Other Environmental Sciences Commons^™

Effects Of Climate And Landcover Change On Stream Discharge In The Ozark Highlands, Usa, Q. Steven Hu, Gary D. Willson, Xi Chen, Adnan Adnan

School of Natural Resources: Faculty Publications

Stream discharge of a watershed is affected and altered by climate and landcover changes. These effects vary depending on the magnitude and interaction of the changes, and need to be understood so that local water resource availability can be evaluated and socioeconomic development within a watershed be pursued and managed in a way sustainable with the local water resources. In this study, the landcover and climate change effects on stream discharge from the Jacks Fork River basin in the Ozark Highlands of the south-central United States were examined in three phases: site observation and data collection, model calibration and simulation, …

Some Concerns When Using Data From The Cooperative Weather Station Networks: A Nebraska Case Study, Hong Wu, Kenneth G. Hubbard, Jinsheng You

School of Natural Resources: Faculty Publications

In this study, daily temperature and precipitation amounts that are observed by the Cooperative Observer Program (COOP) were compared among geographically close stations. Hourly observations from nearby Automatic Weather Data Network (AWDN) stations were utilized to resolve the discrepancies between the observations during the same period. The statistics of maximum differences in temperature and precipitation between COOP stations were summarized. In addition, the quantitative measures of the deviations between COOP and AWDN stations were expressed by root-mean-square error, mean absolute error, and an index of agreement. The results indicated that significant discrepancies exist among the daily observations between some paired …

Steroid Hormone Levels Are Related To Choice Of Colony Size In Cliff Swallows, Charles R. Brown, Mary Bomberger Brown, Samrrah A. Raouf, Linda C. Smith, John C. Wingfield

School of Natural Resources: Faculty Publications

One hypothesis to explain the extensive variation in colony size seen in most
taxa is that individuals sort themselves among groups based on phenotypic characteristics
that correlate with their performance in groups of different sizes. We investigated how
baseline levels of the steroid hormones, corticosterone and testosterone, were associated
with choice of colony size and the likelihood of moving to a different site in later years
in colonially nesting Cliff Swallows (Petrochelidon pyrrhonota) in southwestern Nebraska,
USA, in 2000–2004. We sampled hormone levels of birds caught at colonies and, using
mark–recapture, monitored their movement and choice of colony size …

Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, Dana L. Hahn, Robert J. Dooling

United States Geological Survey: Staff Publications

The auditory brainstem response (ABR), a measure of neural synchrony, was used to estimate auditory sensitivity in the eastern screech owl (Megascops asio). The typical screech owl ABR waveform showed two to three prominent peaks occurring within 5 ms of stimulus onset. As sound pressure levels increased, the ABR peak amplitude increased and latency decreased. With an increasing stimulus presentation rate, ABR peak amplitude decreased and latency increased. Generally, changes in the ABR waveform to stimulus intensity and repetition rate are consistent with the pattern found in several avian families. The ABR audiogram shows that screech owls hear best between …

Visualizing Food And Farm, 2005 Joint Meetings Of The Agriculture, Food, And Human Values Society (Afhvs) And Association For The Study Of Food And Society (Asfs): Program And Abstracts, Jane Adams, Lorna Michael Butler, Richard P. Haynes, Laura B. Delind

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

Visualizing Food and Farm

2005 Joint Meetings of the Agriculture, Food, and Human Values Society (AFHVS) and Association for the Study of Food and Society (ASFS)

Program and Abstracts

June 9-12, 2005, Portland, Oregon, United States

Taxonomic Relationships Among Phenacomys Voles As Inferred By Cytochrome B, M. Renee Bellinger, Susan M. Haig, Eric D. Forsman, Thomas D. Mullins

United States Geological Survey: Staff Publications

Taxonomic relationships among red tree voles (Phenacomys longicaudus longicaudus, P. l. silvicola), the Sonoma tree vole (P. pomo), the white-footed vole (P. albipes), and the heather vole (P. intermedius) were examined using 664 base pairs of the mitochondrial cytochrome b gene. Results indicate specific differences among red tree voles, Sonoma tree voles, white-footed voles, and heather voles, but no clear difference between the 2 Oregon subspecies of red tree voles (P. l. longicaudus and P. l. silvicola). Our data further indicated a close relationship between tree voles and albipes, …

Comparison Of Individual And Pooled Sampling Methods For Detecting Bacterial Pathogens Of Fish, Sonia Mumford, Chris Patterson, Joy Evered, Ray Brunson, Jay Levine, Jim Winton

