Physical Sciences and Mathematics Commons^™

Ensemble Forecast Spread Induced By Soil Moisture Changes Over Mid-South And Neighbouring Midwestern Region Of The Usa, Arturo I. Quintanar, Rezaul Mahmood

School of Natural Resources: Faculty Publications

This study investigated the potential impact of soil moisture perturbations on the statistical spread of an ensemble forecast for three different synoptic events during the summer of 2006. Soil moisture was perturbed from a control simulation to generate a 12 member ensemble with six drier and six moister soils. The impacts on the near-surface atmospheric conditions and on precipitation were analysed. It was found, as previous studies have confirmed, that soil moisture can change the spatial and temporal distribution of precipitation and of the overlying circulation. It was found that regardless of the conditions in synoptic forcing, temperature, relative humidity …

Adaptive Management Of Bull Trout Populations In The Lemhi Basin, Andrew J. Tyre, James T. Peterson, Sarah J. Converse, Tiffany Bogich, Damien Miller, Max Post Van Der Burg, Carmen Thomas, Ralph Thompson, Jeri Wood, Donna C. Brewer, Michael C. Runge

School of Natural Resources: Faculty Publications

The bull trout Salvelinus confluentus, a stream-living salmonid distributed in drainages of the northwestern United States, is listed as threatened under the Endangered Species Act because of rangewide declines. One proposed recovery action is the reconnection of tributaries in the Lemhi Basin. Past water use policies in this core area disconnected headwater spawning sites from downstream habitat and have led to the loss of migratory life history forms. We developed an adaptive management framework to analyze which types of streams should be prioritized for reconnection under a proposed Habitat Conservation Plan. We developed a Stochastic Dynamic Program that identified optimal …

Characterizing The Performance Of Ecosystem Models Across Time Scales: A Spectral Analysis Of The North American Carbon Program Site-Level Synthesis, Michael C. Dietze, Rodrigo Vargas, Andrew D. Richardson, Paul C. Stoy, Alan G. Barr, Ryan S. Anderson, M. Altaf Arain, Ian T. Baker, T. Andrew Black, Jing M. Chen, Philippe Ciais, Lawrence B. Flanagan, Christopher M. Gough, Robert F. Grant, David Hollinger, R. Cesar Izaurralde, Christopher J. Kucharik, Peter Lafleur, Shugang Liu, Erandathie Lokupitiya, Yiqi Luo, J. William Munger, Changhui Peng, Benjamin Poulter, David T. Price, Daniel M. Ricciuto, William J. Riley, Alok Kumar Sahoo, Kevin Schaefer, Andrew E. Suyker, Hanqin Tian, Christina Tonitto, Hans Verbeeck, Shashi B. Verma, Weifeng Wang, Ensheng Weng

School of Natural Resources: Faculty Publications

Ecosystem models are important tools for diagnosing the carbon cycle and projecting its behavior across space and time. Despite the fact that ecosystems respond to drivers at multiple time scales, most assessments of model performance do not discriminate different time scales. Spectral methods, such as wavelet analyses, present an alternative approach that enables the identification of the dominant time scales contributing to model performance in the frequency domain. In this study we used wavelet analyses to synthesize the performance of 21 ecosystem models at 9 eddy covariance towers as part of the North American Carbon Program’s site-level intercomparison. This study …

Heritable Choice Of Colony Size In Cliff Swallows: Does Experience Trump Genetics In Older Birds?, Erin A. Roche, Charles R. Brown, Mary Bomberger Brown

School of Natural Resources: Faculty Publications

The variation in breeding colony size seen in populations of most colonial birds may reflect heritable choices made by individuals that are phenotypically specialized for particular social environments. Although a few studies have reported evidence for genetically based choice of group sizes in birds, we know relatively little about the extent to which animals potentially rely on experience versus innate preferences in deciding how many conspecifics to settle with at different times of their lives. We conducted a cross-fostering experiment in 1997–1998 on cliff swallows, Petrochelidon pyrrhonota, in southwestern Nebraska, USA, in which some individuals were reared in colonies …

Effect Of Passive Integrated Transponder Tag Implantation Site On Tag Retention, Growth, And Survival Of Two Sizes Of Juvenile Bluegills And Yellow Perch, Mark A. Kaemingk, Michael J. Weber, Paul R. Mckenna, Michael L. Brown

