Robert Barrett Apr 2016

Detection And Attribution Of Long-Term Vegetation Changes In Northern Alaska, Robert Barrett

Masters Theses

Climate change is impacting terrestrial ecosystems world-wide and the Arctic is particularly vulnerable as it is warming faster and with greater magnitude than other regions. Understanding the responses of arctic plants species to abiotic factors is crucial to predicting the impact climate change will have on the Arctic because plants play critical roles in carbon exchange, energy balance, and trophic interactions. Using data from long-term research sites in Barrow and Atqasuk, Alaska, the purpose of this thesis was to investigate how arctic plants respond to 17-19 years of experimental warming, establish the relative strengths of various abiotic factors in predicting ...


Using Glycosylated Hemoglobin And Heat Shock Protein 70 As Thermal Biomarkers In North American Pikas (Ochotona Princeps), Steven Edmonds Apr 2016

Using Glycosylated Hemoglobin And Heat Shock Protein 70 As Thermal Biomarkers In North American Pikas (Ochotona Princeps), Steven Edmonds

Life and Environmental Sciences Undergraduate Theses

Pikas (Ochotona princeps), high altitude lagomorphs, are potentially one of the first mammals to be directly affected by global warming. Population decline has been observed in pika populations in Nevada and California. The cause of their decline is unknown but several studies suggest that heat stress, especially at lower altitudes, is a contributing factor. In Montana, populations are potentially stressed in the same way. One hypothesis is that direct thermal stress is causing population decline. This study looks at heat shock protein 70 (HSP70) and glycosylated hemoglobin levels in high and low altitude pika populations as biomarkers for thermal stress ...


Modeling Historical And Future Range Of Variability Scenarios In The Yuba River Watershed, Tahoe National Forest, California, Maritza Mallek Jan 2016

Modeling Historical And Future Range Of Variability Scenarios In The Yuba River Watershed, Tahoe National Forest, California, Maritza Mallek

Masters Theses

In California's northern Sierra Nevada mountains, the fire-dependent processes of forest ecosystems have been interrupted and altered by human land use and fire suppression. U.S. Forest Service policy directs land managers to plan for a future that includes multiple use and the restoration of resilient ecosystems. Planning decisions are to be informed by an analysis of the range of variability of ecological processes at multiple scales. Current climate trends in the northern Sierra are of increasing temperatures, increased precipitation, and earlier snowmelt, as well as changes to the frequency and duration of drought. These climate changes have and ...


Microtopoclimatic Effects On A Climate-Sensitive Habitat Specialist, The American Pika (Ochotona Princeps), Aidan Taylor Beers Jan 2016

Microtopoclimatic Effects On A Climate-Sensitive Habitat Specialist, The American Pika (Ochotona Princeps), Aidan Taylor Beers

Ecology & Evolutionary Biology Graduate Theses & Dissertations

There has been increasing acknowledgement that refugia at different scales facilitate the long-term survival of species and populations through climate oscillations. Species distributions and persistence are already affected by current climate change, and many taxa will become more spatially limited and less connected under further warming scenarios. Identifying likely microrefugia will improve our predictions of how species, communities, and ecosystems are likely to respond to climate change by providing a clearer understanding of likely demographic processes and connectivity. In this thesis, I considered suitable microhabitat in the face of current changing climates in the context of the persistence or development ...


Multi-Proxy Reconstructions Of Holocene Environmental Change And Catchment Biogeochemistry Using Algal Pigments And Stable Isotopes Preserved In Lake Sediment From Baffin Island And Iceland, Christopher Roth Florian Jan 2016

Multi-Proxy Reconstructions Of Holocene Environmental Change And Catchment Biogeochemistry Using Algal Pigments And Stable Isotopes Preserved In Lake Sediment From Baffin Island And Iceland, Christopher Roth Florian

Geological Sciences Graduate Theses & Dissertations

Lake sediments provide a continuous record of environmental change, integrating information about multiple biogeochemical processes occurring within the lake and catchment. Much of this is recorded by the chemical characteristics of sedimentary organic matter, which can be used as a proxy for past conditions. This dissertation examines Holocene lake sediment records from Baffin Island and Iceland, which, as a result of Arctic amplification feedbacks, are particularly sensitive to changes in climate. We integrated sedimentary algal pigments with more commonly used proxies such as stable isotopes, C:N ratio, and biogenic silica in order to derive a more complete understanding of ...


