Physical Sciences and Mathematics Commons^™

Integrating Remote Sensing And Geographic Information Systems, James W. Merchant, Sunil Narumalani

School of Natural Resources: Faculty Publications

Remote sensing and geographic information systems (GIS) comprise the two major components of geographic information science (GISci), an overarching field of endeavor that also encompasses global positioning systems (GPS) technology, geodesy and traditional cartography (Goodchild 1992, Estes and Star 1993, Hepner et al. 2005). Although remote sensing and GIS developed quasi-independently, the synergism between them has become increasingly apparent (Aronoff 2005). Today, GIS software almost always includes tools for display and analysis of images, and image processing software commonly contains options for analyzing ‘ancillary’ geospatial data (Faust 1998). The significant progress made in ‘integration’ of remote sensing and GIS has …

Remote Sensing Of Cropland Agriculture, M. Duane Nellis, Kevin P. Price, Donald Rundquist

School of Natural Resources: Faculty Publications

Remote sensing has long been used in monitoring and analyzing agricultural activities. Well prior to the first coining of the term ‘remote sensing’ in 1958 by Eveyln Pruitt of the U.S. Office of Naval Research (Estes and Jensen 1998), scientists were using aerial photography to complete soil and crop surveys associated with agricultural areas in the United States and other parts of the world (Goodman 1959). Most of such work in the 1930s involved general crop inventories by the U.S. Department of Agriculture and soil survey mapping as part of the work of the then U.S. Soil Conservation Service. With …

Non-Destructive Estimation Of Anthocyanins And Chlorophylls In Anthocyanic Leaves, Anatoly A. Gitelson, Olga B. Chivkunova, Mark N. Merzlyak

School of Natural Resources: Faculty Publications

The anthocyanin and chlorophyll contents in leaves provide valuable information about the physiological status of plants. Thus, there is a need for accurate, efficient, and practical methodologies to estimate these biochemical parameters of vegetation. In this study, we tested the performance and accuracy of several nondestructive, reflectance-based techniques for estimating anthocyanin and chlorophyll contents in leaves of four unrelated species, European hazel ( Corylus avellana ), Siberian dogwood ( Cornus alba = Swida alba ), Norway maple ( Acer platanoides ), and Virginia creeper ( Parthenocissus quinquefolia ), with widely variable pigment content and composition. An anthocyanin reflectance index, which …

Non-Destructive Detection Of Water Stress And Estimation Of Relative Water Content In Maize, Art I. Zygielbaum, Anatoly A. Gitelson, Timothy J. Arkebauer, Donald C. Rundquist

School of Natural Resources: Faculty Publications

Non-destructive estimation of leaf water content provides vital information about vegetation productivity. We report here on controlled seven day experiments using greenhouse-grown maize. Fifty plants were randomly assigned to two equal groups: water stressed and well watered. Spectroscopic, relative water content (RWC), and chlorophyll concentration measurements were made daily. Because water molecules absorb radiation in near- and middle-infrared, most efforts to sense water deficit remotely utilize infrared wavelengths. In these experiments, we identified a strong, systematic, and repeatable relationship between photosynthetically active radiation (PAR, 400-700 nm) albedo and leaf RWC. We show that visible spectrum reflectance provides a means to …

Nondestructive Estimation Of Anthocyanin Content In Grapevine Leaves, Mark R. Steele, Anatoly A. Gitelson, Donald C. Rundquist, Mark N. Merzlyak

School of Natural Resources: Faculty Publications

The anthocyanin (Anth) content in leaves provides valuable information about the physiological status of plants. Thus, there is a need for accurate, efficient, practical methodologies to estimate this biochemical parameter. Reflectance measurement is a means of quickly and nondestructively assessing leaf Anth content in situ. The objective of this study was to test the overall performance and accuracy of nondestructive techniques for estimating Anth content in grapevine leaves. Relationships were established between Anth content and four vegetation indices: NIR (near-infrared)/green, red/green, anthocyanin reflectance index (ARI, based on reflectances in bands within the green and the red-edge regions), and a modified …

A Bio-Optical Algorithm For The Remote Estimation Of The Chlorophyll-A Concentration In Case 2 Waters, Anatoly A. Gitelson, Daniela Gurlin, Wesley Moses, Tadd Barrow

