Digital Commons Network^™

Characterization Of Enzymatic Properties Of Maize Tps And Tpp Proteins Involved In The Trehalose Pathway, Allison C. Siekman

Department of Environmental Studies: Undergraduate Student Theses

Plant metabolism’s most important skill is its ability to perform photosynthesis, converting light energy of particular wavelengths to stored biochemical energy¹. Like many organisms, plants follow a circadian rhythm. This means that the plant’s energy cycles each day, depending on whether it is day or night. During the day, light energy strikes the plant and is used to make soluble sugars, amino acids, lipids, nucleic acid, and complex carbohydrates. Not all of these compounds are used for immediate growth; a major fraction is saved for storage². During the night, the plant uses 95% of starch, the …

Stormwater Management Education In Nebraska: Integrating Extension, Teaching, And Research, David P. Shelton, Steven Rodie

Discipline-Based Education Research Group Speaker Series

Stormwater management is a critical concern for communities in the United States with populations over 10,000 largely because of mandates to reduce stormwater runoff volumes and associated pollutants. A Stormwater Work Group was organized at the University of Nebraska‐Lincoln (UNL) in 2006 to develop educational programs and materials to address municipal stormwater management through green infrastructure and other best management practices. A USDA‐NIFA grant titled “Improving and Conserving Water Resources through Stormwater Management Education for Community Decision Makers of Today and Tomorrow” was received in 2009 which has further supported and greatly expanded work group efforts. This, coupled with support …

Temperature Changes In Central Asia From 1979 To 2011 Based On Multiple Datasets, Zengyun Hu, Chi Zhang, Q. Steven Hu, Hanqin Tian

Department of Earth and Atmospheric Sciences: Faculty Publications

The arid and semiarid region in central Asia is sensitive and vulnerable to climate variations. However, the sparse and highly unevenly distributed meteorological stations in the region provide limited data for understanding of the region’s climate variations. In this study, the near-surface air temperature change in central Asia from 1979 to 2011 was examined using observations from 81 meteorological stations, three local observation validated reanalysis datasets of relatively high spatial resolutions, and the Climate Research Unit (CRU) dataset. Major results suggested that the three reanalysis datasets match well with most of the local climate records, especially in the low-lying plain …

Stochasticity In Natural Forage Production Affects Use Of Urban Areas By Black Bears: Implications To Management Of Human-Bear Conflicts, Sharon Baruch-Mordo, Kenneth R. Wilson, David L. Lewis, John Broderick, Julie S. Mao, Stewart W. Breck

United States Department of Agriculture Wildlife Services: Staff Publications

The rapid expansion of global urban development is increasing opportunities for wildlife to forage and become dependent on anthropogenic resources. Wildlife using urban areas are often perceived dichotomously as urban or not, with some individuals removed in the belief that dependency on anthropogenic resources is irreversible and can lead to increased human-wildlife conflict. For American black bears (Ursus americanus), little is known about the degree of bear urbanization and its ecological mechanisms to guide the management of human-bear conflicts. Using 6 years of GPS location and activity data from bears in Aspen, Colorado, USA, we evaluated the degree of bear …

Biofrag – A New Database For Analyzing Biodiversity Responses To Forest Fragmentation, Marion Pfeifer, Andrew Tyre

School of Natural Resources: Faculty Publications

Habitat fragmentation studies have produced complex results that are challenging to synthesize. Inconsistencies among studies may result from variation in the choice of landscape metrics and response variables, which is often compounded by a lack of key statistical or methodological information. Collating primary datasets on biodiversity responses to fragmentation in a consistent and flexible database permits simple data retrieval for subsequent analyses. We present a relational database that links such field data to taxonomic nomenclature, spatial and temporal plot attributes, and environmental characteristics. Field assessments include measurements of the response(s) (e.g., presence, abundance, ground cover) of one or more species …

Bringing Resilience To Wildlife Management And Biodiversity Protection, Melinda Harm Benson, Matthew E. Hopton

United States Environmental Protection Agency: Publications

Biological diversity can be considered both temporally (Le., evolutionary time) and/or spatially and reflects the number, variety, and variability of organisms. It includes diversity within species (Le., genetic and morphological), between species (Le., alpha and beta), and among ecosystems (Le., beta and gamma). Over the past few hundred years, human activities have increased species extinction rates by as much as 1,000 times above the background rates that were typical over Earth's history (Figure 2.1) (Millennium Ecosystem Assessment 2005; but see He and Hubbell 2011). In the United States, there are approximately 1,900 species listed as threatened or endangered, with potentially …

