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Climate change

2013

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Full-Text Articles in Life Sciences

Wood Decomposition In A Warmer World, Emily Elizabeth Austin Dec 2013

Wood Decomposition In A Warmer World, Emily Elizabeth Austin

Doctoral Dissertations

Climatic warming is altering species distributions and ecosystem functions across the globe. Wood is an important carbon pool and the fungal communities in wood are relatively simple compared to those in soil. These factors make decomposing wood an ideal system for exploring the influence of decomposer community on the response of decomposition to warming. My research has focused on the effects of warming wood decomposition rates and wood decomposing communities. Using field and lab- based manipulative experiments and field observations I explore the influence of tree species, wood decomposition stage, geography and warming on fungal community structure and activity. In ...


Assessing Growth Response To Climate Controls In A Great Basin Artemisia Tridentata Plant Community, Lorenzo F. Apodaca Dec 2013

Assessing Growth Response To Climate Controls In A Great Basin Artemisia Tridentata Plant Community, Lorenzo F. Apodaca

UNLV Theses, Dissertations, Professional Papers, and Capstones

An assessment of the growth response of key vegetative species to climatic variability is vital to identifying possible local impacts on ecosystems faced with imminent climate change. With current climate projections in Nevada predicting a shift to an even more arid climate with greater year-to-year variability, the imperative exists to identify the effects of specific climatic controls on plant growth and to research methods to assess large-scale vegetative changes, especially in more remote areas where readily available data sets may be lacking. This study utilized annual growth ring indices constructed from big sagebrush (Artemisia tridentatassp.tridentata) stems collected in Spring ...


Soil Freezing Effects On A Grass-Dominated Old Field Ecosystem Under Current And Future Rates Of Atmospheric Nitrogen Deposition, Mat Vankoughnett Nov 2013

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 ...


Thermal Adaptation Of Life History Traits In The Drosophila Melanogaster Group, Christopher James Austin Oct 2013

Thermal Adaptation Of Life History Traits In The Drosophila Melanogaster Group, Christopher James Austin

Electronic Thesis and Dissertation Repository

Thermal adaptation is typically detected by examining the tolerance to extreme temperatures in a few populations within a single life stage. However, the extent to which adaptation occurs among many different populations might depend on the tolerance of multiple life stages and the average temperature range that the population experiences. Here, I examined adaptation to local temperature conditions in four species of fruit flies, including a cosmopolitan species, Drosophila melanogaster, and three species with geographically small-sized ranges, D. nepalensis, D. sechellia, and D. mauritiana. The cosmopolitan species showed adaptation to native temperatures during the larval and adult life stages, but ...


Quantifying Crop Yield, Bioenergy Production And Greenhouse Gas Emissions From Cropland And Marginal Land Using A Model-Data Fusion Approach, Zhangcai Qin Oct 2013

Quantifying Crop Yield, Bioenergy Production And Greenhouse Gas Emissions From Cropland And Marginal Land Using A Model-Data Fusion Approach, Zhangcai Qin

Open Access Dissertations

Bioenergy is becoming increasingly attractive to many countries, but has sparked an intensive debate regarding energy, economy, society and environment. Biofuels provide alternative energy to conventional fossil fuels. However, the environmental impact of producing and using biofuel is a major concern to our society. This study is dedicated to quantifying and evaluating biofuel production and potential climate change mitigation due to potential large-scale bioenergy expansion in the conterminous United States, using model-data fusion approaches.

Biofuel made from conventional (e.g., maize (Zea mays L.)) and cellulosic crops (e.g., switchgrass (Panicum virgatum L.) and Miscanthus (Miscanthus × giganteus)) provides alternative energy ...


Microclimate Moderates Plant Responses To Macroclimate Warming, Pieter De Frenne, Francisco Rodríguez-Sánchez, David Anthony Coomes, Lander Baeten, Gorik Verstraeten, Mark Vellend, Markus Bernhardt-Römermann, Carissa D. Brownd, Jörg Brunet, Johnny Cornelis, Guillaume M. Decocq, Hartmut Dierschke, Ove Eriksson, Frank S. Gilliam, Radim Hédl, Thilo Heinken, Martin Hermy, Patrick Hommel, Michael A. Jenkins, Daniel L. Kelly, Keith J. Kirby, Fraser J. G. Mitchell, Tobias Naaf, Miles Newman, George Peterken, Petr Petrík, Jan Schultz, Grégory Sonnier, Hans Van Calster, Donald M. Waller, Gian-Reto Walther, Peter S. White, Kerry D. Woods, Monika Wulf, Bente Jessen Graae, Kris Verheyen Sep 2013

