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Marine Population Connectivity: Range Boundaries And Climate Change, Rhiannon Leigh Rognstad

Theses and Dissertations

Population connectivity, particularly in open systems, is an important metric for understanding population-level processes on both ecological and evolutionary timescales. In coastal marine systems, adults are typically sedentary and dispersal occurs primarily during a larval stage when individuals are transported in ocean currents. Because coastal marine populations exist as networks of interconnected subpopulations, variation in the magnitude and extent of population connectivity can have profound effects on population dynamics and species distribution limits. Connectivity is a complex process, affected by a multitude of factors, including adult inputs and physical dispersal, which operate at multiple scales and may interact. This dissertation …

Thermal Ecology And Physiology Of An Intertidal Predator-Prey System: Pisaster Ochraceus And Mytilus Californianus, Cristian J. Monaco

Theses and Dissertations

Untangling natural systems’ complexity requires understanding the mechanisms responsible for organisms’ responses to environmental change. Recently, significant advances have been made by recognizing the relevance of direct and indirect effects, which take place when multiple biotic and abiotic factors influence each other. I examined potential direct effects of environmental variables on a predator-prey interaction, as well as potential indirect effects of these variables on the interaction itself. I placed emphasis on behavioral and physiological adaptations, which would potentially contribute/modify these effects. My study system was comprised of a rocky intertidal keystone predator, the sea star Pisaster ochraceus, and its main …

The Impact Of Changing Surface Ocean Conditions On The Dissolution Of Aerosol Iron, Matthew Fishwick, Peter Sedwick, Maeve Lohan, Pau Worsfold, Kristen N. Buck, Thomas Church, Simon Ussher

Marine Science Faculty Publications

The proportion of aerosol iron (Fe) that dissolves in seawater varies greatly and is dependent on aerosol composition and the physicochemical conditions of seawater, which may change depending on location or be altered by global environmental change. Aerosol and surface seawater samples were collected in the Sargasso Sea and used to investigate the impact of these changing conditions on aerosol Fe dissolution in seawater. Our data show that seawater temperature, pH, and oxygen concentration, within the range of current and projected future values, had no significant effect on the dissolution of aerosol Fe. However, the source and composition of aerosols …

Framing A “Wicked” Debate: Subsistence, Nutrition, And Indigenous Rights Versus Deforestation, Air Pollution, And Climate Change, Cynthia Fowler

Faculty Scholarship

This presentation considers anthropogenic environmental change as a wicked problem in which multiple, divergent understandings of complex systems and changing conditions coexist. The stakes are high with this wicked problem for the whole Earth and all of humanity. Stakes are especially high in the tropical agropastoral communities whose resource management systems are the subject of much consternation and, at the same time, whose systems are incompletely known.

Cold Hardiness And Deacclimation Of Overwintering Papilio Zelicaon Pupae, Caroline M. Williams, Nicolai Annegret, Brent J. Sinclair, Laura V. Ferguson, Mark A. Bernards, Jessica J. Hellmann

Biology Publications

Seasonally-acquired cold tolerance can be reversed at warm temperatures, leaving temperate ectotherms vulnerable to cold snaps. However, deacclimation, and its underlying mechanisms, has not been well-explored in insects. Swallowtail butterflies are widely distributed but in some cases their range is limited by low temperature and their cold tolerance is seasonally acquired, implying that they experience mortality resulting from deacclimation. We investigated cold tolerance and hemolymph composition of Anise swallowtail (Papilio zelicaon) pupae during overwintering in the laboratory, and after four days exposure to warm temperatures in spring. Overwintering pupae had supercooling points around − 20.5 °C and survived …

The Influence Of Drought On The Ecological And Evolutionary Genomics Of Fungal Pathogenesis In An Annual Plant, Brassica Rapa, Niamh Breda O'Hara

Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions)

There is growing evidence that populations are evolving rapidly in response to climate change. However, the potential cost associated with adapting, and the genetic basis of both rapid evolution and costs of adaptation remain largely unexplored. With climate change, drought is increasing in frequency and severity, widely affecting plant yield and fitness in agricultural and natural populations. For my dissertation, I integrated multiple approaches (field, greenhouse, lab and bioinformatic) to explore the ecological and evolutionary effects of drought on an agriculturally important plant-pathogen system: the annual herbaceous plant Brassica rapa (field mustard), and its fungal pathogen Alternaria brassicae. In a …