School of Natural Resources: Faculty Publications

The objective of this work was to test the performance of a recently developed three-band model and its special case, a two-band model, for the remote estimation of the chlorophyll-a (chl-a) concentration in turbid productive case 2 waters. We specifically focused on (a) determining the ability of the models to estimate chl-a < 20 mg m⁻³, typical for coastal and estuarine waters, and (b) assessing the potential of MODIS and MERIS to estimate chl-a concentrations in turbid productive waters, using red and near-infrared (NIR) bands. Reflectance spectra and water samples were collected in 89 stations over lakes in …

Estimation Of Chlorophyll-A Concentration In Case Ii Waters Using Modis And Meris Data—Successes And Challenges, Wesley J. Moses, Anatoly A. Gitelson, V. Povazhnyy

School of Natural Resources: Faculty Publications

We present and discuss here the results of our work using MODIS (moderate resolution imaging spectroradiometer) and MERIS (medium resolution imaging spectrometer) satellite data to estimate the concentration of chlorophyll-a (chl-a) in reservoirs of the Dnieper River and the Sea of Azov, which are typical case II waters, i.e., turbid and productive. Our objective was to test the potential of satellite remote sensing as a tool for near-real-time monitoring of chl-a distribution in these water bodies. We tested the performance of a recently developed three-band model, and its special case, a two-band model, which use the …

Variability Of Anaerobic Animal Waste Lagoon Delta15N Source Signatures, Sadayappan Mariappan, Mary Exner Spalding, Glen E. Martin, Roy F. Spalding

School of Natural Resources: Faculty Publications

High ammonium-N concentrations derived from animal wastes stored and partially treated in earthen anaerobic lagoons at confined feeding facilities can seep to groundwater. δ¹⁵N-NH₄⁺ values from +2.0 to +59.1‰ in 13 lagoons complicate identification of lagoon seepage as well as land-applied lagoon effluent in ground and surface waters. The spectrum of δ¹⁵N values requires site-specific isotope characterization of the potential source. Feed and fresh manure and urine δ¹⁵N values indicate that most N isotopic fractionation occurs after excretion. Lagoon management clearly affects enrichment. δ¹⁵N-total Kjeldahl N (TKN) and δ^{15 …}

Long-Term Agricultural Land-Use Trends In Nebraska, 1866–2007, Tim L. Hiller, Larkin A. Powell, Tim D. Mccoy, Jeffrey J. Lusk

School of Natural Resources: Faculty Publications

Although landscape changes from anthropogenic causes occur at much faster rates than those from natural processes (e.g., geological, vegetation succession), human perception of such changes is often subjective, inaccurate, or nonexistent. Given the large-scale land-use changes that have occurred throughout the Great Plains, the potential impacts of land-use changes on ecological systems, and the insight gained from knowledge of land-use trends (e.g., to compare to wildlife population trends), we synthesized information related to land-use trends in Nebraska during 1866–2007. We discussed and interpreted known and potential causes of short- and long-term land-use trends based on agricultural and weather data; farm …

Spring Home Ranges Of White Bass In Irrigation Reservoirs Of The Republican River Basin, Nebraska, D. R. Martin, Larkin A. Powell, K. L. Pope

School of Natural Resources: Faculty Publications

Fishery biologists have documented small home ranges, relative to available habitat, for many littoral freshwater fishes. Home ranges for pelagic species, such as white bass Morone chrysops, are generally not well described, yet are thought to be large. We studied white bass movement using acoustic telemetry in two irrigation reservoirs of the Republican River basin in south-western Nebraska. Acoustic transmitters were implanted in fall of the previous year and tracking occurred a minimum of once per week throughout spring (mid-March to May) 2007 and 2008. Linear home ranges were calculated from observed locations of individual fish. Twelve of the …

Ecological Divergence Of Two Sympatric Lineages Of Buggy Creek Virus, An Arbovirus Associated With Birds, Charles R. Brown, Abinash Padhi, Amy T. Moore, Mary Bomberger Brown, Jerome E. Foster, Martin Pfeffer, Valerie A. O'Brien, Nicholas Komar

School of Natural Resources: Faculty Publications

Most arthropod-borne viruses (arboviruses) show distinct serological subtypes or evolutionary lineages, with the evolution of different strains often assumed to reflect differences in ecological selection pressures. Buggy Creek virus (BCRV) is an unusual RNA virus (Togaviridae, Alphavirus) that is associated primarily with a cimicid swallow bug (Oeciacus vicarius) as its vector and the Cliff Swallow (Petrochelidon pyrrhonota) and the introduced House Sparrow (Passer domesticus) as its amplifying hosts. There are two sympatric lineages of BCRV (lineages A and B) that differ from each other by .6% at the nucleotide level. Analysis of 385 …