Microclimate Moderates Plant Responses To Macroclimate Warming, Pieter De Frenne, Francisco Rodríguez-Sánchez, David Anthony Coomes, Lander Baeten, Gorik Verstraeten, Mark Vellend, Markus Bernhardt-Römermann, Carissa D. Brownd, Jörg Brunet, Johnny Cornelis, Guillaume M. Decocq, Hartmut Dierschke, Ove Eriksson, Frank S. Gilliam, Radim Hédl, Thilo Heinken, Martin Hermy, Patrick Hommel, Michael A. Jenkins, Daniel L. Kelly, Keith J. Kirby, Fraser J. G. Mitchell, Tobias Naaf, Miles Newman, George Peterken, Petr Petrík, Jan Schultz, Grégory Sonnier, Hans Van Calster, Donald M. Waller, Gian-Reto Walther, Peter S. White, Kerry D. Woods, Monika Wulf, Bente Jessen Graae, Kris Verheyen

Biological Sciences Faculty Research

Recent global warming is acting across marine, freshwater, and terrestrial ecosystems to favor species adapted to warmer conditions and/or reduce the abundance of cold-adapted organisms (i.e., “thermophilization” of communities). Lack of community responses to increased temperature, however, has also been reported for several taxa and regions, suggesting that “climatic lags” may be frequent. Here we show that microclimatic effects brought about by forest canopy closure can buffer biotic responses to macroclimate warming, thus explaining an apparent climatic lag. Using data from 1,409 vegetation plots in European and North American temperate forests, each surveyed at least twice over ...


Four Decades Of Andean Timberline Migration And Implications For Biodiversity Loss With Climate Change, David A. Lutz, Rebecca L. Powell, Miles R. Silman Sep 2013

Four Decades Of Andean Timberline Migration And Implications For Biodiversity Loss With Climate Change, David A. Lutz, Rebecca L. Powell, Miles R. Silman

Open Dartmouth: Published works by Dartmouth faculty

Rapid 21st-century climate change may lead to large population decreases and extinction in tropical montane cloud forest species in the Andes. While prior research has focused on species migrations per se, ecotones may respond to different environmental factors than species. Even if species can migrate in response to climate change, if ecotones do not they can function as hard barriers to species migrations, making ecotone migrations central to understanding species persistence under scenarios of climate change. We examined a 42-year span of aerial photographs and high resolution satellite imagery to calculate migration rates of timberline–the grassland-forest ecotone–inside and ...


Evidence For 20th Century Climate Warming And Wetland Drying In The North American Prairie Pothole Region, Brett A. Werner, W. Carter Johnson, Glenn R. Guntenspergen Sep 2013

Evidence For 20th Century Climate Warming And Wetland Drying In The North American Prairie Pothole Region, Brett A. Werner, W. Carter Johnson, Glenn R. Guntenspergen

Natural Resource Management Faculty Publications

The Prairie Pothole Region (PPR) of North America is a globally important resource that provides abundant and valuable ecosystem goods and services in the form of biodiversity, groundwater recharge, water purification, flood attenuation, and water and forage for agriculture. Numerous studies have found these wetlands, which number in the millions, to be highly sensitive to climate variability. Here, we compare wetland conditions between two 30-year periods (1946–1975; 1976–2005) using a hindcast simulation approach to determine if recent climate warming in the region has already resulted in changes in wetland condition. Simulations using the WETLANDSCAPE model show that 20th ...


Evaluation Of Species Distribution Models By Resampling Of Sites Surveyed A Century Ago By Joseph Grinnell, Adam B. Smith, Maria J. Santos, Michelle S. Koo, Karen M.C. Rowe, Kevin C. Rowe, James L. Patton, John D. Perrine, Steven R. Beissinger, Craig Moritz Sep 2013

Evaluation Of Species Distribution Models By Resampling Of Sites Surveyed A Century Ago By Joseph Grinnell, Adam B. Smith, Maria J. Santos, Michelle S. Koo, Karen M.C. Rowe, Kevin C. Rowe, James L. Patton, John D. Perrine, Steven R. Beissinger, Craig Moritz

Biological Sciences

Species distribution models (SDMs) are commonly applied to predict species’ responses to anticipated global change, but lack of data from future time periods precludes assessment of their reliability. Instead, performance against test data in the same era is assumed to correlate with accuracy in the future. Moreover, high-confidence absence data is required for testing model accuracy but is often unavailable since a species may be present when undetected. Here we evaluate the performance of eight SDMs trained with historic (1900–1939) or modern (1970–2009) climate data and occurrence records for 18 mammalian species. Models were projected to the same ...