United States Geological Survey: Staff Publications

Examination of finfish populations for viral and bacterial pathogens is an important component of fish disease control programs worldwide. Two methods are commonly used for collecting tissue samples for bacteriological culture, the currently accepted standards for detection of bacterial fish pathogens. The method specified in the Office International des Epizooties Manual of Diagnostic Tests for Aquatic Animals permits combining renal and splenic tissues from as many as 5 fish into pooled samples. The American Fisheries Society (AFS) Blue Book/US Fish and Wildlife Service (USFWS) Inspection Manual specifies the use of a bacteriological loop for collecting samples from the kidney of …

Characterizing Moisture Regimes For Assessing Fuel Availability In North Carolina Vegetation Communities, Roberta A. Bartlette, James Reardon, Gary M. Curcio

Joint Fire Science Program Research Project Reports

In the southeastern United States prescription burning, fire danger rating and wildfire suppression strategies are constrained by limited knowledge of the influence of moisture content in live vegetation, organic soils, water table and weather. The interactive influence of these factors on fire behavior is not well studied. The 3+ year long study reported here was conducted to gain direct empirical understanding of seasonal fuel and soil moisture dynamics in shrub-dominated pocosin communities, in coastal Virginia and North Carolina, mixed hardwoods communities containing significant laurel and rhododendron understory fuels in western North Carolina and eastern Tennessee, and longleaf pine communities in …

Fuel Reduction And Restoration Of Pine/Hardwood Ecosystems Severely Impacted By The Recent Southern Pine Beetle (Dendroctonus Frontalis) Epidemic In The Southern Appalachians, James M. Vose, Katherine J. Elliott

Joint Fire Science Program Research Project Reports

As a result of this most recent SPB epidemic (1999-2003), thousands of hectares of dead pine trees have created wildfire-hazard conditions in the southern Appalachians. One of the challenges for land managers is how to return fire to these ecosystems after (1) nearly a decade of exclusion, and (2) the more recent SPB mortality enhanced fuel loads. Higher fuel loads have the potential to increase fire intensity and severity. At the extremes, fires of high intensity and severity can have a large effect on ecosystem structure and function. The objectives of our research were: (1) to quantify fuel load reduction …

Influence Of A Hailstreak On Boundary Layer Evolution, Zewdu T. Segele, David J. Stensrub, Ian C. Ratcliffe, Geoffrey M. Henebry

School of Natural Resources: Faculty Publications

Severe thunderstorms developed on 20 June 1997 and produced heavy precipitation, damaging winds, and large hail over two swaths in southeastern South Dakota. Calculations of fractional vegetation coverage (scaled from 0 to 1) based upon composite satellite data indicate that, within the hailstreak region, vegetation coverage decreased from 0.50 to near 0.25 owing to the damaging effects of hail on the growing vegetation. The northern edge of the larger hailstreak was located a few kilometers south of Chamberlain, South Dakota, a National Weather Service surface observation site. Hourly observations from Chamberlain and several nearby surface sites in South Dakota are …

Is Degradation A Major Problem In Semi-Desert Environments Of The Gobi Region In Southern Mongolia?, Karsten Wesche, Vroni Retzer

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

This paper tests predictions derived from the non-equilibrium theory of rangeland science. Data were collected in livestock enclosures situated in the relatively moist desert steppes of the Gobi Gurvan Saykhan region of southern Mongolia from 2000 to 2003. Plant community composition and species’ richness in enclosures showed clear differences between years, but these were equally strong in ungrazed controls. Thus, changes were mainly attributed to differences in precipitation between years as opposed to grazing, as no significant effects thereof were detected. This was also confirmed by data on above-ground standing biomass. This changed tremendously over the years, with differences between …

The Communicator, Volume 1, Issue 2, September 2005

The Communicator: News from the Nebraska Cooperative Fish and Wildlife Research Unit

People New Assistant Unit Leader Current Research Landowner Incentives Program (LIP) Amphibians in the Rainwater Basin Resilience in Ecosystems Cross-Scale Structure in Ecosystems Diversity and Ecological Functions: Pollination Future Research Projects Impact of White Perch on Walleye Spatial Risk Assessment of Invasive Species Impacts on Native Species in Nebraska Graduate Students (Donald (Don) Wardwell; Elizabeth (Beth) Forbus; Aaron Lotz) EVENTS Conferences/Meetings

Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, D. Caldwell Hahn, Robert J. Dooling

United States Geological Survey: Staff Publications

The auditory brainstem response (ABR), a measure of neural synchrony, was used to estimate auditory sensitivity in the eastern screech owl (Megascops asio). The typical screech owl ABR waveform showed two to three prominent peaks occurring within 5 ms of stimulus onset. As sound pressure levels increased, the ABR peak amplitude increased and latency decreased. With an increasing stimulus presentation rate, ABR peak amplitude decreased and latency increased. Generally, changes in the ABR waveform to stimulus intensity and repetition rate are consistent with the pattern found in several avian families. The ABR audiogram shows that screech owls hear best between …

An Assessment Of Key Aspects Of Warm And Cool Season Severe Flash Flooding In The Southern Appalachians, W. M. Baldwin, R. Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.