Identifying Legal, Ecological And Governance Obstacles, And Opportunities For Adapting To Climate Change, Barbara Cosens, Lance Gunderson, Craig R. Allen, Melinda Harm Benson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Current governance of regional scale water management systems in the United States has not placed them on a path toward sustainability, as conflict and gridlock characterize the social arena and ecosystem services continue to erode. Changing climate may continue this trajectory, but it also provides a catalyst for renewal of ecosystems and a window of opportunity for change in institutions. Resilience provides a bridging concept that predicts that change in ecological and social systems is often dramatic, abrupt, and surprising. Adapting to the uncertainty of climate driven change must be done in a manner perceived as legitimate by the participants …

Introduction [To Automation: The Future Of Weed Control In Cropping Systems]: Scope Of The Problem—Rising Costs And Demand For Environmental Safety For Weed Control, Stephen L. Young, Francis J. Pierce, Pete Nowak

West Central Research and Extension Center, North Platte

Many organic and conventional producers rank weed control as their number one production cost. For organic producers particularly, weed control has become increasingly important as organic production has increased its market share. In conventional systems, herbicide resistance, off-target movement, and increased regulations have left many growers with few alternatives. Added to this is an increasing demand from the public for a safer and more sustainable supply of food. This chapter addresses the problems of mechanized agricultural systems to set the stage for the introduction and adoption of more advanced technology to meet the needs of growers and satisfy the desires …

Root Growth Of Two Perennial Grass Types And Musk Thistle (Carduus Nutans) In Temperate Grasslands Of North America, Chengchou Han, Stephen L. Young

West Central Research and Extension Center, North Platte

Root architecture of prairie grasslands, which depends on plant phenology and edaphic conditions, strongly influences susceptibility to invasion by nonindigenous plant species. Field studies were conducted to compare in situ root growth patterns of warm-season (WS) and cool-season (CS) perennial grasses and musk thistle during a 2-yr period that included a drought in the second year. In 2 yr, CS grasses had the highest amount of roots (1,296 m roots m^–2 [395 ft roots ft^–2]) across shallow (0 to 28 cm [0 to 11 in.]), medium (28 to 56 cm), and deep (56 to 98 cm) depths …

Envr 499a And 499b: Environmental Studies Senior Thesis I & Ii Ace 10 Course, David C. Gosselin, Sara Cooper

Accreditation Quality Initiative

ACE 10 Question

To what extent to can senior thesis posters be used to assess the ACE 10 outcome?

ENVR 499 Course Sequence

Learning Outcomes

Student Work

Posters Featured at Environmental Studies Showcase

Rubric Development

Improving ACE 10 Learning

Eutrophication Weakens Stabilizing Effects Of Diversity In Natural Grasslands, Yann Hautier, Eric W. Seabloom, Elizabeth T. Borer, Peter B. Adler, W. Stanley Harpole, Helmut Hillebrand, Eric M. Lind, Andrew S. Macdougall, Carly J. Stevens, Jonathan D. Bakker, Yvonne M. Buckley, Chengjin Chu, Scott L. Collins, Pedro Daleo, Ellen I. Damschen, Kendi F. Davies, Philip A. Fay, Jennifer Firn, Daniel S. Gruner, Virginia L. Jin, Julia A. Klein, Johannes M. H. Knops, Kimberly J. La Pierre, Wei Li, Rebecca L. Mcculley, Brett A. Melbourne, Joslin L. Moore, Lydia R. O’Halloran, Suzanne M. Prober, Anita C. Risch, Mahesh Sankaran, Martin Schuetz, Andy Hector

School of Biological Sciences: Faculty Publications

Studies of experimental grassland communities^1–7 have demonstrated that plant diversity can stabilize productivity through species asynchrony, in which decreases in the biomass of some species are compensated for by increases in others^1,2. However, it remains unknown whether these findings are relevant to natural ecosystems, especially those for which species diversity is threatened by anthropogenic global change^8–11. Here we analyse diversity–stability relationships from 41 grasslands on five continents and examine how these relationships are affected by chronic fertilization, one of the strongest drivers of species loss globally⁸. Unmanipulated communities with more species had greater …