Predicting Suitable Habitat Decline Of Midwestern United States Amphibians And Quantifying The Consequence Of Declines Using Pond-Breeding Salamanders, Brock Struecker Jan 2016

Predicting Suitable Habitat Decline Of Midwestern United States Amphibians And Quantifying The Consequence Of Declines Using Pond-Breeding Salamanders, Brock Struecker

Master's Theses

With current declines of vertebrate taxa meeting or exceeding those of historic mass extinction events, there is a growing need to investigate the main drivers of declines. Amphibians are perhaps at greatest risk of global climate change and land-use changes than most other vertebrate classes and also have significant roles in ecosystem processes – combined, this creates a cause for concern. I designed a study that would investigate the effects of current and predicted climate change and land-use changes on amphibians using species distribution models and a field study to identify the potential consequences of amphibian species declines by investigating the ...


Re-Evaluating Climate As The Best Predictor Of Pika (Ochotona Princeps) Surface Activity, Maxwell C. Plichta Jan 2016

Re-Evaluating Climate As The Best Predictor Of Pika (Ochotona Princeps) Surface Activity, Maxwell C. Plichta

Undergraduate Honors Theses

Alpine and subalpine ecosystems are expected to experience a disproportionate amount of warming in the coming decades. Rising temperatures in these ecosystems threatens biodiversity and water resources globally. The American pika (Ochotona princeps) is a small mammal restricted to talus and rocky slopes often found above treeline. O. princeps has an acute sensitivity to high temperatures and utilizes microhabitats present in the talus to regulate body temperature. These attributes make pikas a bioindicator candidate for warming in the alpine. Monitoring and predicting pika persistence represents a potentially powerful tool to asses the current and future health of alpine ecosystems. Here ...


Assessing The Impacts Of Climate Change On The Surface Temperature Of Inland Lakes In Michigan, Kaitlin Reinl Jan 2016

Assessing The Impacts Of Climate Change On The Surface Temperature Of Inland Lakes In Michigan, Kaitlin Reinl

Dissertations, Master's Theses and Master's Reports

The aim of this study was to validate and apply a lake model for predicting the susceptibility of small inland lakes in Michigan to changes in thermal regime and increased cyanobacteria growth as a result of future climate conditions. The Freshwater Lake Model was selected, tested for sensitivity to various inputs, and validated through comparison to observed conditions. The sensitivity analysis showed that the lake model was most sensitive to solar radiation, air temperature, and air humidity. Comparison of predicted climate data with observed conditions revealed highly variable climate model error. The lake model validation was conducted using 10 lakes ...


Agricultural Labor In Midwestern United States Specialty Cropping Systems, Anna Liora Johnson Jan 2016

Agricultural Labor In Midwestern United States Specialty Cropping Systems, Anna Liora Johnson

Graduate Theses and Dissertations

Midwest specialty crop production is highly dependent on its workers, many of whom are immigrants. Growers are contending with changes in the composition and size of the farm worker labor force due in part to shifts in immigration patterns. They are also facing changes in weather patterns due to climate change. This research addresses how growers can manage the labor needs of their operations through these shifts. First, a vulnerability framework is applied to interviews with Michigan specialty crop growers on their experiences with variability of labor and weather in their specialty crop systems. This study finds that growers are ...


Fish Ladders Designed For Drop Culverts And Central Stoneroller Ecology Across A Latitudinal Gradient, John Arthur Lorenzen Jan 2016

Fish Ladders Designed For Drop Culverts And Central Stoneroller Ecology Across A Latitudinal Gradient, John Arthur Lorenzen

Electronic Theses and Dissertations

Stream connectivity is essential for the persistence of fish populations and maintenance of fish assemblage structure. Stream-road crossings can become barriers resulting in a loss of connectivity. Creating innovative tools for fisheries managers to allow fish passage through barrier stream-road crossings is important worldwide as climate change may force range shifts to stay within thermal requirements. Understanding how populations and metapopulations respond to climate is important as fisheries managers can use this information to make informed management decisions in regards to climate change and possible range shifts. Thus, we developed and tested a fish ladder to retrofit barrier stream-road crossings ...