Community Ecology, Climate Change And Ecohydrology In Desert Grassland And Shrubland, Matthew Daniel Petrie

Biology ETDs

This dissertation explores the climate, ecology and hydrology of Chihuahuan Desert ecosystems in the context of global climate change. In coming decades, the southwestern United States is projected to experience greater temperature-driven aridity, possible small decreases in annual precipitation, and a later onset of summer monsoon rainfall. These changes may have profound consequences for ecological systems in the Chihuahuan Desert, which are intensely water-limited and respond to even small pulses of moisture availability. The first chapter (Chapter 2) compares change in the properties of monsoon season precipitation from 1910-2010 in the northern Chihuahuan Desert region to local variability in monsoon …

Small Mammals Matter? Linking Plant Invasion, Biotic Resistance, And Climate Change In Post-Fire Plant Communities, Rory Charles O'Connor

Theses and Dissertations

The introduction and establishment of exotic species can profoundly alter ecosystems. Two exotic species drastically changing the landscape of deserts in western North America are Bromus tectorum L. and Bromus rubens L. Through the buildup of biomass and slow decomposition rates in deserts these two exotic annual grasses can alter fire regimes that change the plant and animal community dynamics in the ecosystems. To better understand the ecological mechanisms that could restrict or alter the patterns of invasive plant establishment we established a replicated full factorial experiment in the Great Basin and Mojave Desert. The combinations of factors being manipulated …

Planning For Adaptation To Climate Change: Lessons From The Us National Wildlife Refuge System, Robert L. Fischman, Vicky J. Meretsky, Alexei Babko, Michael Kennedy, Lei Liu, Michelle Robinson

Articles by Maurer Faculty

US national wildlife refuges have recent, detailed management plans illustrating the state of planning for climate-change adaptation in protected areas. Discussion of and prescriptions for addressing climate change increased in refuge plans between 2005 and 2010 but decreased in 2011. The plans respond to some climate-change impacts on biodiversity and call for monitoring but with little clarity regarding how to act on monitoring results and scant attention to future changes in phenology and community composition. The threats posed by sea-level rise generated the best-developed plan prescriptions. Examples of excellent prescriptions provide models for future planning. Some decision-support tools, such as …

Warming Reduces Tall Fescue Abundance But Stimulates Toxic Alkaloid Concentrations In Transition Zone Pastures Of The U.S., Rebecca L. Mcculley, Lowell P. Bush, Anna E. Carlisle, Huihua Ji, Jim A. Nelson

Plant and Soil Sciences Faculty Publications

Tall fescue pastures cover extensive acreage in the eastern half of the United States and contribute to important ecosystem services, including the provisioning of forage for grazing livestock. Yet little is known concerning how these pastures will respond to climate change. Tall fescue's ability to persist and provide forage under a warmer and wetter environment, as is predicted for much of this region as a result of climate change, will likely depend on a symbiotic relationship the plant can form with the fungal endophyte, Epichloë coenophiala. While this symbiosis can confer environmental stress tolerance to the plant, the endophyte …

Collapse Of An Ecological Network In Ancient Egypt, Justin Yeakel, Mathias Pires, Lars Rudolf, Nathaniel Dominy

Dartmouth Scholarship

The dynamics of ecosystem collapse are fundamental to determining how and why biological communities change through time, as well as the potential effects of extinctions on ecosystems. Here, we integrate depictions of mammals from Egyptian antiquity with direct lines of paleontological and archeological evidence to infer local extinctions and community dynamics over a 6,000-y span. The unprecedented temporal resolution of this dataset enables examination of how the tandem effects of human population growth and climate change can disrupt mammalian communities. We show that the extinctions of mammals in Egypt were nonrandom and that destabilizing changes in community composition coincided with …

Breeding Time In A Migratory Songbird Is Predicted By Drought Severity And Group Size, Charles R. Brown, Mary Bomberger Brown

School of Natural Resources: Faculty Publications

Global climate change is altering the breeding phenology of many organisms, and one reported consequence of warmer average temperatures is earlier breeding times in migratory songbirds of north temperate latitudes. Less studied are the potential interactions between earlier breeding and social behavior in colonial species. We investigated how breeding time, as measured by colony initiation dates across the entire summer, in Cliff Swallows (Petrochelidon pyrrhonota) of southwestern Nebraska, USA, changed over a 30-year period and could be predicted by climatic variables, year, and colony size. Mean colony initiation date became earlier over the study, with variation best predicted …

