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Plant Macrofossils Analysis From Steregoiu Nw Romania: Taphonomy, Representation, And Comparison With Pollen Analysis, Angelica N. Feurdean, Ole Bennike

Studia UBB Geologia

This paper presents the results of macrofossil analysis from the Steregoiu sequence in the Gutaiului Mountains covering the last 8,000 cal BP. The studied peat deposit is characterized by abundant macrofossils. Their diversity is, however, low with most macrofossils coming from plants that grew on the mire and in the forest surrounding the basin (Carex spp., Cyperus sp., Urtica dioica, Potentilla erecta, Filipendula ulmaria, Rubus idaeus, Lycopus europaeus). The concentration of Picea abies macrofossils correlates partially well with its pollen percentages, and only when it has been present on the bog surface. The absence of macrofossils from deciduous trees, which …

Kernel Density Estimation Of Traffic Accidents In A Network Space, Zhixiao Xie, Jun Yan

Earth, Environmental, and Atmospheric Sciences Faculty Publications

A standard planar Kernel Density Estimation (KDE) aims to produce a smooth density surface of spatial point events over a 2-D geographic space. However, the planar KDE may not be suited for characterizing certain point events, such as traffic accidents, which usually occur inside a 1-D linear space, the roadway network. This paper presents a novel network KDE approach to estimating the density of such spatial point events. One key feature of the new approach is that the network space is represented with basic linear units of equal network length, termed lixel (linear pixel), and related network topology. The use …

Phylogeographical Structure And Evolutionary History Of Two Buggy Creek Virus Lineages In The Western Great Plains Of North America, Abinash Padhi, Amy T. Moore, Mary Bomberger Brown, Jerome E. Foster, Martin Pfeffer, Kathryn P. Gaines, Valerie A. O'Brien, Stephanie A. Strickler, Allison E. Johnson, Charles R. Brown

School of Natural Resources: Faculty Publications

Buggy Creek virus (BCRV) is an unusual arbovirus within the western equine encephalitis complex of alphaviruses. Associated with cimicid swallow bugs (Oeciacus vicarius) as its vector and the cliff swallow (Petrochelidon pyrrhonota) and house sparrow (Passer domesticus) as its amplifying hosts, this virus is found primarily in the western Great Plains of North America at spatially discrete swallow nesting colonies. For 342 isolates collected in Oklahoma, Nebraska, Colorado, and North Dakota, from 1974 to 2007, we sequenced a 2076 bp region of the 26S subgenomic RNA structural glycoprotein coding region, and analyzed phylogenetic relationships, …

Non-Blackbird Avian Occurrence And Abundance In North Dakota Sunflower Fields, Dionn A. Schaaf, George M. Linz, Curt Doetkott, Mark W. Lutman, William J. Bleier

The Prairie Naturalist

Sunflower fields are well-documented as foraging habitat for fallmigrating blackbirds (Family Icteridae). There is, however, a paucity of information on the use of sunflower fields by non-blackbirds. We assessed non-blackbird use of 12 ripening sunflower fields in the Prairie Pothole Region of central North Dakota. From mid-August to mid-October 2000, we counted 4,129 individual birds, consisting of 22 families and 61 species, in the sample fields and within 5 m of the field edges. We saw the largest number of birds from 18 September to 27 September. The Family Emberizidae (sparrows) accounted for 26% of the species and 20% of …

Variation Of The Martian Ionospheric Electron Density From Mars Express Radar Soundings, D. D. Morgan, D. A. Gurnett, D. L. Kirchner, Jane L. Fox, E. Nielsen, J. J. Plaut

Physics Faculty Publications

The Mars Advanced Radar for Subsurface and Ionospheric Sounding aboard Mars Express has been in operation for over 2 years. Between 14 August 2005 and 31 July 2007, we obtain 34,492 ionospheric traces, of which 14,060 yield electron density profiles and 12,291 yield acceptable fits to the Chapman ionospheric model. These results are used to study the Martian ionosphere under changing conditions: the presence or absence of solar energetic particles, solar EUV flux, season, solar zenith angle, and latitude. The 2-year average subsolar maximum electron density n ₀ is 1.62 × 10⁵ cm⁻³, the average subsolar electron …

Estimating Soil Seed Bank Characteristics In Ponderosa Pine Forests Using Vegetation And Forest-Floor Data, Scott R. Abella, Judith D. Springer

