Digital Commons Network^™

Life And Landscapes In The Post-Office Communities Of Holt County, Nebraska, Rebecca A. Buller

Great Plains Quarterly (through 2013)

Thumb through the pages of a DeLorme gazetteer of any Great Plains state .and you will find small black diamonds, each with its own place-name, scattered throughout the large-scale maps. For those who are familiar with the area, the existence of some of the diamonds, supposedly marking the location of a community, can be confusing since these markers do not represent contemporary towns. Additionally, when you travel country roads in rural areas of the Great Plains you will stumble upon markers that identify a nearby post office, which, also no longer exists. What do these diamonds on the map represent? …

Constraining The Amplitude Of Late Oligocene Bathymetric Changes In Western Ross Sea During Orbitally-Induced Oscillations In The East Antarctic Ice Sheet: (1) Implications For Glacimarine Sequence Stratigraphic Models, Gavin B. Dunbar, T. R. Naish, Peter J. Barrett, Christopher R. Fielding, R. D. Powell

Department of Earth and Atmospheric Sciences: Faculty Publications

Abstract Late Oligocene shallow glacimarine sequences recovered from western Ross Sea, Antarctica by the Cape Roberts (drilling) Project display orbitally-influenced cycles of advance and retreat of a laterally-extensive ice sheet across the continental shelf, in concert with changes in contemporary water-depth. During interglacial periods, when the glacier terminated on land, the coastline was largely ice-free and wave-influenced, and sediments accumulated in hydrodynamic equilibrium with the contemporary wave-climate. Here, we present estimates of paleobathymetry from intervals of three Milankovitch-duration glacimarine sequences (9, 10 and 11) that accumulated in open ocean conditions. We utilize an approach where the percentage of mud ( …

A Pilot Study Into The Effects Of X-Ray And Computed Tomography Exposure On The Amplification Of Dna From Bone, Britta M. Grieshaber, Daniel L. Osborne, Alison F. Doubleday, Frederika A. Kaestle

Department of Anthropology: Faculty Publications

This research investigates the intersection of radiography and aDNA, two commonly used methods in bioarchaeology. The goal of this project was to investigate the effects of radiation on the ability to amplify DNA from bone. Bones (n = 124) from domestic pig (Sus scrofa) feet were randomly sorted into a control group and four treatment groups: (1) single exposure X-ray; (2) single exposure CT; (3) multiple exposures X-ray; and (4) multiple exposures CT. Number of PCR cycles required to amplify DNA in 100 bp, 200 bp and 400 bp segments were used as a proxy for the …

Intercomparison And Sensitivity Analysis Of Leaf Area Index Retrievals From Lai-2000, Accupar, And Digital Hemispherical Photography Over Croplands, S. Garrigues, N. V. Shabanov, K. Swanson, J. T. Morisette, F Baret, R. B. Myneni

United States National Aeronautics and Space Administration: Publications

Validation of Leaf Area Index (LAI) derived from moderate resolution remote sensing observations generally involves optical technique to measure ground LAI. As the current validation datasets are derived using multiple optical retrieval techniques, assessment of the consistency between these techniques is required. In this study the effective Plant Area Index (PAI_eff) retrievals by three major optical instruments, LAI-2000, AccuPAR, and Digital Hemispherical Photographs (DHPs), were analyzed over 10 crops (soybean, corn, alfalfa, sorghum, peanut and pasture) at Manfredi site in Cordoba province, Argentina. The focus of research was on quantifying PAI_eff sensitivity to the type of instrument, …

Geochemistry In The Modern Soil Survey Program, M. A. Wilson, R. Burt, J. M. Scheyer, A. B. Jenkins, J. V. Chiaretti, M. G. Ulmer

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

Elemental analysis has played an important role in the characterization of soils since inception of the soil survey in the US. Recent efforts in analysis of trace and major elements (geochemistry) have provided necessary data to soil survey users in a variety of areas. The first part of this paper provides a brief overview of elemental sources, forms, mobility, and bioavailability; critical aspects important to users of soil survey geochemical data for appropriate use and interpretations. Examples are provided based on data gathered as part of the US soil survey program. The second part addresses the organization of sample collection …

Graduate Connections- February 2008

Graduate Connections: A Newsletter for UNL Graduate Students

In This Issue:

