Life Sciences Commons^™

Imber- Research For Marine Sustainability: Synthesis And The Way Forward, Eileen Hofmann, Alida Bundy, Ken Drinkwater, Alberto R. Piola, Bernard Avril, Carol Robinson

CCPO Publications

The Integrated Marine Biogeochemistry and Ecosystem Research (IMBER) project aims at developing a comprehensive understanding of and accurate predictive capacity of ocean responses to accelerating global change and the consequent effects on the Earth system and human society. Understanding the changing ecology and biogeochemistry of marine ecosystems and their sensitivity and resilience to multiple drivers, pressures and stressors is critical to developing responses that will help reduce the vulnerability of marine-dependent human communities. This overview of the IMBER project provides a synthesis of project achievements and highlights the value of collaborative, interdisciplinary, integrated research approaches as developed and implemented through …

Climate, Environmental And Socio-Economic Change: Weighing Up The Balance In Vector-Borne Disease Transmission, Paul E. Parham, Joanna Waldock, George K. Christophides, Deborah Hemming, Folashade Agusto, Katherine J. Evans, Nina Fefferman, Holly Gaff, Abba Gumel, Shannon Ladeau

Biological Sciences Faculty Publications

Arguably one of the most important effects of climate change is the potential impact on human health. While this is likely to take many forms, the implications for future transmission of vector-borne diseases (VBDs), given their ongoing contribution to global disease burden, are both extremely important and highly uncertain. In part, this is owing not only to data limitations and methodological challenges when integrating climate-driven VBD models and climate change projections, but also, perhaps most crucially, to the multitude of epidemiological, ecological and socio-economic factors that drive VBD transmission, and this complexity has generated considerable debate over the past 10-15 …

Interactions Among Spruce Beetle Disturbance, Climate Change And Forest Dynamics Captured By A Forest Landscape Model, Christian Temperli, Thomas T. Veblen, Sarah J. Hart, Dominik Kulakowski, Alan J. Tepley

Geography

The risk of bark beetle outbreaks is widely predicted to increase because of a warming climate that accelerates temperature-driven beetle population growth and drought stress that impairs host tree defenses. However, few if any studies have explicitly evaluated climatically enhanced beetle population dynamics in relation to climate-driven changes in forest composition and structure that may alter forest suitability for beetle infestation. We synthesized current understanding of the interactions among climate, spruce beetles (Dendroctonus rufipennis) and forest dynamics to parameterize and further advance the bark beetle module of a dynamic forest landscape model (LandClim) that also integrates fire and wind disturbance …

Rainwater Harvesting And Its Impact On Farming Systems, J. S. Samra

IGC Proceedings (1977-2023)

Landless, small holders and other poors supplement their livelihood and adapt to climate change by grazing, stall feeding with crop residues and fodder cultivated under rainfed and irrigated conditions. Improving productivity by conserving rainfall, ground water recharging, harvesting and recycling of rainwater especially in degraded open access or shared land with community participation was quite successful over a wide range of precipitation and ecological situations. Various types of trenches, bunding, vegetative barriers, gully plugs, ponds, check dams, land slides and mine spoils stabilization etc. retained more soil moisture, seeds, vegetative propagules etc. in situ and prevented soil erosion. It regenerated …

Emission Of Green House Gases From Grasslands And Their Mitigation, Prem N. Sharma, Shyam Khadka

IGC Proceedings (1977-2023)

The concentrations of green house gases (GHG) in the atmosphere began in pre-industrial times and it continues to increase. This could result into an alarming increase in temperature of up to 5.4 ^oC by year 2100 due to a net global annual GHG emission of H 4.5-6.5 Gt C equivalent. About 18% of the world’s GHG are contributed by livestock and related activities on grasslands that are spread over almost 35 million Km².These grasslands give livelihood to over a billion people most of who are poor. Twenty to 70% of the land surface area is degrading often …

Snails From Heavy-Metal Polluted Environments Have Reduced Sensitivity To Carbon Dioxide-Induced Acidity, Hugh Lefcort, David A. Cleary, Aaron M. Marble, Morgan V. Phillips, Timothy J. Stoddard, Lara M. Tuthill, James R. Winslow