Public Policy and Leadership Faculty Research

Soil seed banks are important for vegetation management because they contain propagules of species that may be considered desirable or undesirable for site colonization after management and disturbance events. Knowledge of seed bank size and composition before planning management activities facilitates proactive management by providing early alerts of exotic species presence and of abilities of seed banks to promote colonization by desirable species. We developed models in ponderosa pine (Pinus ponderosa) forests in northern Arizona to estimate the size and richness of mineral soil seed banks using readily observable vegetation and forestfloor characteristics. Regression models using three or fewer predictors …

Inside Unlv, Diane Russell, Shane Bevell, Michelle Mouton, Erin O'Donnell, Mamie Peers, Grace Russell, Deana Waddell

Inside UNLV

No abstract provided.

The Contribution Of Advective Fluxes To Net Ecosystem Exchange In A High-Elevation, Subalpine Forest, Chuixiang Yi, Dean E. Anderson, Andrew A. Turnipseed, Sean P. Burns, Jed P. Sparks, David I. Stannard, Russell K. Monson

Publications and Research

The eddy covariance technique, which is used in the determination of net ecosystem CO₂ exchange (NEE), is subject to significant errors when advection that carries CO₂ in the mean flow is ignored. We measured horizontal and vertical advective CO₂ fluxes at the Niwot Ridge AmeriFlux site (Colorado, USA) using a measurement approach consisting of multiple towers. We observed relatively high rates of both horizontal (F_hadv) and vertical (F_vadv) advective fluxes at low surface friction velocities (u_*) which were associated with downslope katabatic flows. We observed that F_hadv was confined to …

Loess Record Of The Pleistocene–Holocene Transition On The Northern And Central Great Plains, Usa, Joseph A. Mason, Xiaodong Miao, P.R. Hanson, William C. Johnson, Peter M. Jacobs, Ronald J. Goble

Department of Earth and Atmospheric Sciences: Faculty Publications

Various lines of evidence support conflicting interpretations of the timing, abruptness, and nature of climate change in the Great Plains during the Pleistocene–Holocene transition. Loess deposits and paleosols on both the central and northern Great Plains provide a valuable record that can help address these issues. A synthesis of new and previously reported optical and radiocarbon ages indicates that the Brady Soil, which marks the boundary between late Pleistocene Peoria Loess and Holocene Bignell Loess, began forming after a reduction in the rate of Peoria Loess accumulation that most likely occurred between 13.5 and 15 cal ka. Brady Soil formation …

Research On Bohai Bay Coal Ports In Coal Transportation From North To South China, Huan Xia

World Maritime University Dissertations

No abstract provided.

Benchmark Experiments For Higher-Order And Full-Stokes Ice Sheet Models (Ismip-Hom), F. Pattyn, L. Perichon, A. Aschwanden, B. Breuer, B. De Smedt, O. Gagliardini, G. H. Gudmundsson, R. C. A. Hindmarsh, A. Hubbard, Jesse V. Johnson, T. Kleiner, Y. Konovalov, C. Martin, A. J. Payne, D. Pollard, S. Price, M. Rückamp, F. Saito, O. Soucek, S. Sugiyama, T. Zwinger

Computer Science Faculty Publications

We present the results of the first ice sheet model inter comparison project for higher-order and full-Stokes ice sheet models. These models are compared and verified in a series of six experiments of which one has an analytical solution obtained from a perturbation analysis. The experiments are applied to both 2-D and 3-D geometries; five experiments are steady-state diagnostic, and one has a time dependent prognostic solution. All participating models give results that are in close agreement. A clear distinction can be made between higher-order models and those that solve the full system of equations. The full-Stokes models show a …

Defining A Fire Year For Reporting And Analysis Of Global Interannual Fire Variablility, Luigi Boschetti, David P. Roy

GSCE Faculty Publications

The interannual variability of fire activity has been studied without an explicit investigation of a suitable starting month for yearly calculations. Sensitivity analysis of 37 months of global MODIS active fire detections indicates that a 1-month change in the start of the fire year definition can lead, in the worst case, to a difference of over 6% and over 45% in global and subcontinental scale annual fire totals, respectively. Optimal starting months for analyses of global and subcontinental fire interannual variability are described. The research indicates that a fire year starting in March provides an optimal definition for annual global …

