Life Sciences Commons^™

Nitrogen Fertilization Has A Stronger Effect On Soil Nitrogen-Fixing Bacterial Communities Than Elevated Atmospheric Co2, Sean T. Berthrong, Chris M. Yeager, Laverne Gallegos-Graves, Blaire Steven, Stephanie A. Eichorst, Robert B. Jackson, Cheryl R. Kuske

Scholarship and Professional Work - LAS

Biological nitrogen fixation is the primary supply of N to most ecosystems, yet there is considerable uncertainty about how N-fixing bacteria will respond to global change factors such as increasing atmospheric CO₂ and N deposition. Using the nifH gene as a molecular marker, we studied how the community structure of N-fixing soil bacteria from temperate pine, aspen, and sweet gum stands and a brackish tidal marsh responded to multiyear elevated CO₂ conditions. We also examined how N availability, specifically, N fertilization, interacted with elevated CO₂ to affect these communities in the temperate pine forest. Based on data …

Approaches To Restoration: Assessing The Roles Of Structure And Function In Saltmarsh Restoration In Light Of Climate Change, Abby O. Pearson Ms

All Student Scholarship

The aim of this thesis is to review the current goals and methods for salt marsh restoration, to question how those goals and methods may change in light of global change, and to present a case study that offers a look at the kinds of information that can be gleaned by studying both structure and functionality in restoration.

Defining The Physiochemical, Biological And Habitat Requirements For The Upper Extant Of Oncorhynchus Mykiss Distribution, Emily Powers

Journal of Earth and Life Science

The distribution of rainbow trout is strongly influenced by their habitat. As climatic conditions change, the distribution of rainbow trout populations will change along with them. The objective of this study was to identify the particular habitat parameters that rainbow trout select for in this lotic system and to specifically assess how this relates to the upper extant of their distribution. By assessing the distribution of the upper extant specifically, future research may be conducted to better assess climatic changes on a small and/or large scale basis. A 9,000 m section of the Clearwater River was used as the study …

Linking Rainforest Ecophysiology And Microclimate Through Fusion Of Airborne Lidar And Hyperspectral Imagery, Eben N. Broadbent, Angélica M. Zambrano, Gregory P. Asner, Christopher B. Field, Brad E. Rosenheim, Ty Kennedy-Bowdoin, David E. Knapp, David Burke, Christian Giardina, Susan Cordell

Marine Science Faculty Publications

We develop and validate a high-resolution three-dimensional model of light and air temperature for a tropical forest interior in Hawaii along an elevation gradient varying greatly in structure but maintaining a consistent species composition. Our microclimate models integrate high-resolution airborne waveform light detection and ranging data (LiDAR) and hyperspectral imagery with detailed microclimate measurements. We then use modeled microclimate and forest structural and compositional variables to explain variation in spatially explicit measurements of leaf traits, including gas exchange and structure. Our results highlight the importance of: (1) species differences in leaf traits, with species explaining up to 65% of the …

The Influences Of Poultry Litter Biochar And Water Source On Radish Growth And Nutrition, Julia Allen, David E. Longer, Edward E. Gbur, Lichen Hao

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Many row-crop fields today have declined in soil fertility due to poor management practices and overuse of pesticides. Under these conditions, plant nutrient uptake can be sub-optimal. There are several soil amendments that can be used to improve soil quality and plant growth. This study focused on the addition of biochar to the soil and the use of structured water to enhance plant growth. Biochar is produced by pyrolysis of organic feedstocks. Previous studies which focused on biochar have shown an increase in plant yield, nutrient availability in the soil, and soil water holding capacity. Structured water is the liquid …

Krill, Climate, And Contrasting Future Scenarios For Arctic And Antarctic Fisheries, Margaret M. Mcbride, Padmini Dalpadado, Kenneth F. Drinkwater, Olav Rune Godø, Alistair J. Hobday, Anne B. Hollowed, Trond Kristiansen, Eugene J. Murphy, Patrick H. Ressler, Sam Subbey, Eileen E. Hofmann, Harald Loeng

CCPO Publications

Arctic and Antarcticmarine systems have incommon high latitudes, large seasonal changes in light levels, cold air and sea temperatures, and sea ice. In other ways, however, they are strikingly different, including their: age, extent, geological structure, ice stability, and foodweb structure. Both regions contain very rapidly warming areas and climate impacts have been reported, as have dramatic future projections. However, the combined effects of a changing climate on oceanographic processes and foodweb dynamics are likely to influence their future fisheries in very different ways. Differences in the life-history strategies of the key zooplankton species (Antarctic krill in the Southern Ocean …

Grassland Sustainability In Kentucky: Case Studies Quantifying The Effects Of Climate Change On Slug Herbivory In Pastures And Different Home Lawn Systems On Turf Greenhouse Gas Emissions, Daniel Adam Weber