Click on links to navigate the newsletter

Navigating Graduate School........... 1

The Dissertation Presentation

Good Practices in Graduate

Education........................................ 4

Helping Students Avoid Plagiarism

Code of Conduct for Teaching

Teaching Tip ...................................... 5

Identifying Relative Importance

Essential Connections...................... 6

Graduate Studies Web Site

Graduate Bulletin Online

Professional Development............... 6

Responding to Academic Job Offers

PFF Call for Nominations

Taking Charge of Your Professional Development

Solving a Teaching Problem

Interactions........................................10

Grad Award Winners

Grad Student Association News

Funding Opportunities.....................12

Resources for Researchers..............14

NEAR Center

Grant Writing Seminar

Announcements................................14

Grad Student …

Effects Of Climate Change On Energy Production And Use In The United States, Thomas Wilbanks, Vatsal Bhatt, Daniel Bilello, Stanley Bull, James Ekmann, William Horak, Y. Joe Huang, Mark D. Levine, Michael J. Sale, David Schmalzer, Michael J. Scott

United States Department of Energy: Publications

Climate change is expected to have noticeable effects in the United States: a rise in average temperatures in most regions, changes in precipitation amounts and seasonal patterns in many regions, changes in the intensity and pattern of extreme weather events, and sea level rise. Some of these effects have clear implications for energy production and use. For instance, average warming can be expected to increase energy requirements for cooling and reduce energy requirements for warming. Changes in precipitation could affect prospects for hydropower, positively or negatively. Increases in storm intensity could threaten further disruptions of the sorts experienced in 2005 …

Food Security Under Climate Change, Molly E. Brown, Chris C. Funk

United States National Aeronautics and Space Administration: Publications

Some of the most profound and direct impacts of climate change over the next few decades will be on agricultural and food systems. On page 607 of this issue, Lobell et al. (1) show that increasing temperatures and declining precipitation over semiarid regions are likely to reduce yields for corn, wheat, rice, and other primary crops in the next two decades. These changes could have a substantial impact on global food security.

Since the 1990s, rising commodity prices and declining per capita cultivated area have led to decreases in food production, eroding food security in many communities …

Water Current ,Volume 40, No. 1, Winter 2008

Water Current Newsletter

Water Quality Subject of Fifth Water Law, Policy and Science Conference By Steve Ress
Water Center History nears Completion By Steve Ress
A Wake-up Call on Climate Change
Meet the Faculty
Planning Begins for June Tour of Republican River Basin By Steve Ress
LB 701: Is it an Answer to Nebraska’s Republican River Problems? By Katherine Kalisek-Vogel
Griffin Named Groundwater Foundation President
Jackson Joins Water Center as Intern
Spring Seminars Continue Through April 16
Nebraska DNR Sponsors Modeling Group Meetings By Steve Ress
Nebraska’s Current Top 10 Water Challenges
ENWRA: Accessing Groundwater Resources in Eastern Nebraska By Julie Wragge
Ethanol …

University Students’ Conceptualization And Interpretation Of Topographic Maps, Douglas Clark, Stephen Reynolds, Vivian Lemanowski, Thomas Stiles, Senay Yaşar-Purzer, Sian Proctor, Elizabeth B. Lewis, Charlotte Stromfors, James Corkins

Department of Teaching, Learning, and Teacher Education: Faculty Publications

This study investigates the strategies and assumptions that college students entering an introductory physical geology laboratory use to interpret topographic maps, and follows the progress of the students during the laboratory to analyze changes in those strategies and assumptions. To elicit students’ strategies and assumptions, we created and refined a topographic visualization test that was administered before and after instruction to 26 students during the first semester of the study and to 92 students during the second semester. To more deeply understand how students think about and conceptualize topographic maps, we focused on eight individual students who were interviewed about …

The Dynastinae (Coleoptera: Scarabaeidae) Of The Bahamas With A Description Of A New Species Of Cyclocephala From Great Inagua Island, Brett C. Ratcliffe, Ronald D. Cave

University of Nebraska State Museum: Entomology Papers

The seven genera and 13 species of dynastine scarabs recorded from the Bahamas are reviewed. Two of those species are endemic, including Cyclocephala dolichotarsa Ratcliffe and Cave, new species, described from Great Inagua Island. Eleven species are also known to occur in the USA and/or Cuba. Six species are probably not established based on infrequency of collection.