Erosion And Trail Building: A Case Study Of The East Tennessee State University Trail System., Joshua Callahan

Electronic Theses and Dissertations

Natural and accelerated erosion from trail users affects the sustainability of trail systems. Designing and building sustainable trail systems will greatly decrease the effect that erosion has on a trail. Trails that allow multiple types of users, such as hiking and mountain biking, must be able to sustain both groups. At East Tennessee State University the trail system was originally designed for hiking. Mountain bikers have become the main user group on the trail system leading to erosion problems on certain areas of the trail due to trail design flaws. The study seeks to identify the problem areas of trail …

Controls On Longitudinal Profiles In Headwater Rivers Of The Waipaoa Basin, North Island, New Zealand, David M. Livingston

All-Inclusive List of Electronic Theses and Dissertations

The longitudinal profiles of the adjacent Mangatu and Upper Waipaoa Rivers, of the Waipaoa basin of the North Island of New Zealand, differ in their form despite their similarity in size and that they flow over comparable bedrock. AdditionaJly, both basins have experienced an increase in sediment supply following deforestation during the 19th and 20th centuries. This research addresses how the deviations in the long profiles of the Mangatu and Upper Waipaoa Rivers have arisen and what effect the increased sediment loading has had on their form. Using methods similar to those of Hack (1957), who found that in same …

Geoarchaeological And Paleolandscape Reconstructions In The Lower Ohio River Valley: Late Wisconsin And Early Holocene Landforms In Knob Creek Bottom, Nathan Christopher Scholl

All-Inclusive List of Electronic Theses and Dissertations

This study examines a paleolandscape model that focuses on alluvial landforms that date to the Late Pleistocene and Early Holocene in Knob Creek bottom of the lower Ohio River valley. The study tests and refines a landscape model based on geoarchaeological data from the Caesars Archaeological Project. Analysis centers on the relationship between late Wisconsin and early Holocene Landform Sediment Assemblages (LSA), including early paleochannels. For this analysis a series of soil cores was extracted from the LSA understudy and described using standard USDA terminology. Additional analysis included particle size analysis using a hydrometer to determine textural composition of core …

Wavelet Analysis For Aboveground Biomass Estimate In Temperate Deciduous Forests, Xiaofang Wei

All-Inclusive List of Electronic Theses and Dissertations

The ever-increasing concentration of anthropogenic greenhouse gases (C02, CH4, and CFCs) has been identified as a likely (greater than 90% confidence) cause of the observed increase of global mean temperatures since the mid-20th century (IPCC, 2007). The effect of human-induced climate change could be unprecedented and far-reaching. Carbon sequestration into trees and forests is an effective and inexpensive way for mitigating the C02 level in the atmosphere. Hence, accurate measurement of biomass will be of great importance to global carbon cycle and climate change. This study performed a wavelet-based forest aboveground biomass estimation approach in a temperate deciduous forest, the …

Future Changes In Snowmelt-Driven Runoff Timing Over The Western Us, Sara A. Rauscher, Jeremy S. Pal, Noah S. Diffenbaugh, Michael M. Benedetti

Civil and Environmental Engineering Faculty Works

We use a high-resolution nested climate model to investigate future changes in snowmelt-driven runoff (SDR) over the western US. Comparison of modeled and observed daily runoff data reveals that the regional model captures the present-day timing and trends of SDR. Results from an A2 scenario simulation indicate that increases in seasonal temperature of approximately 3° to 5°C resulting from increasing greenhouse gas concentrations could cause SDR to occur as much as two months earlier than present. These large changes result from an amplified snow-albedo feedback driven by the topographic complexity of the region, which is more accurately resolved in a …

The Mayan Ice Cap: Glacial Geology And Paleoclimate Of The Northern Guatemalan Highlands, Alex Joseph Roy

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Sierra de los Cuchumatanes region of the northern Guatemalan highlands supported a large plateau ice cap with an area of -40 km2 along with a group of 5 cirque glaciers -1 to 2 km2 during the local last glacial maximum (LLGM). A comprehensive mapping reconstruction of the northern Guatemalan highlands is presented here, including glacial geology and an estimate of maximum ice limits from physical evidence and computer modeling. The glacial geologic map was produced via field mapping with global positioning system (GPS) surveying combined with aerial stereo photographic and topographic map analysis. This new field work on moraine …