Acclimation Of Photosynthetic Temperature Optima Of Temperate And Boreal Tree Species In Response To Experimental Forest Warming, Kerrie M. Sendall, Peter B. Reich, Changming Zhao, Hou Jihua, Xia Orong Wei, Artur Stefanski, Karen Rice, Roy L. Rich, Rebecca A. Montgomery

Faculty Research & Creative Activity

Rising temperatures caused by climate change could negatively alter plant ecosystems if temperatures exceed optimal

temperatures for carbon gain. Such changes may threaten temperature-sensitive species, causing local extinctions and

range migrations. This study examined the optimal temperature of net photosynthesis (Topt) of two boreal and four

temperate deciduous tree species grown in the field in northern Minnesota, United States under two contrasting temperature

regimes. We hypothesized that Topt would be higher in temperate than co-occurring boreal species, with

temperate species exhibiting greater plasticity in Topt, resulting in better acclimation to elevated temperatures. The

chamberless experiment, located at two sites in …

Delinking International Environmental Law & Climate Change, Cinnamon Carlarne

Michigan Journal of Environmental & Administrative Law

This Article challenges the existing paradigm in international law that frames global efforts to address climate change as a problem of and for international environmental law. The most recent climate reports tell us that warming is unequivocal and that we are already experiencing the impacts of climate change at the domestic level in the United States. Against this backdrop, much has been written recently in the United States about domestic efforts to address climate change. These efforts are important, but they leave open the question of how the global community can work together to address the greatest collective action problem …

Warming, Competition, And Bromus Tectorum Population Growth Across An Elevation Gradient, Aldo Compagnoni, Peter B. Adler

Green Canyon Environmental Research Area, Logan Utah

Cheatgrass (Bromus tectorum) is one of the most problematic invasive plant species in North America and climate change threatens to exacerbate its impacts. We conducted a two‐year field experiment to test the effect of warming, competition, and seed source on cheatgrass performance across an elevation gradient in northern Utah. We hypothesized that warming would increase cheatgrass performance, but that warming effects would be limited by competing vegetation and by local adaptation of cheatgrass seed sources. The warming treatment relied on open top chambers, we removed vegetation to assess the effect of competition from neighboring vegetation, and we reciprocally …

Natural Selection On Thermal Performance In A Novel Thermal Environment, Michael L. Logan, Robert M. Cox, Ryan Calsbeek

Dartmouth Scholarship

Tropical ectotherms are thought to be especially vulnerable to climate change because they are adapted to relatively stable temperature regimes, such that even small increases in environmental temperature may lead to large decreases in physiological performance. One way in which tropical organisms may mitigate the detrimental effects of warming is through evolutionary change in thermal physiology. The speed and magnitude of this response depend, in part, on the strength of climate-driven selection. However, many ectotherms use behavioral adjustments to maintain preferred body temperatures in the face of environmental variation. These behaviors may shelter individuals from natural selection, preventing evolutionary adaptation …

Limited Alpine Climatic Warming And Modeled Phenology Advancement For Three Alpine Species In The Northeast United States, Michael L. Davis, Kenneth D. Kimball, Douglas M. Weihrauch, Georgia L. D. Murray, Kenneth Rancourt

Ecology Center Publications

• Premise of the study: Most alpine plants in the Northeast United States are perennial and flower early in the growing season, extending their limitedgrowing season. Concurrently, they risk the loss of reproductive efforts to late frosts. Quantifying long-term trends in northeastern alpine flower phenology and late-spring/early-summer frost risk is limited by a dearth of phenology and climate data, except for Mount Washington, New Hampshire (1916 m a.s.l.).
• Methods: Logistic phenology models for three northeastern US alpinespecies (Diapensia lapponica, Carex bigelowii and Vaccinium vitis-idaea) were developed from 4 yr (2008–2011) of phenology and air temperature measurements from 12 …

Assessing Climate Variability Effects On Dengue Incidence In San Juan, Puerto Rico, Pablo Méndez-Lázaro, Frank E. Muller-Karger, Daniel Otis, Matthew J Mccarthy, Marisol Peña-Orellana