A Test Of The Cross-Scale Resilience Model: Functional Richness In Mediterranean-Climate Ecosystems, Donald A. Wardwell, Craig R. Allen, Garry D. Peterson, Andrew J. Tyre

School of Natural Resources: Faculty Publications

Ecological resilience has been proposed to be generated, in part, in the discontinuous structure of complex systems. Environmental discontinuities are reflected in discontinuous, aggregated animal body mass distributions. Diversity of functional groups within body mass aggregations (scales) and redundancy of functional groups across body mass aggregations (scales) has been proposed to increase resilience. We evaluate that proposition by analyzing mammalian and avian communities of Mediterranean-climate ecosystems. We first determined that body mass distributions for each animal community were discontinuous. We then calculated the variance in richness of function across aggregations in each community, and compared observed values with distributions created …

Equilibrium Sampling Used To Monitor Malodors In A Swine Waste Lagoon, Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.

Buffered, Lagged, Or Cooled? Disentangling Hyporheic Influences On Temperature Cycles In Stream Channels, Alicia S. Arrigoni, Geoffrey C. Poole, Leal A. K. Mertes, Scott J. O'Daniel, William W. Woessner, Steven A. Thomas

School of Natural Resources: Faculty Publications

We monitored summertime base flow water temperatures of hyporheic discharge to surface water in main, side, and spring channels located within the bank-full scour zone of the gravel- and cobble-bedded Umatilla River, Oregon, USA. Diel temperature cycles in hyporheic discharge were common, but spatially variable. Relative to the main channel’s diel cycle, hyporheic discharge locations typically had similar daily mean temperatures, but smaller diel ranges (compressed by 2 to 6°C) and desynchronized phases (offset by 0 to 6 h). In spring channels (which received only hyporheic discharge), surface water diel cycles were also compressed (by 2 to 6°C) and desynchronized …

Estimation Of Net Ecosystem Carbon Exchange For The Conterminous United States By Combining Modis And Ameriflux Data, Jingfeng Xiao, Qianlai Zhuang, Dennis D. Baldocchi, Beverly E. Law, Andrew D. Richardson, Jiquan Chen, Ram Oren, Gregory Starr, Asko Noormets, Siyan Ma, Shashi Verma, Sonia Wharton, Steven C. Wofsy, Paul V. Bolstad, Sean P. Burns, David R. Cook, Peter S. Curtis, Bert G. Drake, Matthias Falk, Marc L. Fischer, David R. Foster, Lianhong Gu, Julian L. Hadley, David Y. Hollinger, Gabriel G. Katul, Marcy Litvak, Timothy A. Martin, Roser Matamala, Steve Mcnulty, Tilden P. Meyers, Russell K. Monson, J. William Munger, Walter C. Oechel, Kyaw Tha Paw U, Hans Peter Schmid, Russell L. Scott, Ge Sun, Andrew E. Suyker, Margaret S. Torn

School of Natural Resources: Faculty Publications

Eddy covariance flux towers provide continuous measurements of net ecosystem carbon exchange (NEE) for a wide range of climate and biome types. However, these measurements only represent the carbon fluxes at the scale of the tower footprint. To quantify the net exchange of carbon dioxide between the terrestrial biosphere and the atmosphere for regions or continents, flux tower measurements need to be extrapolated to these large areas. Here we used remotely sensed data from the Moderate Resolution Imaging Spectrometer (MODIS) instrument on board the National Aeronautics and Space Administration’s (NASA) Terra satellite to scale up AmeriFlux NEE measurements to the …

Boom And Bust On The Great Plains: Déjà Vu All Over Again, Sandra Zellmer

Nebraska College of Law: Faculty Publications

Two books published in 2006 provide a compelling portrait of the "boom and bust" cycles that have plagued the Great Plains since European settlement. The Worst Hard Time: The Untold Story of Those Who Survived the Great American Dust Bowl and Ogallala Blue: Water and Life on the High Plains stand beside Mark Reisner's classic study of western water resources, Cadillac Desert, and Wallace Stegner's tribute to one of America's greatest conservationists, Crossing the Next Meridian: John Wesley Powell and the Second Opening of the West, as "must read" books for anyone who cares about the future of …

Science And Technology Policymaking: A Primer, Deborah D. Stine

Congressional Research Service Reports

Scientific and technical knowledge and guidance influences not just policy related to science and technology, but also many of today’s public policies as policymakers seek knowledge to enhance the quality of their decisions. Science and technology policy is concerned with the allocation of resources for and encouragement of scientific and engineering research and development, the use of scientific and technical knowledge to enhance the nation’s response to societal challenges, and the education of Americans in science, technology, engineering, and mathematics.