The Return Of Russia: Energy's Superpower Or Potemkin Village?, Greg R. Bayes

Graduate Program in International Studies Theses & Dissertations

George Kennan's prediction of the Soviet Union's downfall may have, in retrospect, jinxed Russia on the one aspect that had historically worked in its favor: time. The confluence of time and space--brought about by an emphasis on territorial expansion-had greatly aided Russia when difficulties had rendered the variable of time indispensable. When confronted by the likes of Napoleon and Hitler, for example, Russia had at its disposal the luxury of always trading space for time. Although deprived of its empire, the issue of space is not an overarching concern for a Russia that today still spans from Vladivostok to St. …

Water Levels Effects On Overall Customer Satisfaction:, Crayton Pruitt

All Theses

Abstract The combination of hydroelectric power generation and the amount of precipitation results in fluctuating water levels on the United States Army Corps of Engineers: Lake Hartwell. Beginning in 2002 and continuing to the end of survey year 2004, water levels ranged from approximately ten feet below full pool to within half a foot under full pool. These fluctuations created difficulty for adjacent landowners to access sufficient water depths for recreational needs. The problems were magnified by a common perception that neighboring lakes', Lake Keowee and Lake Thurmond, water levels had not dropped as dramatically. This study examined the effects …

Implications For The Origin Of Grb 070201 From Ligo Observations, B. Abbott, R. Abbott, R. Adhikari, J. Agresti, P. Ajith, B. Allen, R. Amin, S. B. Anderson, W. G. Anderson, M. Arain, M. Araya, H. Armandula, M. Ashley, S. Aston, P. Aufmuth, C. Aulbert, S. Babak, S. Ballmer, H. Bantilan, B. C. Barish, C. Barker, D. Barker, B. Barr, P. Barriga, M. A. Barton, K. Bayer, J. Betzwieser, P. T. Beyersdorf, B. Bhawal, I. A. Bilenko, G. Billingsley, Tiffany Z. Summerscales

Faculty Publications

We analyzed the available LIGO data coincident with GRB 070201, a short-duration, hard-spectrum γ-ray burst (GRB) whose electromagnetically determined sky position is coincident with the spiral arms of the Andromeda galaxy (M31). Possible progenitors of such short, hard GRBs include mergers of neutron stars or a neutron star and a black hole, or soft γ-ray repeater (SGR) flares. These events can be accompanied by gravitational-wave emission. No plausible gravitational-wave candidates were found within a 180 s long window around the time of GRB 070201. This result implies that a compact binary progenitor of GRB 070201, with masses in the range …

Timing And Cause Of Water Level Fluctuations In Kluane Lake, Yukon Territory, Over The Past 5000 Years, Janice Brahney, John J. Clague, Brian Menounos, Thomas W. D. Edwards

Watershed Sciences Faculty Publications

We reconstructed late Holocene fluctuations of Kluane Lake in Yukon Territory from variations in bulk physical properties and carbon and nitrogen elemental and isotopic abundances in nine sediment cores. Fluctuations of Kluane Lake in the past were controlled by changes in climate and glaciers, which affected inflow of Slims and Duke rivers, the two largest sources of water flowing into the lake. Kluane Lake fluctuated within a narrow range, at levels about 25 m below the present datum, from about 5000 to 1300 cal yr BP. Low lake levels during this interval are probably due to southerly drainage of Kluane …

Using Local Data To Advance Quantitative Literacy, Stephen Sweet, Susanne Morgan, Danette Ifert Johnson

Numeracy

In this article we consider the application of local data as a means of advancing quantitative literacy. We illustrate the use of three different sources of local data: institutional data, Census data, and the National College Health Assessment survey. Our learning modules are applied in courses in sociology and communication, but the strategy of using local data can be integrated beyond these disciplinary boundaries. We demonstrate how these data can be used to stimulate student interests in class discussion, advance analytic skills, as well as develop capacities in written and verbal communication. We conclude by considering concerns that may influence …

The Economic Impact Of The Kentucky Green River Conservation Reserve Enhancement Program (Crep), Lorie B. Owen