Biology Faculty Scholarship

Anthropogenic atmospheric CO2 reacts with water to form carbonic acid (H2CO3) which increases water acidity. While marine acidification has received recent consideration, less attention has been paid to the effects of atmospheric carbon dioxide on freshwater systems—systems that often have low buffering potential. Since many aquatic systems are already impacted by pollutants such as heavy metals, we wondered about the added effect of rising atmospheric CO2 on freshwater organisms. We studied aquatic pulmonate snails (Physella columbiana) from both a heavy-metal polluted watershed and snails from a reference watershed that has not experienced mining pollution. We used gaseous CO2 …

Expanding Eco-Visualization: Sculpting Corn Production, Jennifer E. Figg

Theses and Dissertations

This dissertation expands upon the definition of eco-visualization artwork. EV was originally defined in 2006 by Tiffany Holmes as a way to display the real time consumption statistics of key environmental resources for the goal of promoting ecological literacy. I assert that the final forms of EV artworks are not necessarily dependent on technology, and can differ in terms of media used, in that they can be sculptural, video-based, or static two-dimensional forms that communicate interpreted environmental information. There are two main categories of EV: one that is predominantly screen-based and another that employs a variety of modes of representation …

Identifying Inundation-Driven Effects Among Intertidal Crassostrea Virginica In A Commercially Important Gulf Of Mexico Estuary, Joshua Solomon

Electronic Theses and Dissertations

Sea level rise and changing storm frequency and intensity resulting from climate change create tremendous amounts of uncertainty for coastal species. Intertidal species may be especially affected since they are dependent on daily inundation and exposure. The eastern oyster Crassostrea virginica is an economically and biologically important sessile intertidal species ranging from Canada to the Gulf of Mexico. Declines and changes in distribution of oyster populations has forced commercial harvesting to spread from subtidal to intertidal reefs. We investigated the potential responses of intertidal C. virginica to sea level rise, and the response of larval settlement to sedimentation which is …

Instantaneous Photosynthetic Response To Temperature Of Mature Forest Canopies And Experimentally Warmed Seedlings, Alida C. Mau

Dissertations, Master's Theses and Master's Reports - Open

Tropical trees have been shown to be more susceptible to warming compared to temperate species, and have shown growth and photosynthetic declines at elevated temperatures as little as 3oC above ambient. However, regional and global vegetation models lack the data needed to accurately represent physiological response to increased temperatures in tropical forests. We compared the instantaneous photosynthetic responses to elevated temperatures of four mature tropical rainforest tree species in Puerto Rico and the temperate broadleaf species sugar maple (Acer saccharum) in Michigan. Contrary to expectations, leaves in the upper canopy of both temperate and tropical forests had temperature …

Investigating The Effects Of Short- And Long-Term Climatic Variation On The Water Use Of Three Northern Hardwood Tree Species, Alex R. Collins

Dissertations, Master's Theses and Master's Reports - Open

Many tree species are expected to decline in the northern Midwestern United States due to climate change increasing annual temperature 3-5º C by 2100. Sugar maple (Acer saccharum), an economically important timber and syrup species, is not expected to be sustainable in its current range under projected future climate, while trembling aspen (Populus tremuloides) and red maple (Acer rubrum) are expected to react more favorably to climate change. The success of individual tree species is dependent on how climate change will alter a species environment in regards to water use. Climate change could …

Negative Feedbacks On Bark Beetle Outbreaks: Widespread And Severe Spruce Beetle Infestation Restricts Subsequent Infestation, Sarah J. Hart, Thomas T. Veblen, Nathan Mietkiewicz, Dominik Kulakowski

Geography

Understanding disturbance interactions and their ecological consequences remains a major challenge for research on the response of forests to a changing climate. When, where, and how one disturbance may alter the severity, extent, or occurrence probability of a subsequent disturbance is encapsulated by the concept of linked disturbances. Here, we evaluated 1) how climate and forest habitat variables, including disturbance history, interact to drive 2000s spruce beetle (Dendroctonus rufipennis) infestation of Engelmann spruce (Picea engelmannii) across the Southern Rocky Mountains; and 2) how previous spruce beetle infestation affects subsequent infestation across the Flat Tops Wilderness in northwestern Colorado, which experienced …

Navigating A Pathway Toward Colorado's Water Future: A Review And Recommendations On Colorado's Draft Water Plan, Lawrence J. Macdonnell, Colorado Water Working Group

Books, Reports, and Studies

40 pages (includes color illustrations).