2009 Interior Least Tern And Piping Plover Monitoring, Research, Management, And Outreach Report For The Lower Platte River, Nebraska, Mary Bomberger Brown, Joel G. Jorgensen

School of Natural Resources: Faculty Publications

This document reports on our monitoring, research, management, and outreach activities during the past 12 months (2009). We prepared it to inform our partners, cooperating agencies, funding sources, and other interested parties of our activities and to provide a preliminary summary of our results.

The Tern and Plover Conservation Partnership (TPCP), based at the University of Nebraska–School of Natural Resources, and the Nongame Bird Program (NBP), based at the Nebraska Game and Parks Commission (NGPC) work cooperatively on Interior Least Tern and Piping Plover monitoring, research, management, and education-outreach activities. While the proximate focus of our work is the Lower …

Incorporation Of Crop Phenology In Simple Biosphere Model (Sibcrop) To Improve Land-Atmosphere Carbon Exchanges From Croplands, Erandathie Lokupitiya, S. Denning, K. Paustian, I. Baker, K. Schaefer, Shashi B. Verma, T. Meyers, C. J. Bernacchi, Andrew E. Suyker, M. L. Fischer

School of Natural Resources: Faculty Publications

Croplands are man-made ecosystems that have high net primary productivity during the growing season of crops, thus impacting carbon and other exchanges with the atmosphere. These exchanges play a major role in nutrient cycling and climate change related issues. An accurate representation of crop phenology and physiology is important in land-atmosphere carbon models being used to predict these exchanges. To better estimate time-varying exchanges of carbon, water, and energy of croplands using the Simple Biosphere (SiB) model, we developed crop-specific phenology models and coupled them to SiB. The coupled SiBphenology model (SiBcrop) replaces remotely-sensed NDVI information, on which SiB originally …

Corrigendum To “Incorporation Of Crop Phenology In Simple Biosphere Model (Sibcrop) To Improve Land-Atmosphere Carbon Exchanges From Croplands” Published In Biogeosciences, 6, 969–986, 2009, Erandathie Lokupitiya, S. Denning, K. Paustian, I. Baker, K. Schaefer, Shashi B. Verma, T. Meyers, C. J. Bernacchi, Andrew E. Suyker, M. L. Fischer

School of Natural Resources: Faculty Publications

In the above mentioned manuscript a mistake in Fig. 11 occured. The corrected version of the figure is as follows.

A Century Of Climate Change For Fairbanks, Alaska, Gerd Wendler, Martha Shulski

School of Natural Resources: Faculty Publications

Climatological observations are available for Fairbanks, Interior Alaska, for up to 100 years. This is a unique data set for Alaska, insofar as it is of relatively high quality and without major breaks. Applying the best linear fit, we conclude that the mean annual temperature rose from -3.6°C to -2.2°C over the century, an increase of 1.4°C (compared to 0.8°C worldwide). This comparison clearly demonstrates the well-known amplification or temperature change for the polar regions. The observed temperature increase is neither uniform over the time period nor uniform throughout the course of a year. The winter, spring, and summer seasons …

Lithobates Catesbeianus (American Bullfrog) Predation On Cliff Swallows, Mary Bomberger Brown, Charles R. Brown

School of Natural Resources: Faculty Publications

During a 25-year study of Cliff Swallows (Petrochelidon pyrrhonota) in southwestern Nebraska, we observed Lithobates catesbeianus prey on, or attempt to prey on, Cliff Swallows. As we were mist-netting Cliff Swallows at a 10-nest colony on 7 July 1998, a L. catesbeianus attempted to eat a Cliff Swallow that was caught in the net.