Mahurin Honors College Capstone Experience/Thesis Projects

This study examines the impact of the Conservation Reserve Enhancement Program (CREP) on fourteen Kentucky counties. The CREP program is an advancement of the Conservation Reserve Program (CRP) which began nationally in 1985. The primary intention of both programs is to improve water quality and reduce soil erosion. Thus, in order to stimulate conservation efforts, farmers are given an opportunity to remove land from current production and still reap financial benefits. When CREP was introduced to Kentucky in 2002, the program provided far more lucrative incentives than the parent program. In 2007 CREP underwent an amendment process that broadened the …

Comparison Of Bacterial Diversity Within The Coral Reef Sponge, Axinella Corrugata, And The Encrusting Coral Erythropodium Caribaeorum, Jose V. Lopez, L. K. Ranzer, A. Ledger, B. Schoch, A. Duckworth, P. J. Mccarthy, R. G. Kerr

Marine & Environmental Sciences Faculty Articles

We compared the Caribbean reef sponge, Axinella corrugata, with the Caribbean reef coral, Erythropodium caribaeorum for differences in their resident microbial communities. This cursory survey of bacterial diversity applied 16S rRNA gene sequences. Over 100 culture-independent sequences were generated from five different Axinella 16S rRNA libraries, and compared with 69 cultured isolates. The cultureindependent 16S rDNA clones displayed a higher diversity of Proteobacteria, including “uncultured” or “unknown” representatives from the Deltaproteobacteria. Arcobacterium, and Cyanobacteria were also found. We have also confirmed that Axinella sponges appeared to host specific microbial symbionts, similar to the previously identified clones termed “OSO” …

Droughtscape, Summer 2008, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

VegDRI Expands West

Spring Rains Ease Drought But CA Still Dry

Scholar Donates Books

NDMC Welcomes Employees Bathke, Nothwehr

Latest Workshop Info Up

State Lawmakers to Focus on Drought Planning

Decadal Variation -- Clues to Droughts and Floods?

11th International Coral Reef Symposium Abstracts, Bernhard Riegl (Editor), Richard E. Dodge (Editor)

ICRS Conference Proceedings

No abstract provided.

Mapping The Multi-Tiered Impacts Of The Growth Of It Industries In India: A Combined Scale-And-Scope Externalities Perspective, Robert J. Kauffman, Ajay Kumar

Research Collection School Of Computing and Information Systems

Externalities occur among agglomerated firms. Scale externalities occur between firms in the same industry. Scope externalities occur when heterogeneous industries are collocated. Combined scale-and-scope externalities exist when the scale of one industry is beneficial to the growth of another collocated industry. In the Sein and Haridranath (2004) framework of information technology (IT) impacts on development, scale externalities correspond to second-order impacts, while combined scale and scope eternalities correspond to third-order impacts. We use an agglomeration perspective to explain the growth of IT industries in India. We study growth patterns of four specific IT industries: computer and peripheral equipment manufacturing, semiconductor …

Seasonal And Annual Variation In Body Condition Of Western Gray Whales Off Northeastern Sakhalin Island, Russia, Amanda L. Bradford, David W. Weller, Yulia V. Ivashchenko, Alexander M. Burdin, Robert L. Brownell Jr.

United States Department of Commerce: Staff Publications

The western gray whale population (Eschrichtius robustus) is critically endangered and its potential for recovery is uncertain. Along with other natural and anthropogenic threats, western gray whales are susceptible to nutritional stress, known from regular observations of individual whales in compromised body condition. Thus, the ability to visually quantify the relative body condition of free-ranging western gray whales and evaluate how this condition varies seasonally and annually is needed. A photo-identification study of western gray whales on their feeding ground off the northeastern coast of Sakhalin Island, Russia, produced a large dataset of digital, film, and video images …

Remote Sensing Solutions For Estimating Runoff And Recharge In Arid Environments, Adam M. Milewski

Dissertations

Efforts to understand and to quantify the interplay between precipitation, runoff, and recharge are often hampered by the paucity of appropriate monitoring systems. We developed methodologies for rainfall-runoff and groundwater recharge computations that heavily rely on observations extracted from a wide-range of global remote sensing data sets (TRMM, SSM/I, AVHRR, and AMSR-E,) using the arid Sinai Peninsula (SP; area: 61,000 km²) and the Eastern Desert (ED; area: 220,000 km²) of Egypt as our test sites. A two-fold exercise was conducted. Temporal remote sensing data (TRMM, AVHRR and AMSR-E) were extracted from global data sets over the …