Theses and Dissertations--Plant and Soil Sciences

Grasslands comprise the greatest biome by land area, are sensitive to environmental factors affected by climate change, and can impact future climate change through their ability to store and release greenhouse gasses (GHGs). I performed two studies: 1) evaluated the effects of increased temperature and precipitation on slug herbivory/abundance and pasture forage production; 2) quantified different homeowner lawn system effects on soil-to-atmosphere GHG emissions. Climate change will likely affect pasture forage production, with implications for slug herbivory and abundance. I found little evidence that slugs have or will have significant effects on pasture production or plant community. Warming altered the …

Egg Cannibalism In A Gull Colony Increases With Sea Surface Temperature, Lynelle M. Weldon, Shandelle M. Henson, James Hayward, Brianna G. Payne, Libby C. Megna, Andre E. Moncrieff

Faculty Publications

Cannibalism occurs regularly across a broad range of taxa with a variety of ecological and evolutionary consequences. Rises in sea surface temperature (SST) have been linked to increased cannibalism in some species, including polar bears (Ursus maritimus), Peruvian anchovy (Engraulis ringens), and Peruvian hake (Merluccius gayi peruanus), and might be expected in birds that depend on marine food webs for sustenance. Increased SSTs are associated with lowered ocean thermoclines and weakened upwellings. These changes, in turn, lead to decreased productivity in surface water and movement of surviving forage fish to deeper water, thereby food-stressing surface feeders such as gulls, diminishing …

Ecotypes Of An Ecologically Dominant Prairie Grass (Andropogon Gerardii) Exhibit Genetic Divergence Across The U.S. Midwest Grasslands’ Environmental Gradient, Miranda M. Grey, Paul St. Amand, Nora M. Bello, Matthew B. Galliart, Mary Knapp, Karen A. Garrett, Theodore J. Morgan, Sarah G. Baer, Brian R. Maricle, Eduard D. Akhunov, Loretta C. Johnson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Big bluestem (Andropogon gerardii) is an ecologically dominant grass with wide distribution across the environmental gradient of U.S. Midwest grasslands. This system offers an ideal natural laboratory to study population divergence and adaptation in spatially varying climates.

Objectives were to: (i) characterize neutral genetic diversity and structure within and among three regional ecotypes derived from 11 prairies across the U.S. Midwest environmental gradient, (ii) distinguish between the relative roles of isolation by distance (IBD) vs. isolation by environment (IBE) on ecotype divergence, (iii) identify outlier loci under selection and (iv) assess the association between outlier loci and climate.

Using two …

Wetlands And Greenhouse Gas Fluxes: Causes And Effects Of Climate Change – A Meta-Analysis, Robert E. Ventura

Pomona Senior Theses

Climate change is one of the largest problems facing this generation. Anthropogenically caused increases of greenhouse gas emissions is a significant culprit to this problem. Although the obvious problems such as cars, industry, and urbanism garnish a significant amount of the criticism, natural sources such as wetlands are also beginning to contribute to this issue. This is becoming increasingly significant as wetlands shift from being sinks of greenhouse gases to becoming sources as various anthropogenic impacts, including global warming itself, begin to affect the health of the wetlands. The aim of this project is to look at four common types …

Lineage-Specific Transcriptional Profiles Of Symbiodinium Spp. Unaltered By Heat Stress In A Coral Host, Daniel J. Barshis, Jason T. Ladner, Thomas A. Oliver, Stephen R. Palumbi

Biological Sciences Faculty Publications

Dinoflagellates of the genus Symbiodinium form an endosymbiosis with reef building corals, in which photosynthetically derived nutrients comprise the majority of the coral energy budget. An extraordinary amount of functional and genetic diversity is contained within the coral-associated Symbiodinium, with some phylotypes (i.e., genotypic groupings), conferring enhanced stress tolerance to host corals. Recent advances in DNA sequencing technologies have enabled transcriptome-wide profiling of the stress response of the cnidarian coral host; however, a comprehensive understanding of the molecular response to stress of coral-associated Symbiodinium, as well as differences among physiologically susceptible and tolerant types, remains largely unexplored. Here, …

Can We Predict The Future: Juvenile Finfish And Their Seagrass Nurseries In The Chesapeake Bay, Cynthia M. Jones

OES Faculty Publications

The importance of estuarine seagrass beds as nurseries for juvenile fish has become a universal paradigm, especially for estuaries that are as important as the Chesapeake Bay. Yet, scientific tests of this hypothesis were equivocal depending on species, location, and metrics. Moreover, seagrasses themselves are under threat and one-third of seagrasses have disappeared worldwide with 65 of their losses occurring in estuaries. Although there have been extensive studies of seagrasses in the Chesapeake Bay, surprisingly few studies have quantified the relationship between seagrass as nurseries for finfish in the Bay. Of the few studies that have directly evaluated the use …