Collaborative Research: Globec Pan-Regional Synthesis: End-To-End Energy Budgets In Us-Globec Regions, Andrew C. Thomas Aug 2013

Collaborative Research: Globec Pan-Regional Synthesis: End-To-End Energy Budgets In Us-Globec Regions, Andrew C. Thomas

University of Maine Office of Research Administration: Grant Reports

The research addresses the overarching question: are marine food webs leading to fisheries controlled from the top-down, the bottom up, or a combination of the two? To address this question we will (1) compare end-to-end energy budgets of the 4 US-GLOBEC study regions in the context of top-down v. bottom-up forcing, (2) assess the skills of the regional models in capturing basic material fluxes, (3) extract diagnostics from the regional models that will be used to evaluate the effects of climate change and fishing pressure across GLOBEC regions and (4) develop quantitative methods to compare the diagnostics. The major successes ...


Warming Winters And Changing Habitats: Interactive Effects On Raptor Populations And Implications For Conservation, Neil A. Paprocki Aug 2013

Warming Winters And Changing Habitats: Interactive Effects On Raptor Populations And Implications For Conservation, Neil A. Paprocki

Boise State University Theses and Dissertations

Studies across multiple spatial and temporal scales will improve understanding of the drivers of global change including habitat degradation, invasive species, and climate change. How global drivers affect the ecology of wintering raptors in western North America and the Great Basin may have important implications for changes in distribution and abundance, and consequently population persistence. I examined the winter distributions of six western North America raptor species using Christmas Bird Count data from 1975-2011 to assess range shifts over time and in relation to temperature. Also, I considered whether population patterns within Bird Conservation Regions (BCR) were best explained by ...


Local Adaptation To Climate Change In A Calcareous Grassland System, Catherine Ravenscroft Aug 2013

Local Adaptation To Climate Change In A Calcareous Grassland System, Catherine Ravenscroft

Biology - Dissertations

Annual manipulations of temperature and rainfall have been maintained in intact calcareous grassland since 1993 at the Buxton Climate Change Impacts Laboratory (BCCIL) in northern England (UK). Here I investigated the role of local adaptation as mechanism of the apparent resistance of species' to long-term climate manipulations at BCCIL using a common forb, Plantago lanceolata. Plantago lanceolata is a rosette-forming, perennial herb of wide-ranging distribution, and one of the more common forbs in calcareous grasslands, including BCCIL. In the first study I used a common garden approach to test for evidence of selection for different suites of functional traits in ...


Agriculture In A Water Scarce World, Allison Roberts, Amjad Assi, Bassel Daher, Men Li Jun 2013

Agriculture In A Water Scarce World, Allison Roberts, Amjad Assi, Bassel Daher, Men Li

Student Papers in Public Policy

According to the McKinsey report (2009), the world is facing a water scarcity challenge where agriculture is its predominant consumer. It accounts for approximately 3100 billion m3, or 71 percent of global water withdrawals today, and is expected to increase to 4500 billion m3 by 2030. This increase is due to a number of factors: growing population and the ever growing necessity to cater for its food needs, economic growth, the variability of precipitation trends and increase in global temperatures. In addition to the increase in water scarcity, the agricultural sector faces an enormous challenge of producing almost ...


Marine Invertebrates: Communities At Risk, Jennifer A. Mather Jun 2013

Marine Invertebrates: Communities At Risk, Jennifer A. Mather

Ecological Impacts of Climate Change Collection

Our definition of the word ‘animal’ centers on vertebrates, yet 99% of the animals on the planet are invertebrates, about which we know little. In addition, although the Census of Marine Life (COML.org) has recently conducted an extensive audit of marine ecosystems, we still do not understand much about the animals of the seas. Surveys of the best-known ecosystems, in which invertebrate populations often play a key role, show that the invertebrate populations are affected by human impact. Coral animals are the foundation of coral reef systems, which are estimated to contain 30% of the species in the ocean ...