School of Natural Resources: Faculty Publications

Passive integrated transponder (PIT) tags are commonly used to monitor growth, habitat use, activity rates, and survival of individual fish. However, for successful completion of research objectives, the tags must be retained and must not affect fish growth or survival. We compared the effects of PIT tagging location on tag retention, growth, and survival of juvenile bluegills Lepomis macrochirus and yellowperch Perca flavescens. In total, 80 bluegills and 80 yellow perch from two size-classes (75–101 and 128–162 mm total length) were randomly assigned to a control or to one of three tagging location treatments: isthmus, body cavity, or dorsal musculature. …

Isolation By Distance Explains Genetic Structure Of Buggy Creek Virus, A Bird-Associated Arbovirus, Abinash Padhi, Amy T. Moore, Mary Bomberger Brown, Jerome E. Foster, Martin Pfeffer, Charles R. Brown

School of Natural Resources: Faculty Publications

Many of the arthropod-borne viruses (arboviruses) show extensive genetic variability and are widely distributed over large geographic areas. Understanding how virus genetic structure varies in space may yield insight into how these pathogens are adapted to and dispersed by different hosts or vectors, the relative importance of mutation, drift, or selection in generating genetic variability, and where and when epidemics or epizootics are most likely to occur. However, because most arboviruses tend to be sampled opportunistically and often cannot be isolated in large numbers at a given locale, surprisingly little is known about their spatial genetic structure on the local …

Stormwater Management: Terminology, Kathryn A. Pekarek, David P. Shelton, Kelly Feehan, Bobbi A. Holm

School of Natural Resources: Faculty Publications

Stormwater runoff is the result of precipitation that does not infiltrate into the soil. Rather, it flows over land areas or through storm drains to streams, rivers, and lakes. This water collects pollutants as it moves over streets, parking lots, driveways, and other surfaces. Typically, stormwater runoff is untreated before being discharged to surface water. The quantity and quality of stormwater runoff is directly related to land use; as more urban development occurs — especially impervious surfaces — greater amounts of water and contaminants are generated. According to the U.S. Environmental Protection Agency (EPA), highly urbanized areas generate over five …

Nest Survival Of Long-Billed Curlew In Nebraska, Cory J. Gregory, Stephen J. Dinsmore, Larkin A. Powell, Joel G. Jorgensen

School of Natural Resources: Faculty Publications

Long-billed Curlew Numenius americanus is an imperiled shorebird of western North America. Populations have declined dramatically in the last 150 years from the conversion of prairie to agriculture and it is now listed as a “Tier I at-risk” species in Nebraska. We undertook a 3-year project (2008–2010) to study the nest survival of Long-billed Curlews in Nebraska. We measured vegetation characteristics at each nest site (n = 14 nests) on two different spatial scales and used program MARK to model nest survival as a function of multiple covariates. Apparent nest survival was 29% (n = 4 successful nests) and our …

Nebraska's Tern And Plover Conservation Partnership -- A Model For Sustainable Conservation Of Threatened And Endangered Species, Mary Bomberger Brown, Mark E. Burbach, John Dinan, Renae J. Held, Ron J. Johnson, Joel G. Jorgensen, Jeanine Lackey, Jeffrey F. Marcus, Gina S. Matkin, Christine M. Thody

School of Natural Resources: Faculty Publications

Implementing successful conservation programs is critical if we are to protect the earth's most imperiled species. These programs must respect state and federal legal concerns as well as local economic and social interests, Here we describe a sustainable partnership approach to Piping Plover and Interior Least Tern conservation in Nebraska, USA. Partners include industry groups, federal, state, and local agencies, and non-governmental organizations. The factor that unifies all partners is a desire to accomplish cooperative threatened and endangered species conservation. We believe that implementing this sort of partnership model could be useful in addressing the protection of other species of …

The Influence Of Habitat And Environment On Smallmouth Bass (Micropterus Dolomieu) Nest Sites And Nest Success In Northern Lake Michigan, Mark A. Kaemingk, Alexander Clem, Tracy L. Galarowicz

School of Natural Resources: Faculty Publications

Information on smallmouth bass nesting ecology is lacking in northern Lake Michigan, despite available information for other Great Lakes ecosystems. Our objectives were to identify factors that influenced nesting sites and nest success in a smallmouth bass population in northern Lake Michigan. Temperature, substrate firmness, and lake bottom rugosity were measured and related to the number of smallmouth bass nests in four bays. We also investigated the role of temperature, effective fetch, and storms to explain nest success. Temperature appeared to be most important in explaining the number of nests and nest success; transects that experienced the greatest number of …