Science and engineering research and innovations are intricately linked to societal needs and the nation’s economy in areas such as …

Fire And Climate In The Inland Pacific Northwest: Integrating Science And Management, Rachel Clark

Joint Fire Science Program Briefs (2007-2012)

Climate is a vital force shaping much of life on Earth. People have long suspected a link between climate and susceptibility of forests to fire. But measuring such a relationship has been challenging without tools capable of taking into account climate, forest structure through space and time, and other variables. Managers and planners who make decisions to maintain forest health need an accurate understanding of how climate is linked to fire regimes, as well as tools to help them do it. Such tools would take complex information and allow it to be accessed in a straightforward and effective way. Don …

Beetles And Severe Fire: Who’S On First? A Century Of Disturbance In Colorado’S Subalpine Forests, Marjie Brown

Joint Fire Science Program Briefs (2007-2012)

Forests have evolved with and depend on natural cycles of wildfire, insect outbreaks, disease, and extreme weather for periodic rejuvenation. The subalpine forests of northwestern Colorado experienced an unusual sequence of disturbances in succession over the past 125 years. Severe wildfi res in 2002 were preceded by stand-replacing fi res a century before. These were followed by a record setting wind blowdown, subsequent salvage logging, and two separate bark beetle infestations. This study by University of Colorado researchers was the first to collectively analyze how a century of disturbances interacted with each other to shape ecosystem patterns and processes with …

The Cone Fire: A Chance Reckoning For Fuel Treatments, Lisa-Natalie Anjozian

Joint Fire Science Program Briefs (2007-2012)

In late September 2002, an accidental fire ignited on Blacks Mountain in the dry pine forest of the Cascade Range of northeastern California. The fire burned through the Blacks Mountain Experimental Forest where a large-scale, long-term study was already underway to test ecological responses to two different stand structures the scientists had created using various treatments: high diversity, with and without prescribed fire, and low diversity, with and without prescribed fire. The study was not originally designed to test the effects of severe wildfires. The Cone Fire created an opportunity to evaluate the effects of different treatments on tree survival …

Application Of A Geomorphic And Temporal Perspective To Wetland Management In North America, Loren M. Smith, Ned H. Euliss Jr., Douglas A. Wilcox, Mark M. Brinson

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

The failure of managed wetlands to provide a broad suite of ecosystem services (e.g., carbon storage, wildlife habitat, ground-water recharge, storm-water retention) valuable to society is primarily the result of a lack of consideration of ecosystem processes that maintain productive wetland ecosystems or physical and social forces that restrict a manager’s ability to apply actions that allow those processes to occur. Therefore, we outline a course of action that considers restoration of ecosystem processes in those systems where off-site land use or physical alterations restrict local management. Upon considering a wetland system, or examining a particular management regime, there are …

Long-Term Dynamics Of Leafy Spurge (Euphorbia Esula) And Its Biocontrol Agent, Flea Beetles In The Genus Aphthona, Diane L. Larson, James B. Grace, Jennifer L. Larson

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Three flea beetle species (Aphthona spp.), first introduced into North America in 1988, have come to be regarded as effective biological control organisms for leafy spurge (Euphorbia esula). The black flea beetles (Aphthona lacertosa and A. czwalinae) in particular have been shown to cause reductions in leafy spurge stem counts in the northern Great Plains, while the brown flea beetle (A. nigriscutis) has persisted and spread, but has not been found to be as effective at controlling leafy spurge. The ability of black flea beetles to control leafy spurge in any given year, …

Mountain-Prairie Region Fisheries Program Strategic Plan

United States Fish and Wildlife Service: Publications

This Mountain-Prairie Regional Fisheries Strategic Plan outlines where, within our Federal role, we will focus our efforts. It provides guidance to partners and the public about our priorities, mandates, and opportunities and to Congress and the Administration on future budgeting decisions.

Valentine National Wildlife Refuge 2008

United States Fish and Wildlife Service: Publications

INTRODUCTION

Valentine National Wildlife Refuge (NWR) was established on August 4, 1935 under the Migratory Bird Conservation Act by Executive Order 7142. The purpose of the refuge as stated in the executive order is “as a refuge and breeding ground for migratory birds and other wildlife.” Acquisition funding came from Duck Stamp sales and the Emergency Conservation Fund Of 1933.