Marine Science Faculty Publications

We test the hypothesis that climate and environmental conditions are becoming favorable for dengue transmission in San Juan, Puerto Rico. Sea Level Pressure (SLP), Mean Sea Level (MSL), Wind, Sea Surface Temperature (SST), Air Surface Temperature (AST), Rainfall, and confirmed dengue cases were analyzed. We evaluated the dengue incidence and environmental data with Principal Component Analysis, Pearson correlation coefficient, Mann-Kendall trend test and logistic regressions. Results indicated that dry days are increasing and wet days are decreasing. MSL is increasing, posing higher risk of dengue as the perimeter of the San Juan Bay estuary expands and shorelines move inland. Warming …

Full Of Hot Air: Why The Atmospheric Trust Litigation Theory Is An Unworkable Attempt To Expand The Public Trust Doctrine Beyond Its Common Law Foundations, Andrew Ballentine

Student Works

The issue of climate change has been a major feature in public discourse for more than twenty-five years and the debate has vociferously engaged scientists, politicians, and the general public. Climate change is impacting the local, state, national and global levels,ranging from the loss of coastal land in Massachusetts to the loss of permafrost in Alaska. The challenge to addressing the crisis that these climate change impacts are presenting has inspired various proposals, both legal and scientific. The 2012 case Alec L.v. Jackson has brought the issue of Atmospheric Trust Litigation and potential claims for injury due to climate change …

A Threat To New Zealand's Tuatara Heats Up, Kristine L. Grayson, Nicola J. Mitchell, Nicola J. Nelson

Biology Faculty Publications

No matter how many times we head to one of New Zealand's offshore islands, the feelings are always a mix of sheer awe at the beauty and biodiversity preserved in these special refuges and lingering nerves. Did we remember all the gear? Do we have enough food and water in case we get stuck? Can the helicopter land on the side of a cliff in these winds? These epic journeys are in pursuit of a lone remnant of the reptile evolutionary tree, with a unique ecology that has big implications under climate change.

Manipulation Of Larval And Winter Habitat Reveals Potential Effects Of Urbanization And Climate Change On Wood Frogs In Connecticut, Jason H. O'Connor

Master's Theses

Human activity can result in both local and global changes in the environment which in turn can affect other organisms and may result in population declines and loss of biodiversity. At the local scale, human activity often causes changes in habitat quality. For example, development and agriculture increase water turbidity which can influence wetland communities. At a global scale, carbon emissions are altering Earth’s climate, leading to increasing air temperatures. Using Wood Frogs, Lithobates sylvaticus, a wide-ranging, pond breeding amphibian, I sought to determine how sediment input affects larval amphibians and to assess how predicted loss of snow cover …

Effect Of Increased Water Temperature On Warm Water Fish Feeding Behavior And Habitat Use, Eric Walberg

Journal of Undergraduate Research at Minnesota State University, Mankato

Global warming could cause changes in species behavior and life history. Stream fish may be significantly affected by climate change because individuals are restricted in their movements by water systems and other physical factors, preventing migration to locations more thermally suitable. The effect of warmer waters on stream fish could change behavior and affect the fish species survival and ultimately ecosystem function. During my experiment I observed the effects of increased water temperature on the feeding behavior and habitat use of two native Minnesota fish species, black crappie (Pomoxis nigromaculatus) and black bullhead (Ameiurus melas). An increase of 2oC over …

Environment Stress And Increased Vulnerability To Impoverishment In Rural Ethiopia: Case Studies Evidence, Tesfaye Teklu

International Journal of African Development

Integral to the global trends in climate change, there are slow but notable long-term changes in level of weather (e.g. slow increase in temperature and decline in rainfall) accompanied with increased weather extremes such as increased frequency and intensity of drought in Ethiopia. These changes are occurring over large geographical area including the most populous and arable highlands. Rural households in these environmentally stressed areas employ multiple strategies to manage environmental risk. However, as evident from the empirical regularities below, vulnerability to poverty persists because of households’ diminished capacity to mitigate and cope with frequent occurrence of weather extremes. The …

Precipitation Variability And Nitrogen Deposition Alter Root Distribution In A Tallgrass Prairie, Emmalyn P. Terracciano, Michael Schuster, Jeffrey Dukes

The Summer Undergraduate Research Fellowship (SURF) Symposium

Climate change and increases in nitrogen deposition impact ecosystems globally. Projected atmospheric warming allows rain to fall in larger events with longer dry periods in between, increasing rainfall variability in many regions. Concurrently, the combustion of fossil fuels and the heavy use of nitrogen fertilizers continue to increase the availability of nitrogen globally. However, not much is known about how these global change factors, increased rainfall variability and nitrogen deposition, interact with each other to affect ecosystem functions, particularly belowground where root production contributes to soil carbon pools- an important component in regulating climate. In order to study these factors, …