Lichen Recovery Following Heavy Grazing By Reindeer Delayed By Climate Warming, David R. Klein, Martha Shulski

School of Natural Resources: Faculty Publications

Introduced reindeer, Rangifer tarandus, over exploited lichen-rich plant communities on St. Matthew Island in the Bering Sea. A die-off of the reindeer followed, exacerbated by extreme weather in 1964, resulting in extirpation of the reindeer. A similar pattern of removal of lichens as major components of plant communities has occurred following introductions of reindeer to other islands at high latitudes. By 1985, two decades following die-off of the reindeer, total lichen biomass was only 6% of that in similar plant communities on adjacent Hall Island, not reached by the reindeer. By 2005, 41 y after the reindeer die-off, lichen …

One-Pot Synthesis Of Anionic (Nitrogen) And Cationic (Sulfur) Codoped High-Temperature Stable, Visible Light Active, Anatase Photocatalysts, Suresh Pillai, Declan Mccormack, Steven Hinder, Pradeepan Periyat

Articles

No abstract provided.

Biwave Maps Into Manifolds, Yuan-Jen Chiang

Mathematics

We generalize wave maps to biwave maps. We prove that the composition of a biwave map and a totally geodesic map is a biwave map. We give examples of biwave nonwave maps. We show that if f is a biwave map into a Riemannian manifold under certain circumstance, then f is a wave map. We verify that if f is a stable biwave map into a Riemannian manifold with positive constant sectional curvature satisfying the conservation law, then f is a wave map. We finally obtain a theorem involving an unstable biwave map.

The Archaeology Of The Donner Party Review, Douglas D. Scott

United States National Park Service: Publications

Don Hardesty and his contributors have given us a new perspective on the Donner Party tragedy of 1846-1847. The Archaeology of the Donner Party is a concise and well-written account of the history, archaeological investigations, and reinterpretation of the events. This slim volume is a model of multidisciplinary research and a team approach to producing a publicly oriented archaeological interpretation of interesting events of our recent past.

Agate Fossil Beds National Monument: Geologic Resources Inventory Report, John Graham

United States National Park Service: Publications

This report accompanies the digital geologic map for Agate Fossil Beds National Monument in Nebraska, which the Geologic Resources Division produced in collaboration with its partners. It contains information relevant to resource management and scientific research. This document incorporates preexisting geologic information and does not include new data or additional fieldwork.

Formerly a working ranch in sparsely populated northwestern Nebraska, Agate Fossil Beds National Monument is one of the most important paleontological sites in the world for studying Miocene-age mammals and the evolving Miocene world which existed around 20 million years ago. The main bonebeds at Carnegie Hill and University …

Gravitational-Wave Memory Revisited: Memory From The Merger And Recoil Of Binary Black Holes, Marc Favata

Department of Physics and Astronomy Faculty Scholarship and Creative Works

Gravitational-wave memory refers to the permanent displacement of the test masses in an idealized (freely-falling) gravitational-wave interferometer. Inspiraling binaries produce a particularly interesting form of memory - the Christodoulou memory. Although it originates from nonlinear interactions at 2.5 post-Newtonian order, the Christodoulou memory affects the gravitational-wave amplitude at leading (Newtonian) order. Previous calculations have computed this non-oscillatory amplitude correction during the inspiral phase of binary coalescence. Using an "effective-one-body" description calibrated with the results of numerical relativity simulations, the evolution of the memory during the inspiral, merger, and ringdown phases, as well as the memory's final saturation value, are calculated. …

Nonlinear Gravitational-Wave Memory From Binary Black Hole Mergers, Marc Favata

Department of Physics and Astronomy Faculty Scholarship and Creative Works

Some astrophysical sources of gravitational waves can produce a "memory effect," which causes a permanent displacement of the test masses in a freely falling gravitational-wave detector. The Christodoulou memory is a particularly interesting nonlinear form of memory that arises from the gravitational-wave stress-energy tensor's contribution to the distant gravitational-wave field. This nonlinear memory contributes a nonoscillatory component to the gravitational-wave signal at leading (Newtonian-quadrupole) order in the waveform amplitude. Previous computations of the memory and its detectability considered only the inspiral phase of binary black hole coalescence. Using an "effective-one-body" (EOB) approach calibrated to numerical relativity simulations, as well as …

Stacked Search For Gravitational Waves From The 2006 Sgr 1900+14 Storm, B. P. Abbott, R. Abbott, R. Adhikari, P. Ajith, B. Allen, G. Allen, R. S. Amin, S. B. Anderson, W. G. Anderson, Rodica Martin