The 71,772-acre Valentine NWR is located in the Sandhills of north-central Nebraska. The Sandhills contain the largest remaining stands of mid and tall grass native prairie left in North America. The refuge is a unique and ecologically important component of …

Discordant Patterns Of Genetic Variation At Two Chloroquine Resistance Loci In Worldwide Populations Of The Malaria Parasite Plasmodium Falciparum, Rajeev K. Mehlotra, Gabriel Mattera, Moses J. Bockarie, Jason D. Maguire, J. Kevin Baird, Yagya D. Sharma, Michael Alifrangis, Grant Dorsey, Philip J. Rosenthal, David J. Fryauff, James W. Kazura, Mark Stoneking, Peter A. Zimmerman

United States Navy: Publications

Mutations in the chloroquine resistance (CQR) transporter gene of Plasmodium falciparum (Pfcrt; chromosome 7) play a key role in CQR, while mutations in the multidrug resistance gene (Pfmdr1; chromosome 5) play a significant role in the parasite’s resistance to a variety of antimalarials and also modulate CQR. To compare patterns of genetic variation at Pfcrt and Pfmdr1 loci, we investigated 460 blood samples from P. falciparum infected patients from four Asian, three African, and three South American countries, analyzing microsatellite (MS) loci flanking Pfcrt (five loci [[1]40 kb]) and Pfmdr1 (either two …

Environmental Policy Aid Under Uncertainty, J. Mysiak, J. D. Brown, J. M. L. Jansen, N. W. T. Quinn

United States Department of Commerce: Staff Publications

Recent emphasis on uncertainty in environmental decision making reflects numerous changes in environmental science and policy making over the past few decades. Firstly, environmental policy problems increasingly involve large, interconnected and complex social choices. For example, climate change, ozone depletion, biodiversity loss, genetically-engineered crops, environment-related diseases and health risks involve large scale, long-term impacts, whose precise causes and consequences are often poorly understood. Given these uncertainties and the risk of irreversible environmental changes, different perspectives about the nature, policy implications, or even the existence of a problem, are inevitable (Rittel and Webber, 1973; Sarewitz, 2004).

Discrete Return Lidar-Based Prediction Of Leaf Area Index In Two Conifer Forests, Jennifer L. R. Jensen, Karen S. Humes, Lee A. Vierling, Andrew T. Hudak

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

Leaf area index (LAI) is a key forest structural characteristic that serves as a primary control for exchanges of mass and energy within a vegetated ecosystem. Most previous attempts to estimate LAI from remotely sensed data have relied on empirical relationships between field-measured observations and various spectral vegetation indices (SVIs) derived from optical imagery or the inversion of canopy radiative transfer models. However, as biomass within an ecosystem increases, accurate LAI estimates are difficult to quantify. Here we use lidar data in conjunction with SPOT5-derived spectral vegetation indices (SVIs) to examine the extent to which integration of both lidar and …

Sampling Of Malodorous Compounds In Air Using Stir Bar Sorbtive Extraction, John H. Loughrin, Nanh Lovanh, Arturo I. Quintanar, Rezaul Mahmood

High Plains Regional Climate Center: Staff Publications

Twisters, (poly)‐dimethylsiloxane‐coated magnetic stir bars, were used to measure compounds typical of swine manure malodor in air. In initial experiments, a time to achieve equilibrium was determined by preloading the stir bars with ten compounds with a range of volatilities and polarities and then monitoring their loss. The rate of loss was dependent on compound volatility, and the time for equilibrium to be attained varied widely, from 22 min for phenol to 210 min for skatole. To test whether the Twisters would respond linearly over a range of concentrations, the stir bars were placed in vented jars with solutions of …

Using Research And Engagement To Inform Policy Making, Alan J. Tomkins

University of Nebraska Public Policy Center: Publications

The University of Nebraska Public Policy Center specializes in policy-relevant research and engagement activities in five areas: 1. Access to Government Services
2. Application of Information Technology to Health
& Human Services Delivery Systems
3. Behavioral Health and Human Services
4. Public Participation in Policy Making
5. Water Resources

The Biological Viability Of The Most Endangered Marine Mammals And The Cost-Effectiveness Of Protection Programs

United States Marine Mammal Commission

No abstract provided.