Wetland Sediment Nutrient Flux In Response To Proposed Hydrologic Reconnection And Climate Warming, James T. Smit

Masters Theses

Wetland restoration and creation are common practices, but wetlands restored or created on former agricultural land may act as a source of nutrients, rather than as a sink. I studied P sediment-water exchange in two flooded celery fields (west and east), which are designated for wetland restoration, in order to assess the effects that hydrologic reconnection of the area to an adjacent creek would have on P dynamics. We also examined the influence of climate change, specifically warming temperatures, by conducting the sediment-water exchange experiments at ambient and plus 2°C temperature conditions. Lab-based sediment core incubations revealed that TP release …

Irrigation Demand In A Changing Climate: Using Disaggregate Data To Predict Future Groundwater Use, Calvin R. Shaneyfelt

Department of Agricultural Economics: Dissertations, Theses, and Student Research

The paper estimates an irrigation water demand function using disaggregate climate and well data over a 33 year time period. Aggregating climate information over long periods, like a year, causes a loss of detail on temporal climatic variation, while aggregating climate information over space causes a loss of detail on spatial variation. This analysis uses disaggregate climate variation at a temporospatial level to determine the effects of climate on groundwater use. Results show that increased heat, measured in cooling degree-days, correlates with increased water use, while increased precipitation correlates with decreased water use. However, the effects are generally magnified for …

Energy And Climate Change: A Climate Prediction Market, Michael P. Vandenbergh, Kaitlin T. Raimi, Jonathan M. Gilligan

Vanderbilt Law School Faculty Publications

Much of energy policy is driven by concerns about climate change. Views about the importance of carbon emissions affect debates on topics ranging from the regulation of electricity generation and transmission to the need for incentives to develop emerging technologies. Government efforts to fund and communicate climate science have been extraordinary, but recent polling suggests that roughly half of the American population is unsure or does not believe that anthropogenic climate change is occurring. Among some populations, belief in climate change is declining even as the climate science becomes more certain. Much of the doubt occurs among individuals who support …

Connecting Institutional Discourses And Everyday Understandings Of Climate Change: Viewpoints From A Suburban Neighborhood In Tampa, Florida, Christopher Metzger

USF Tampa Graduate Theses and Dissertations

Despite a general consensus regarding anthropogenic global climate change across the international scientific community, many of the major greenhouse gas producers in the world, especially the United States, are hesitant to implement strict emissions regulations. According to some prominent atmospheric scientists, such as James Hansen and Michael Mann, if industrialized countries continue to produce carbon emissions at current rates, an irreversible planetary tipping point of raising temperatures 2°C above pre-industrial levels could be reached in less than 40 years. Societies have a wealth of information from the natural sciences to understand the climate problem and currently possess the technological means …

Northern Winter Climate Change: Assessment Of Uncertainty In Cmip5 Projections Related To Stratosphere-Troposhere Coupling, E. Manzini, A. Yu. Karpechko, J. Anstey, M. P. Baldwin, R. X. Black, C. Cagnazzo, N. Calvo, A. Charlton-Perez, B. Christiansen, Paolo Davini, E. Gerber, M. Giorgettta, L. Gray, S. C. Hardiman, Y. Y. Lee, D. R. Marsh, Brent A. Mcdaniel, A. Purich, A. A. Scaife, D. Shindell, S. W. Son, S. Watanabe, G. Zappa

Faculty Articles

Future changes in the stratospheric circulation could have an important impact on northern winter tropospheric climate change, given that sea level pressure (SLP) responds not only to tropospheric circulation variations but also to vertically coherent variations in troposphere-stratosphere circulation. Here we assess northern winter stratospheric change and its potential to influence surface climate change in the Coupled Model Intercomparison Project-Phase 5 (CMIP5) multimodel ensemble. In the stratosphere at high latitudes, an easterly change in zonally averaged zonal wind is found for the majority of the CMIP5 models, under the Representative Concentration Pathway 8.5 scenario. Comparable results are also found in …

Circulation, Vol. 19, No. 2, Center For Coastal Physical Oceanography, Old Dominion University

CCPO Circulation

Summer 2014 issue of CCPO Circulation featuring article "Meeting the Challenge of Climate Change" by Dr. Hans Peter Plag, Mitigation & Adaptation Research Insititue (MARI)