Metolachlor Metabolite (Mesa) Reveals Agricultural Nitrate-N Fate And Transport In Choptank River Watershed, Gregory Mccarty, Cathleen Hapeman, Clifford Rice, Dean Hively, Laura Mcconnell, Ali Sadeghi, Megan Lang, David Whitall, Krystyna Bialek, Peter Downey

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

Over 50% of streams in the Chesapeake Bay watershed have been rated as poor or very poor based on the index of biological integrity. The Choptank River estuary, a Bay tributary on the eastern shore, is one such waterway, where corn and soybean production in upland areas of the watershed contribute significant loads of nutrients and sediment to streams. We adopted a novel approach utilizing the relationship between the concentration of nitrate-N and the stable, water-soluble herbicide degradation product MESA {2-[2-ethyl-N-(1- methoxypropan-2-yl)-6-methylanilino]-2-oxoethanesulfonic acid} to distinguish between dilution and denitrification effects on the stream concentration of nitrate-N in agricultural subwatersheds. The …

Plant Community Composition And Structure Monitoring For Agate Fossil Beds National Monument, 2013 Annual Report, Isabel W. Ashton, Michael Prowatzke

United States National Park Service: Publications

Introduction

During the last century, much of the prairie within the Northern Great Plains has been plowed for cropland, planted with non-natives to maximize livestock production, or otherwise developed, making it one of the most threatened ecosystems in the United States. Within Nebraska, greater than 77% of the area of native mixed-grass prairie has been lost since European settlement (Samson and Knopf 1994). The National Park Service (NPS) plays an important role in preserving and restoring some of the last pieces of intact prairies within its boundaries. The stewardship goal of the NPS is to “preserve ecological integrity and cultural …

Panarchy: Theory And Application, Craig R. Allen, David G. Angeler, Ahjond S. Garmestani, Lance H. Gunderson, C. S. Holling

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The concept of panarchy provides a framework that characterizes complex systems of people and nature as dynamically organized and structured within and across scales of space and time. It has been more than a decade since the introduction of panarchy. Over this period, its invocation in peer-reviewed literature has been steadily increasing, but its use remains primarily descriptive and abstract. Here, we discuss the use of the concept in the literature to date, highlight where the concept may be useful, and discuss limitations to the broader applicability of panarchy theory for research in the ecological and social sciences. Finally, we …

Introduction: Social-Ecological Resilience And Law, Ahjond S. Garmestani, Craig R. Allen, Craig Anthony Arnold, Lance H. Gunderson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Environmental law is intimately connected to ecological concepts and understanding. The legal instruments, institutions, and administration of law in the United States are predicated on assumptions that nature is globally stable and that the inherent variability in ecological systems is bounded. This current legal framework is based upon an understanding of ecological systems operating near an equilibrium, or if disturbed, moving back toward an equilibrium. Such assumptions make much current environmental law ill-suited for many pressing environmental issues (Ruhl 1999; Garmestani et al. 2009; Craig 2010; Verchick 2010; Benson and Garmestani 2011). Emerging environmental challenges, such as cross-boundary water governance …

Combining Limnology And Palaeolimnology To Investigate Recent Regime Shifts In A Shallow, Eutrophic Lake, Linda Randsalu-Wendrup, Daniel J. Conley, Jacob Carstensen, Lars-Anders Hansson, Christer Brönmark, Sherilyn C. Fritz, Preetam Choudhary, Joyanto Routh, Dan Hammarlund

Department of Earth and Atmospheric Sciences: Faculty Publications

In this study, we demonstrate that an integrated approach, combining palaeolimnological records and limnological monitoring data, can increase our understanding of changing ecological patterns and processes in shallow lakes. We focused on recent regime shifts in shallow Lake Krankesjön, southern Sweden, including the collapse of the clear-water state in 1975 and its subsequent recovery in the late 1980s. We used diatom, hydrocarbon, and biogenic silica sediment records, in concert with limnological data sets on nutrient concentrations, water clarity, chlorophyll-a and water depth, to investigate the shifts. The shift from clear to turbid conditions was abrupt and occurred over 1 to …