On Underestimation Of Global Vulnerability To Tree Mortality And Forest Die-Off From Hotter Drought In The Anthropocene, Craig D. Allen, David D. Breshears, Nate G. Mcdowell

United States Geological Survey: Staff Publications

Patterns, mechanisms, projections, and consequences of tree mortality and associated broadscale forest die-off due to drought accompanied by warmer temperatures—‘‘hotter drought’’, an emerging characteristic of the Anthropocene—are the focus of rapidly expanding literature. Despite recent observational, experimental, and modeling studies suggesting increased vulnerability of trees to hotter drought and associated pests and pathogens, substantial debate remains among research, management and policy-making communities regarding future tree mortality risks. We summarize key mortalityrelevant findings, differentiating between those implying lesser versus greater levels of vulnerability. Evidence suggesting lesser vulnerability includes forest benefits of elevated [CO2] and increased water-use efficiency; observed and modeled increases …

Effects Of Drought On Forests And Rangelands In The United States: A Comprehensive Science Synthesis, James M. Vose, James S. Clark, Charles H. Luce, Toral Patel-Weynand

United States Department of Agriculture, Forest Service / University of Nebraska-Lincoln: Faculty Publications

This assessment provides input to the reauthorized National Integrated Drought Information System (NIDIS) and the National Climate Assessment (NCA), and it establishes the scientific foundation needed to manage for drought resilience and adaptation. Focal areas include drought characterization; drought impacts on forest processes and disturbances such as insect outbreaks and wildfire; and consequences on forest and rangeland values. Drought can be a severe natural disaster with substantial social and economic consequences. Drought becomes most obvious when large-scale changes are observed; however, even moderate drought can have long-lasting impacts on the structure and function of forests and rangelands without these obvious …

Evolution In Action: Climate Change, Biodiversity Dynamics And Emerging Infectious Disease, Eric P. Hoberg, Daniel R. Brooks

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Climatological variation and ecological perturbation have been pervasive drivers of faunal assembly, structure and diversification for parasites and pathogens through recurrent events of geographical and host colonization at varying spatial and temporal scales of Earth history. Episodic shifts in climate and environmental settings, in conjunction with ecological mechanisms and host switching, are often critical determinants of parasite diversification, a view counter to more than a century of coevolutionary thinking about the nature of complex host–parasite assemblages. Parasites are resource specialists with restricted host ranges, yet shifts onto relatively unrelated hosts are common during phylogenetic diversification of parasite lineages and directly …

Correlation Analysis Of Climatic Variables, Migration And Dengue Cases In Southeast Florida, Brunilda Lugo

Walden Dissertations and Doctoral Studies

Dengue fever is a debilitating, viral, mosquito-borne disease occurring in tropical and subtropical areas in the world. The majority of dengue cases in the United States were acquired in endemic areas by travelers or immigrants. However, in recent years, autochthonous (locally acquired) dengue cases have been diagnosed in Florida. The purpose of this study was to find an association between potential risk factors and the expansion of dengue fever in the United States. Guided by the eco-bio-social framework, which offers a broad assessment of risk factors for the illness, a retrospective design was used with archival data to correlate changes …

Effect Of Temperature On The Phenology Of Chilo Partellus (Swinhoe) (Lepidoptera, Crambidae); Simulation And Visualization Of The Potential Future Distribution Of C. Partellus In Africa Under Warmer Temperatures Through The Development Of Life-Table Parameters, N. Khadioli, Z. E.H. Tonnang, E. Muchugu, G. Ong'amo, T. Achia, I. Kipchirchir, J. Kroschel, B. Le Ru

All Peer-Reviewed Publications

Maize (Zea mays) is a major staple food in Africa. However, maize production is severely reduced by damage caused by feeding lepidopteran pests. In East and Southern Africa, Chilo partellus is one of the most damaging cereal stem borers mainly found in the warmer lowland areas. In this study, it was hypothesized that the future distribution and abundance of C. partellus may be affected greatly by the current global warming. The temperature-dependent population growth potential of C. partellus was studied on artificial diet under laboratory conditions at six constant temperatures (15, 18, 20, 25, 28, 30, 32 and 35 °C), …

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 …

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 …

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 …

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 …

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 …

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 …