The Evolution Of A Warm Season Severe Eastern Kentucky Flash Flood, C. Henry, R. Mahmood, C. Smallcomb, M. Mclane, D. Champlin

School of Natural Resources: Faculty Publications

No abstract provided.

High Dispersal In A Frog Species Suggest That It Is Vulnerable To Habitat Fragmentation, W. Chris Funk, Allison E. Greene, Paul Stephen Corn, Fred W. Allendorf

United States Geological Survey: Staff Publications

Global losses of amphibian populations are a major conservation concern and have generated substantial debate over their causes. Habitat fragmentation is considered one important cause of amphibian decline. However, if fragmentation is to be invoked as a mechanism of amphibian decline, it must first be established that dispersal is prevalent among contiguous amphibian populations using formal movement estimators. In contrast, if dispersal is naturally low in amphibians, fragmentation can be disregarded as a cause of amphibian declines and conservation efforts can be focused elsewhere. We examined dispersal rates in Columbia spotted frogs (Rana luteiventris) using capture– recapture analysis …

Population Structure Of Columbia Spotted Frogs (Rana Luteiventris) Is Strongly Affected By The Landscape, W. Chris Funk, Michael S. Blouin, Paul Stephen Corn, Bryce A. Maxell, David S. Pilliod, Stephen Amish, Fred W. Allendorf

United States Geological Survey: Staff Publications

Landscape features such as mountains, rivers, and ecological gradients may strongly affect patterns of dispersal and gene flow among populations and thereby shape population dynamics and evolutionary trajectories. The landscape may have a particularly strong effect on patterns of dispersal and gene flow in amphibians because amphibians are thought to have poor dispersal abilities. We examined genetic variation at six microsatellite loci in Columbia spotted frogs (Rana luteiventris) from 28 breeding ponds in western Montana and Idaho, USA, in order to investigate the effects of landscape structure on patterns of gene flow. We were particularly interested in addressing …

Late-Holocene Flooding And Drought In The Northern Great Plains, Usa, Reconstructed From Tree Rings, Lake Sediments And Ancient Shorelines, M. D. Shapley, W. C. Johnson, D. R. Engstrom, W. R. Osterkamp

United States Geological Survey: Staff Publications

During the AD 1990s the Waubay Lakes complex in eastern South Dakota experienced historically unprecedented high water levels. Property damage from this flooding led to an examination of the occurrence of past pluvial episodes and their relation to climate. A lOOO-year hydroclimate reconstruction was developed from local bur oak (Quercus macrocarpa) tree-ring records and lake-sediment cores. Analysis of lake shoreline and drainage features provides late-Quaternary geomorphic context for this high-resolution record. Tree-ring width and shell geochemistry of the ostracode Candona rawsoni show marked coherence, indicating synchronous responses to moisture balance in vegetation and lake salinity; geomorphic evidence …

Atmospheric Circulation And Cyclone Frequency Variations Linked To The Primary Modes Of Greenland Snow Accumulation, Jeffrey C. Rogers, Deborah J. Bathke, Ellen Mosley-Thompson, Sheng-Hung Wang

School of Natural Resources: Faculty Publications

Data from 34 Greenland firn cores, extending from 1982 to 1996, are used to identify spatial accumulation variability patterns and their associated atmospheric circulation and cyclone frequencies. The first principal component, representing west-central Greenland accumulation, is correlated to NAO variability, having increased southwesterly (northeasterly) flow over that area during high (low) accumulation winters. The flow is linked to a relative increase in cyclone activity on the west central region of the ice sheet during high accumulation periods. The second principal component represents accumulation over southeastern Greenland where strong westerly flow leads to high accumulation and an increase in lee cyclones …

On The Uscrn Temperature System, Kenneth Hubbard, X. Lin, C.B. Baker

School of Natural Resources: Faculty Publications

In 2004 a new aspirated surface air temperature system was officially deployed nationally in the U.S. Climate Reference Network (USCRN) commissioned by the National Oceanic and Atmospheric Admin- istration. The primary goal of the USCRN is to provide future long-term and high-quality homogeneous observations of surface air temperature and precipitation that can be coupled to past long-term observations for the detection and attribution of present and future climate change. In this paper two precision air temperature systems are included for evaluating the new USCRN air temperature system based on a 1-yr side-by-side field comparison. The measurement errors of the USCRN …

Mesopredator Movement, Abundance, And Habitat Selection In The Rainwater Basins Of Nebraska, Christina J. Kocer

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.

Efficacy Of Offshore Breakwater Structures In A Eutrophic Midwestern Reservoir, Larry D. Pape

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.