Influence Of Egg Oiling On Colony Presence Of Ring-Billed Gulls, Travis L. Devault, Paige M. Schmidt, Fred E. Pogmore, John Gobeille, Jerrold L. Belant, Thomas W. Seamans

United States Department of Agriculture Wildlife Services: Staff Publications

Egg oiling is a form of management in which bird eggs are coated with mineral or corn oil, preventing gas exchange through the shell and killing embryos. Unlike other nestdisturbance techniques, egg oiling reportedly precludes colony abandonment and, thus, can be advantageous when managers wish to limit dispersal within the breeding season to other locations while stabilizing the population or reducing productivity. However, unintended, indirect effects of egg oiling are not well-characterized. We evaluated the influence of egg oiling on ring-billed gulls (Larus delawarensis) within the Lake Champlain basin, Vermont, during the nesting season to determine whether egg …

Geog 140: Human Geography—A Peer Review Of Teaching Project Inquiry Portfolio, Katherine Nashleanas

UNL Faculty Course Portfolios

Large lecture classes, often of 100 students or more, present unique challenges to both teaching and learning. The common method of “delivery” by instructors is lecture, often augmented by a set of Power Point slides while the research literature shows that this more traditional way of teaching does not reach students in the way we hope and often assume. At the same time, most of the current students populating these classes are born of the Digital Age and have different expectations for learning, requiring new approaches in the classroom. Faculty are exhorted to incorporate more critical thinking in their classes …

Humic Substances Interfere With Detection Of Pathogenic Prion Protein, Christen B. Smith, Clarissa J. Booth, Tyler J. Wadzinski, Giuseppe Legname, Rick Chappell, Christopher J. Johnson, Joel A. Pedersen

United States Geological Survey: Staff Publications

Studies examining the persistence of prions (the etiological agent of transmissible spongiform encephalopathies) in soil require accurate quantification of pathogenic prion protein (PrP^TSE) extracted from or in the presence of soil particles. Here, we demonstrate that natural organic matter (NOM) in soil impacts PrP^TSE detection by immunoblotting. Methods commonly used to extract PrP^TSE from soils release substantial amounts of NOM, and NOM inhibited PrP^TSE immunoblot signal. The degree of immunoblot interference increased with increasing NOM concentration and decreasing NOM polarity. Humic substances affected immunoblot detection of prion protein from both deer and hamsters. We also …

Humic Substances Interfere With Detection Of Pathogenic Prion Protein, Christen B. Smith, Clarissa J. Booth, Tyler J. Wadzinski, Giuseppe Legname, Rick Chappell, Christopher J. Johnson, Joel A. Pedersen

United States Geological Survey: Staff Publications

Studies examining the persistence of prions (the etiological agent of transmissible spongiform encephalopathies) in soil require accurate quantification of pathogenic prion protein (PrPTSE) extracted from or in the presence of soil particles. Here, we demonstrate that natural organic matter (NOM) in soil impacts PrPTSE detection by immunoblotting. Methods commonly used to extract PrPTSE from soils release substantial amounts of NOM, and NOM inhibited PrPTSE immunoblot signal. The degree of immunoblot interference increased with increasing NOM concentration and decreasing NOM polarity. Humic substances affected immunoblot detection of prion protein from both deer and hamsters. We also establish that after interaction with …

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 …

Anthropogenics: Human Influence On Global And Genetic Homogenization Of Parasite Populations, Dante S. Zarlenga, Eric P. Hoberg, Benjamin Rosenthal, Simonetti Mattiucci, Giuseppe Nascetti

Harold W. Manter Laboratory of Parasitology: Faculty Publications

The distribution, abundance, and diversity of life on Earth have been greatly shaped by human activities. This includes the geographic expansion of parasites; however, measuring the extent to which humans have influenced the dissemination and population structure of parasites has been challenging. In-depth comparisons among parasite populations extending to landscape-level processes affecting disease emergence have remained elusive. New research methods have enhanced our capacity to discern human impact, where the tools of population genetics and molecular epidemiology have begun to shed light on our historical and ongoing influence. Only since the 1990s have parasitologists coupled morphological diagnosis, long considered the …

Modeling Black Bear Population Dynamics In A Human-Dominated Stochastic Environment, David L. Lewis, Stewart W. Breck, Kenneth R. Wilson, Colleen T. Webb