The Extent Of Heat On Health And Sustainable Farming In Ghana - Bawku East, Kwasi Frimpong, Jacques Oosthuizen, Eddie J. Van Etten

Research outputs 2014 to 2021

Little is known about the health effects of heat in outdoor work and appropriate work and rest schedules for farmers working in developing countries. As temperatures continue to increase in tropical regions, such as Northern Ghana, it is necessary to evaluate how farmers experience and respond to high heat exposures. In this study, WBGT (Wet Bulb Globe Temperature) estimates and the ISO work / rest standards were applied to a cohort of farmers in the rural areas of Bawku East, Northern Ghana, to assess how farmers respond to high heat and how much they rest to protect their health, as …

Changing Forest Water Yields In Response To Climate Warming: Results From Long-Term Experimental Watershed Sites Across North America, Irena F. Creed, Adam T. Spargo, Julia A. Jones, Jim M. Buttle, Mary B. Adams, Fred D. Beall, Eric G. Booth, John L. Campbell, Dave Clow, Kelly Elder, Mark B. Green, Nancy B. Grimm, Chelcy Miniat, Patricia Ramlal, Amartya Saha, Stephen Sebestyen, Dave Spittlehouse, Shannon Sterling, Mark W. Williams, Rita Wrinkler, Huaxia Yao

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

Climate warming is projected to affect forest water yields but the effects are expected to vary. We investigated how forest type and age affect water yield resilience to climate warming. To answer this question, we examined the variability in historical water yields at long-term experimental catchments across Canada and the United States over 5-year cool and warm periods. Using the theoretical framework of the Budyko curve, we calculated the effects of climate warming on the annual partitioning of precipitation (P) into evapotranspiration (ET) and water yield. Deviation (d) was defined as a catchment’s change in actual ET divided by P …

Finding Them Before They Find Us: Informatics, Parasites, And Environments In Accelerating Climate Change, Daniel R. Brooks, Eric P. Hoberg, Walter A. Boeger, Scott Lyell Gardner, Kurt E. Galbreath, David Herczeg, Hugo H. Mejía-Madrid, S. Elizabeth Rácz, Altangerel Tsogtsaikhan Dursahinhan

Harold W. Manter Laboratory of Parasitology: Faculty Publications

Parasites are agents of disease in humans, livestock, crops, and wildlife and are powerful representations of the ecological and historical context of the diseases they cause. Recognizing a nexus of professional opportunities and global public need, we gathered at the Cedar Point Biological Station of the University of Nebraska in September 2012 to formulate a cooperative and broad platform for providing essential information about the evolution, ecology, and epidemiology of parasites across host groups, parasite groups, geographical regions, and ecosystem types. A general protocol, documentation–assessment–monitoring–action (DAMA), suggests an integrated proposal to build a proactive capacity to understand, anticipate, and respond …

Drought-Induced Woody Plant Mortality In An Encroached Semi-Arid Savanna Depends On Topoedaphic Factors And Land Management, Dirac L. Twidwell Jr, Carissa L. Wonkka, Charles A. Taylor, Chris B. Zou, Jeremiah J. Twidwell, William E. Rogers

Department of Agronomy and Horticulture: Faculty Publications

Questions: How do recent patterns of drought-induced woody plant mortality in Texas semi-arid savanna compare to the extended drought of the 1950s? Does the relative composition of the woody plant community shift ubiquitously across the landscape following woody plant mortality and dieback or are shifts dependent on differences among species, soils, land use and plant demography?

Location: Texas Agrilife Research Station, Sonora, Texas, USA (30.1° N 100.3° W).

Methods: Following an exceptional drought from 1951 to 1957, a study was conducted to quantify rates of mortality for various woody plant species. In 2011, we repeated this study within three long-term …

Comparison Of Phenology And Pathogen Prevalence, Including Infection With The Ehrlichia Muris-Like (Eml) Agent, Of Ixodes Scapularis Removed From Soldiers In The Midwestern And Northeastern United States Over A 15 Year Period (1997-2012), Ellen Stromdahl, Sarah Hamer, Sarah Jenkins, Lynne Sloan, Phillip Williamson, Erik Foster, Robyn Nadolny, Chad Elkins, Mary Vince, Bobbi Pritt

Biological Sciences Faculty Publications

Background: Since 1997, human-biting ticks submitted to the Department of Defense Human Tick Test Kit Program (HTTKP) of the US Army Public Health Command have been tested for pathogens by PCR. We noted differences in the phenology and infection prevalence among Ixodes scapularis ticks submitted from military installations in different geographic regions. The aim of this study was to characterize these observed differences, comparing the phenology and pathogen infection rates of I. scapularis submitted from soldiers at two sites in the upper Midwest ( Camp Ripley, MN, and Ft. McCoy, WI) and one site in the northeastern US (Ft. Indiantown …