Fisheries Management In A Changing Climate: Lessons From The 2012 Ocean Heat Wave In The Northwest Atlantic., Katherine E. Mills, Andrew Pershing, Curtis J. Brown, Yong Chen, Fu-Sung Chiang, Daniel S. Holland, Sigrid Lehuta, Janet A. Nye, Jenny C. Sun, Andrew C. Thomas, Richard A. Wahle Jun 2013

Fisheries Management In A Changing Climate: Lessons From The 2012 Ocean Heat Wave In The Northwest Atlantic., Katherine E. Mills, Andrew Pershing, Curtis J. Brown, Yong Chen, Fu-Sung Chiang, Daniel S. Holland, Sigrid Lehuta, Janet A. Nye, Jenny C. Sun, Andrew C. Thomas, Richard A. Wahle

Publications

No abstract provided.


Assessing Physiological Thresholds For Eelgrass (Zostera Marina L.) Survival In The Face Of Climate Change, Carolyn Jane Ewers Jun 2013

Assessing Physiological Thresholds For Eelgrass (Zostera Marina L.) Survival In The Face Of Climate Change, Carolyn Jane Ewers

Master's Theses

Seagrasses are well known for the important ecological roles they play in coastal marine waters worldwide. However, the severe rate of decline observed in seagrasses this century is expected to accelerate with climate change. Conservation efforts can be improved by quantifying physiological thresholds of seagrasses and using these estimates in modeling to forecast changes in distribution. This study examines the response of eelgrass (Zostera marina L.) across current temperatures to look for early warning signs of vulnerability and to evaluate the ways we determine critical thresholds for survival. Whole eelgrass ramets, collected from three beds in Morro Bay, California, were ...


Ant Community Dynamics And The Effects Of Global Warming, Katharine Lisa Stuble May 2013

Ant Community Dynamics And The Effects Of Global Warming, Katharine Lisa Stuble

Doctoral Dissertations

This dissertation seeks to provide an understanding of how species coexist and, further, how climate change may alter communities by acting on the mechanisms that promote coexistence. Specifically, I examined coexistence among ant species in eastern deciduous forests and the effects that warming may have on foraging activity. Through a series of field observations, I sought evidence for the importance of four of the most commonly cited mechanisms for coexistence among ant species: the dominance – discovery tradeoff, the dominance – thermal tolerance tradeoff, spatial segregation, and niche partitioning. In this system, I did not find evidence for any of these mechanisms ...


Final Evaluation Of The North East Agricultural Region (Near) Strategy, Andrew Blake, Don Burnside, Vicki Williams May 2013

Final Evaluation Of The North East Agricultural Region (Near) Strategy, Andrew Blake, Don Burnside, Vicki Williams

All other publications

No abstract provided.


Modeling Usa Stream Temperatures For Stream Biodiversity And Climate Change Assessments, Ryan A. Hill May 2013

Modeling Usa Stream Temperatures For Stream Biodiversity And Climate Change Assessments, Ryan A. Hill

All Graduate Theses and Dissertations

Stream temperature (ST) is a primary determinant of individual stream species distributions and community composition. Moreover, thermal modifications associated with urbanization, agriculture, reservoirs, and climate change can significantly alter stream ecosystem structure and function. Despite its importance, we lack ST measurements for the vast majority of USA streams. To effectively manage these important systems, we need to understand how STs vary geographically, what the natural (reference) thermal condition of altered streams was, and how STs will respond to climate change. Empirical ST models, if calibrated with physically meaningful predictors, could provide this information. My dissertation objectives were to: (1) develop ...


Colorado River Cutthroat Habitat Resistance And Resilience To Climate Change, Kate Olsen May 2013

Colorado River Cutthroat Habitat Resistance And Resilience To Climate Change, Kate Olsen

All Graduate Theses and Dissertations

Colorado River cutthroat trout, Oncorhyncus clarki pleuriticus , occupy less than 12% of their historic range. Restoration and conservation of this species are currently under way across the upper Colorado River basin, but guidance to inform management decisions related to the impacts of climate change on cutthroat is lacking. Shifts in the thermal distribution of freshwater fish have been documented, and will continue to occur as cold water habitat is threatened by warming water temperatures. Coupled air and water temperature data allow for an estimation of potential resistance and resilience to warming, determining the effect that local air has on stream ...


Climate Change Extension: Presenting The Science Is Necessary But Insufficient, Paul C. Vincelli, Rebecca L. Mcculley Apr 2013

Climate Change Extension: Presenting The Science Is Necessary But Insufficient, Paul C. Vincelli, Rebecca L. Mcculley

Plant Pathology Presentations

Why Should We Consider How to Present Scientific Information?