Air Temperature Comparison Between The Mmts And The Uscrn Temperature Systems, K. G. Hubbard, X. Lin

School of Natural Resources: Faculty Publications

A new U.S. Climate Reference Network (USCRN) was officially and nationally commissioned by the Department of Commerce and the National Oceanic and Atmospheric Administration in 2004. During a 1-yr side-by-side field comparison of USCRN temperatures and temperatures measured by a maximum-minimum temperature system (MMTS), analyses of hourly data show that the MMTS temperature performed with biases: 1) a systematic bias–ambient-temperature-dependent bias and 2) an ambient-solar-radiation- and ambient-wind- speed-dependent bias. Magnitudes of these two biases ranged from a few tenths of a degree to over 1􏰈C compared to the USCRN temperatures. The hourly average temperatures for the USCRN were the dependent …

Structures And Dynamics Of Quasi-2d Mesoscale Convective Systems, Matthew D. Parker, Richard H. Johnson

School of Natural Resources: Faculty Publications

Recently, three distinct archetypes for midlatitude linear mesoscale convective systems (MCSs) have been identified. This article focuses on the fundamentals of two of these archetypes: convective lines with trailing stratiform (TS) precipitation and convective lines with leading stratiform (LS) precipitation. Both the TS and LS modes typically exhibit quasi-2D reflectivity patterns and quasi-2D environmental storm-relative wind fields. Ongoing work has revealed that there are three common flow structures for these quasi-2D MCSs: front-fed TS systems (which are sustained by front-to-rear storm-relative inflow), as well as front-fed LS and rear-fed LS systems (which are sustained by rear-to-front storm-relative inflow). This paper …

Notes And Correspondence Uncertainties Of Derived Dewpoint Temperature And Relative Humidity, X. Lin, Kenneth Hubbard

School of Natural Resources: Faculty Publications

This paper presents an evaluation of derived dewpoint temperature and derived relative humidity, in which the dewpoint temperature is calculated using measured ambient air temperature and measured relative humidity variables and the derived relative humidity is calculated from measured dewpoint temperature. The derived dewpoint temperature and relative humidity are calculated using algorithms provided by the World Meteorological Organization. The method of uncertainty analysis, provided by the National Institute of Standards and Technology, is applied to calculate the uncertainties of an indirect measurement of derived dewpoint temperature and derived relative humidity. The results from the uncertainty analyses of derived and observed …

Sensor And Electronic Biases/Errors In Air Temperature Measurements In Common Weather Station Networks*, X. Lin, Kenneth Hubbard

School of Natural Resources: Faculty Publications

The biases of four commonly used air temperature sensors are examined and detailed. Each temperature transducer consists of three components: temperature sensing elements, signal conditioning circuitry, and corresponding analog-to-digital conversion devices or dataloggers. An error analysis of these components was performed to determine the major sources of error in common climate networks. It was found that, regardless of microclimate effects, sensor and electronic errors in air temperature measurements can be larger than those given in the sensor manufacturer’s specifications. The root-sum-of-squares (RSS) error for the HMP35C sensor with CR10X datalogger was above 0.2􏰆C, and rapidly increases for both lower (􏰋􏰂20􏰆C) …

Variations In The Teleconnection Of Enso And Summer Rainfall In Northern China: A Role Of The Indian Summer Monsoon*, Song Feng, Qi Hu

School of Natural Resources: Faculty Publications

Observational studies have created a dilemma on how El Nin ̃o–Southern Oscillation (ENSO) may have affected interannual variations of summer rainfall in northern China; some suggested a consistent effect while others showed a complete lack of effect. This dilemma is resolved in this study, which shows that ENSO has affected the summer rainfall in northern China and the effect has varied at multidecadal scales. The question of how the ENSO teleconnection with northern China rainfall variation was established is addressed, and an answer pointing to the Indian summer monsoon as a ‘‘facilitator’’ connecting ENSO and northern China rainfall variation is …

Late Albian Dinosaur Tracks From The Cratonic (Eastern) Margin Of The Western Interior Seaway, Nebraska, Usa, R. M. Joeckel, J. M. Cunningham, R. G. Corner, P. L. Phillips, G. A. Ludvigson

School of Natural Resources: Faculty Publications

No abstract provided.

Accounting For Stream-Aquifer Interactions In The State-Space Discretization Of The Kmn-Cascade For Streamflow Forecasting, Jozsef Szilagyi

School of Natural Resources: Faculty Publications

No abstract provided.

Using Visitors Motivations To Provide Learning Opportunities At Water-Based Recreation Areas, Taylor V. Stein, Christine B. Denny, Lisa A. Pennisi

School of Natural Resources: Faculty Publications

No abstract provided.