United States Department of Agriculture Wildlife Services: Staff Publications

Many large carnivore populations exist in human-influenced stochastic environments where availability of natural food sources vary annually and anthropogenic food sources can supplement energetic demands, but at a potential demographic cost due to human–wildlife conflict and subsequent conflict management. Understanding how these competing factors influence a population is complex and difficult to study, but here we demonstrate the utility of using a stochastic projection matrix model and perturbation analysis to gain insight into this problem. We modeled a black bear population subjected to stochastic failures of fruiting and masting species, but with access to garbage in urban environments.We parameratized our …

Environmental Analysis Of Goes-R Proving Ground Convection Initiation Forecasting Algorithms, Jason M. Apke

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

The enhanced temporal and spatial resolution of the GOES-R series will allow for the use of cloud top cooling based convection initiation (CI) forecasting algorithms. Two such algorithms have been created on the current generation of GOES satellites: theUniversityofWisconsincloud top cooling algorithm (UWCTC) and the University of Alabama-Huntsville’s satellite convection analysis and tracking algorithm (SATCAST). Preliminary analysis of algorithm products has led to speculation over pre-convective environmental effects on algorithm performance, which this study aims to examine. CI indications are used with objective segmentation tools to identify and cluster radar objects over theGreat Plainsbased on reflectivity quantitative and spatial thresholds. …

Department Of Biological Systems Engineering Newsletter, October 2013

BSE Department Magazine

No abstract provided.

American Society Of Parasitologists Newsletter, V. 35, No. 2, Fall 2013, Scott Lyell Gardner

American Society of Parasitologists: Newsletter

An issue of the American Society of Parasitologists Newsletter, also known as the Newsletter of the Journal of Parasitology.

Green Revolving Funds Provide Community Benefits Through Innovation, Amanda Johnson

Op-Eds from ENSC230 Energy and the Environment: Economics and Policies

Green Revolving Funds Provide Community Benefits Through Innovation

Plant Community Composition And Structure Monitoring In Scotts Bluff National Monument, 2013 Annual Report, Isabel Ashton, Michael Prowatzke

United States National Park Service: Publications

Introduction

During the last century, much of the prairie within the Northern Great Plains has been plowed for cropland, planted with non-natives to maximize livestock production, or otherwise developed, making it one of the most threatened ecosystems in the United States. Within Nebraska, greater than 77% of the area of native mixed grass prairie has been lost since European settlement (Samson and Knopf 1994). The National Park Service (NPS) plays an important role in preserving and restoring some of the last pieces of intact prairies within its boundaries. The stewardship goal of the NPS is to “preserve ecological integrity and …

Integration Of Sustainability In Higher Education: Three Case Studies Of Curricular Implementation, David Gosselin, Rod Parnell, Nicholas J. Smith-Sebasto, Shirley Vincent

School of Natural Resources: Faculty Publications

The integration of sustainability into higher education academic programs is occurring at an accelerated pace in response to international and national imperatives to rethink the way it serves the needs of society. Three case studies from the University of Nebraska- Lincoln, Northern Arizona University, and Kean University (NJ) outlines the academic structure, program, resources, the motivation and mechanisms for curricular change, key sustainability-learning outcomes and program goals, curricular changes, and assessment strategies these institutions used to integrate sustainability into their undergraduate curriculum. These three case studies exhibit several commonalities. They emphasize systems thinking and explicitly link human behavior and ecological …

Inconsistent Outcomes Of Heterogeneity-Based Management Underscore Importance Of Matching Evaluation To Conservation Objectives, Devan Allen Mcgranahan, David M. Engle, Samuel D. Fuhlendorf, Stephen L. Winter, James R. Miller, Diane M. Debinski

School of Natural Resources: Faculty Publications

Conservation policy often incentivizes managers of human-impacted areas to create landscape heterogeneity to maximize biodiversity. In rangeland, patchy disturbance regimes create landscape heterogeneity (patch contrast), but outcomes of heterogeneity-based management are rarely tested for a universal response. We analyzed four habitat variables—vegetation structure, plant functional group composition, litter cover, and bare ground—from five experimental rangelands in Oklahoma and Iowa, USA. We tested for response consistency to heterogeneity-based management across and within locations. We calculated effect sizes for each variable to compare patch contrast on pastures managed for heterogeneity (patch burn-grazing) and pastures managed for homogeneity (grazing with homogeneous fire regimes). …