Predicted Wildlife Disease-Related Climate Change Impacts Of Specific Concern To Usda Aphis Wildlife Services, Timothy P. Algeo, Richard B. Chipman, Dennis Slate, Jerome E. Freier, Thomas J. Deliberto

United States Department of Agriculture Wildlife Services: Staff Publications

USDA APHISWildlife Services plans for and responds to a variety of exigencies such as wildlife hazards to aircraft, disease emergence from wildlife translocations, oral rabies vaccine barrier compromises, and extreme weather events. These are often collaborative efforts with state and federal agencies and others. Climate change based in part on fossil fuel use and methane gas emissions has predictable as well as unknown consequences. As a federal leader in wildlife disease research and management, it is incumbent upon Wildlife Services to be current with the scientific literature; assess potential impacts and wildlife disease management intervention needs from predicted climate change …

Musical Chairs In A Boreal Peatland: How Permafrost Thaw Reverses Successional Processes, Mélissa M. Fafard

Theses and Dissertations (Comprehensive)

The current climate trends indicate amplified high latitude warming. Boreal peatlands can be found within those high latitudes and have important functions hydrologically, ecologically and also in terms of carbon cycling. Peatland’s are wetlands that have accumulated more than 40 cm of peat and can range from minerotrophic fens to ombrotrophic bogs. Naturally, a rich fen can be converted to a bog once groundwater sources are cut off by Sphagnum spp. In areas underlain by discontinuous permafrost, landscape changes are occurring particularly rapidly as the permafrost there is sensitive to both vertical and horizontal thaw. The purpose of this thesis …

Carbon Farming In Relation To Western Australian Agriculture, Robert Sudmeyer, Jackson Parker, Tanmoy Nath, Ananda Ghose

Bulletins 4000 -

Carbon farming activities need to return multiple economic and environmental co-benefits to be attractive to land managers. This bulletin summarises concepts underlying carbon farming, how Australia accounts for greenhouse gas emissions and the potential for Western Australian land managers to participate in, and benefit from, carbon farming.

Experiences Of Heat Stress Vulnerability And Climate Change Among Farmers In Ghana, Kwasi Frimpong, Jacques D. Oosthuizen, Eddie J. Van Etten

Research outputs 2014 to 2021

The trend over the last decade of increasing temperature associated with climate change with the impacts being felt in the poorest communities of the developing world is unequivocal. Bawku East of northern Ghana is assessed as one of the poorest communities. Being a farming community the study investigates the extent of farmers’ experiences on heat and climate change. A selected number of 308 farmers from a farming population of over 15,000 were interviewed about heat stress and climate change to gauge their level of vulnerability to heat stress at the household and farm levels, as well as their general experiences …

Fishing Vs. Climate Change: An Example Of Filefish (Thamnaconus Modestus) In The Northern East China Sea, Sukgeun Jung, Hyung Kee Cha

Journal of Marine Science and Technology–Taiwan

The main cause of annual fluctuations in catch and species composition of fisheries is usually uncertain, but a prevailing view has been that fishing effects are more critical than environmental variability. Filefish is a good anecdote: many Korean fisheries scientists have attributed the sudden collapse of Korean filefish fisheries in the early 1990s to overfishing, especially by trawl fisheries in the northern East China Sea (NECS). However, interdisciplinary researches have revealed that climate-driven, multi-decadal variability in oceanic conditions impacts both fish and fisheries around the world. To test the two alternative hypotheses (i.e., fishing and climate) as the major cause …

Seasonal Abundance Of Epiphytic Dinoflagellates Around Coastal Waters Of Jeju Island, Korea, Md. Mahfuzur Rahman Shah, So-Jeong An, Joon-Baek Lee

Journal of Marine Science and Technology–Taiwan

The seasonal abundance of epiphytic dinoflagellates in the intertidal zone of Jeju Island, Korea was quantitatively estimated by monthly collection of macroalgal samples (Rhodophyta, Phaeophyta, and Chlorophyta) from six sampling locations from July 2012 to June 2013. Ten epiphytic dinoflagellate taxa, including eight potentially toxic species Amphidinium carterae, A. operculatum, Gambierdiscus sp., Ostreopsis ovata, Prorocentrum concavum, P. emarginatum, P. lima, and P. rhathymum, were identified. Two Amphidinium and three Prorocentrum species are newly recorded in Korean coastal waters. A significant change in seasonal abundance was recorded with maximum (751.82 ± 223.12 cells g-1 wet weight of algae; cells g-1 hereafter) …

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 Valley, …

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)) …

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 an interval of …

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

Dartmouth Scholarship

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 outside of …

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 or the …

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 century climate …

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 …