Department of Physics and Astronomy Faculty Scholarship and Creative Works

We present the results of a LIGO search for short-duration gravitational waves (GWs) associated with the 2006 March 29 SGR 1900+14 storm. A new search method is used, "stacking" the GW data around the times of individual soft-gamma bursts in the storm to enhance sensitivity for models in which multiple bursts are accompanied by GW emission. We assume that variation in the time difference between burst electromagnetic emission and potential burst GW emission is small relative to the GW signal duration, and we time-align GW excess power time-frequency tilings containing individual burst triggers to their corresponding electromagnetic emissions. We use …

An Assessment Of Epiphytic Lichens, Lichen Diversity And Environmental Quality In The Semi-Natural Woodlands Of Knocksink Wood Nature Reserve, Enniskerry, County Wicklow, Lenka Mulligan

Masters

This research work adapted and applied a recently developed method for assessing epiphytic lichen species diversity to the Irish semi-natural woodlands of Knocksink Wood Nature Reserve, Enniskerry, County Wicklow. The study focused on the differences that arise in relation to acidophilous oak woodland (Blechno-Quercetum petraeae) versus ash-hazel woodland (Corylo-Fraxinetum). The research also addressed differences in relation to the mixed oak-ash-hazel woodland located in Knocksink Wood and the neighbouring woodland at the Powerscourt Waterfall. The frequency of occurrence of lichen species on a defined portion of tree bark was used as an estimate of diversity and to evaluate the degree of …

Radiative Transfer Models Of The Galactic Center, Everett A. Schlawin

Honors Papers

This thesis discusses research being done to understand the inner parts of the Milky Way Galaxy. We already know that there are dense star clouds, a supermassive black hole, and a large bar structure, but much of the inner galaxy is shrouded in mystery. Dust absorption, for one thing, prevents us from seeing the galactic center directly with our eyes.

To help understand the elusive inner Milky Way, we examine radio telescope data taken in Antarctica by Oberlin College Professor Chris Martin. His gigahertz radio observations were already analyzed to help understand how gas funnels into the Milky Way's supermassive …

Keynote Address To The 2009 Designing An Effective Online Science Course Conference, Kristine M. Young

Vice President for Academic Services Scholarship

No abstract provided.

Oregon Mathematics Leadership Institute Project: Evaluation Results On Teacher Content Knowledge, Implementation Fidelity, And Student Achievement, D. Weaver, T. Dick

Journal of Mathematics and Science: Collaborative Explorations

The Oregon Mathematics Leadership Institute (OMLl) National Science Foundation Mathematics and Science Partnership project partners are Oregon State University, Portland State University, Teachers Development Group, and ten Oregon school districts. The primary activities of the project were a sequence of three intensive three-week residential institutes emphasizing mathematics content knowledge for teaching, collegial leadership, and the building of Professional Learning Communities. Teachers at all levels of grades K-12 participated together in the mathematics content courses. By the conclusion of the. third Summer Institute, teachers had shown significant improvements in mathematical content knowledge for teaching. Analysis of student achievement data in participating …

Origin Of The Anatase To Rutile Conversion Of Metal-Doped Tio2, Sa Li, Puru Jena

Physics Publications

Extensive calculations using density functional theory enable us to explain the origin of the surprising room-temperature conversion of anatase to rutile phase of TiO2 when doped with Co and Ni, but not with Cu. Contrary to earlier suggestion, neither high spin nor strain of the transition metals is found to be responsible for this phase conversion. The driving mechanism, instead, is attributed to the increased interaction between Co and Ni atoms forming a linear chain in the rutile phase. We predict that Cr and Mn which have even larger spins than Co and Ni cannot induce this phase conversion.

Magnetic Properties Of Transition-Metal-Doped Zn1−Xtxo (T=Cr, Mn, Fe, Co, And Ni) Thin Films With And Without Intrinsic Defects: A Density Functional Study, Qian Wang, Qiang Sun, Puru Jena, Y. Kawazoe

Physics Publications

Theoretical calculations based on density-functional theory and generalized gradient approximation have been carried out in studying the electronic structure and magnetic properties of transition-metal-doped Zn1−xTxO (T=Cr, Mn, Fe, Co, and Ni) (112¯0) thin films systematically with and without intrinsic point defects (e.g., vacancies and interstitials), and as function of concentration and distribution of dopants and vacancies. Using large supercells and geometry optimization without symmetry constraint, we are able to determine the sites that metal atoms prefer to occupy, their tendency to cluster, the preferred magnetic coupling between magnetic moments at transition-metal sites, and the effect of intrinsic point defects on …