To engage a wide spectrum of agricultural producers in the discussion of human-induced climate change and its mitigation.

What Did We Do?

Our initial Extension efforts on climate change in Kentucky were based on an information-deficit model, which assumes that citizens fail to accept climate change because they don’t understand the science. However, social science research indicates that this topic has cultural significance for many agricultural producers, suggesting that presentation of sound scientific information alone is likely to be unpersuasive. Based on social science research, we redesigned our outreach efforts ...


Bears, Birds, Bugs And Climate: Environews #^, Richard Philp Mar 2013

Bears, Birds, Bugs And Climate: Environews #^, Richard Philp

Richard B. Philp

There has long been a concern that global warming would cause species movements reflective of the instinctive drive to seek the most favorable environmental conditions. One concern is that agricultural pests and carriers of diseases like malaria would move north and south from tropical and subtropical areas. Some changes may benefit the species but not necessarily humankind. Both predicted and observed changes are discussed with examples from plant and animal species. Some concerns are controversial, kike the effect of climate change on polar bears.


Climate Change Adaptation Chapter: Marshfield, Massachusetts, Joshua H. Chase, Jonathan G. Cooper, Rory Elizabeth Fitzgerald, Filipe Antunes Lima, Sally R. Miller, Toni Marie Pignatelli Feb 2013

Climate Change Adaptation Chapter: Marshfield, Massachusetts, Joshua H. Chase, Jonathan G. Cooper, Rory Elizabeth Fitzgerald, Filipe Antunes Lima, Sally R. Miller, Toni Marie Pignatelli

Sally Miller

Climate change, understood as a statistically significant variation in the mean state of the climate or its variability, is the greatest environmental challenge of this generation (Intergovernmental Panel on Climate Change, 2001). Marshfield is already being affected by changes in the climate that will have a profound effect on the town’s economy, public health, coastal resources, natural features, water systems, and public and private infrastructure. Adaptation strategies have been widely recognized as playing an important role in improving a community’s ability to respond to climate stressors by resisting damage and recovering quickly. Based on review of climate projections ...


Ecology And Conservation Of The Montane Forest Avian Community In Northeastern North America, William V. Deluca Feb 2013

Ecology And Conservation Of The Montane Forest Avian Community In Northeastern North America, William V. Deluca

Open Access Dissertations

Montane forests provide habitat for unique assemblages of flora and fauna that contribute significantly to a region’s biodiversity. Previous work indicates that montane forest ecosystems are exceedingly vulnerable to a host of anthropogenic stressors including climate change, atmospheric deposition, and recreation, to name a few. Montane forests and other high elevation ecosystems are considered to be among the first and most severely impacted by climate change. It is therefore, imperative to evaluate anthropogenic impacts on montane ecosystems and maintain reliable monitoring methods that are capable of tracking potential shifts in the distribution of species dependent on these systems. I ...


Assessment Matrix Based Evaluation Of Ecosystem Services In Relation To Land Use Change Scenarios, Gergő Gábor Nagy, Veronika Magyar, Sándor Jombach, László Kollányi, Balázs Duray Jan 2013

Assessment Matrix Based Evaluation Of Ecosystem Services In Relation To Land Use Change Scenarios, Gergő Gábor Nagy, Veronika Magyar, Sándor Jombach, László Kollányi, Balázs Duray

Proceedings of the Fábos Conference on Landscape and Greenway Planning

The ecosystem services are natural assets and services, which are used by humans directly or indirectly over their respective lifetimes (MEA, 2005). Several authors and organizations describe these goods of nature in different ways. Some authors use ecological concepts as the basis for categorization (Norberg, 1999), others concentrate on different human needs (Wallace, 2007), however the most common categories are based on some functional distinction (MEA, 2005; de Groot, 2006; Hein et al., 2006). Authors representing this latter group usually mention the following classification: provisioning, regulating, supporting and cultural services. The provisioning services like water, wood or timber are used ...


Effects Of Detention For Flooding Mitigation Under Climate Change Scenarios— Implication For Landscape Planning In The Charles River Watershed, Massachusetts, Usa, Chingwen Cheng, Elizabeth A. Brabec, Yi-Chen E. Yang, Robert L. Ryan Jan 2013

Effects Of Detention For Flooding Mitigation Under Climate Change Scenarios— Implication For Landscape Planning In The Charles River Watershed, Massachusetts, Usa, Chingwen Cheng, Elizabeth A. Brabec, Yi-Chen E. Yang, Robert L. Ryan

Proceedings of the Fábos Conference on Landscape and Greenway Planning

Climate change has posed increased risks to environmental hazards (e.g., flooding, droughts, hurricanes) in addition to new challenges under climate change impacts (e.g., early snow melt, sea level rises, heat waves). Floods are omnipresent in almost every city in the United States and account for the most economic losses than any other single geophysical hazard (White and Haas 1975). Previous climate change studies have suggested promising trends of increasing temperature and changing precipitation patterns as well as increased intensity and duration of storm events that are likely to result in more flooding events in the Northeast region. Flooding ...


Phylogeography Of Eastern Leatherwood (Dirca Palustris L.) Resolved By Chloroplast Sequencing And Microsatellite Genotyping, Bryan James Peterson Jan 2013

Phylogeography Of Eastern Leatherwood (Dirca Palustris L.) Resolved By Chloroplast Sequencing And Microsatellite Genotyping, Bryan James Peterson

Graduate Theses and Dissertations

The broad distribution of eastern leatherwood (Dirca palustris L.), from Florida to Canada, contrasted with its patchy restriction to rich, mesic forests and the paucity of vectors for dispersal of its seeds, represents a classic example of Reid's paradox of plant migration. It long has been presumed that temperate forest species of eastern North America persisted in southern glacial refugia near the Gulf Coast, after which many dispersed nearly 2000 km to contemporary northern range limits. The rates of migration necessary to account for present distributions exceed those suggested by contemporary observations of seed dispersal. I used ecological niche ...


Ecological Interactions Influencing Avicennia Germinans Propagule Dispersal And Seedling Establishment At Mangrove-Saltmarsh Boundaries, Jennifer Mcclain Peterson Jan 2013

Ecological Interactions Influencing Avicennia Germinans Propagule Dispersal And Seedling Establishment At Mangrove-Saltmarsh Boundaries, Jennifer Mcclain Peterson

Graduate Theses and Dissertations

Mangroves and saltmarshes are ecologically important coastal ecosystems; unfortunately, these low-lying coastal ecosystems are vulnerable to global climate change. As sea-levels rise, mangroves are expected to shift their distribution landward towards higher elevation sites that are occupied by other plants, including saltmarsh taxa. Therefore, mangrove recruits at the leading edge of expansion may interact with diverse assemblages of saltmarsh plants, and these interactions could influence the success of mangrove encroachment into higher tidal-elevation areas. The purpose of the research presented here was to investigate empirically the ecological interactions that may influence the recruitment of the black mangrove, Avicennia germinans, into ...


Changes In Net Ecosystem Production Over The Past 40 Years In Arctic Tundra Ponds Near Barrow, Alaska: Application Of Historic And Modern Techniques, Nickole Ann Miller Jan 2013

Changes In Net Ecosystem Production Over The Past 40 Years In Arctic Tundra Ponds Near Barrow, Alaska: Application Of Historic And Modern Techniques, Nickole Ann Miller

Open Access Theses & Dissertations

Arctic environments have gained interest recently due to their sensitivity to climate change. As warming has created longer growing seasons, extended ice-free periods as well as permafrost thaw, the production in freshwater ecosystems has the potential to be greatly impacted. It is hypothesized that as climate change and warming occurs, increases in primary production will occur and ponds will become carbon sinks. Net ecosystem production (NEP) was determined using phytoplankton and periphyton samples collected weekly during the growing season (June - August) from arctic tundra ponds near Barrow, Alaska. Enrichment with 14C was used to determine both weekly photosynthetic rates and ...


Relating Climate Change To The Nesting Phenology And Nest Environment Of Marine Turtles, Monette Schwoerer Jan 2013

Relating Climate Change To The Nesting Phenology And Nest Environment Of Marine Turtles, Monette Schwoerer

Electronic Theses and Dissertations, 2004-2019

Ectotherms (including marine turtles) being especially sensitive to climate, are at risk to the accelerated rate of human-driven climate change. This study addresses two concerns associated with marine turtles and climate change – the relationship between the timing of marine turtle nesting and sea surface temperature; and the concern over the feminization of marine turtle populations due to rising sand temperatures. Previous studies of loggerhead sea turtles (Caretta caretta) and green sea turtles (Chelonia mydas) have documented the relationship between sea surface temperatures and nesting phenology. Earlier nesting behaviors in both species have been associated with warmer sea surface temperatures. Also ...