Movement Of Smallmouth Bass Within The Beaver Island Archipelago, Northern Lake Michigan., Mark A. Kaemingk, Tracy L. Galarowicz, John A. Clevenger, David F. Clapp

School of Natural Resources: Faculty Publications

Fish movement may vary across a wide array of aquatic ecosystems and may be related to the overall size of the system inhabited. We investigated movement of smallmouth bass in Lake Michigan because this information is lacking for larger systems. A total of 16 smallmouth bass were surgically implanted with ultrasonic transmitters within the Beaver Archipelago, northern Lake Michigan. During 2007–2008, a maximum of one location per individual was recorded daily during three specific tracking periods – pre-spawn, spawning, and post-spawn – to determine diurnal movement patterns. Movement was evaluated as site fidelity, minimum displacement rate,maximumexcursion rate, and distance from …

Exploring Spatial Distributions Of Larval Yellow Perch Perca Flavescens, Bluegill Lepomis Macrochirus, And Their Prey In Relation To Wind., Mark A. Kaemingk, Jeffrey C. Jolley, David W. Willis, Brian Ds Graeb

School of Natural Resources: Faculty Publications

The objectives of the present study were to determine if spatial differences existed between zooplankton, larval yellow perch Perca flavescens and bluegill Lepomis macrochirus (length, LT) in Pelican Lake (332 ha), NE, U.S.A. It was hypothesized that wind could act as a transport mechanism for larval fishes in this shallow lake, because strong winds are common at this geographic location. Potential spatial differences were explored, relating to zooplankton densities, size structure and densities of larval P. flavescens and L. macrochirus. Density differences (east v. west side of the lake) were detected for small- (two occasions), medium- (two occasions) and large-sized …

Design Of An Underwater Telemetry Antenna For Locating And Retrieving Submerged Radiocollars, Stephen L. Webb, Joshua A. Gaskamp, Kenneth L. Gee, Stephen Demarais, Andrew R. Little

School of Natural Resources: Faculty Publications

Radiocollars represent a significant investment of financial resources, particularly global positioning system (GPS) collars, and loss of data imposes analytical limitations from reduced sample sizes. Radiocollars on large, terrestrial mammals are seldom lost in the water. However, several instances in Oklahoma, USA necessitated a reliable and cost-effective technique for retrieving GPS collars from underwater to salvage the financial investment and data. We designed an underwater telemetry antenna to find and retrieve collars in ≤ 3 m of water. We describe field simulations under varying environmental and water conditions, and provide a list of materials along with instructions and considerations for …

Discovering Native Bees, Alison P. Stevens

School of Natural Resources: Faculty Publications

No abstract provided.

A Calibration-Free Evapotranspiration Mapping (Cremap) Technique, Jozsef Szilagyi, Janos Jozsa, Akos Kovacs

School of Natural Resources: Faculty Publications

No abstract provided.

A Calibration-Free Evapotranspiration Mapping Technique For Spatially-Distributed Regional-Scale Hydrologic Modeling, Jozsef Szilagyi, Akos Kovacs

School of Natural Resources: Faculty Publications

No abstract provided.

Metageographic Communities: A Geographic Model Of Demassified Societies, K. Nashleanas

School of Natural Resources: Faculty Publications

No abstract provided.

Numerical Validation Of A Diurnal Streamflow-Pattern-Based Evapotranspiration Estimation Method, Zoltan Gribovszki, Peter Kalicz, Jozsef Szilagyi

School of Natural Resources: Faculty Publications

No abstract provided.

Comment On Interference Of River Level Changes On Riparian Zone Evapotranspiration Estimates From Diurnal Groundwater Level Fluctuations By Zhu Et Al., Jozsef Szilagyi, Zoltan Gribovszki, Peter Kalicz

School of Natural Resources: Faculty Publications

No abstract provided.

Discovering Native Bees, Alison P. Stevens

School of Natural Resources: Faculty Publications

NATURAL SYSTEMS PROVIDE humans with a variety of services essential to our survival. Ecosystem services such as climate regulation, water purification, oxygen production, waste treatment and detoxification, flood prevention, and pollination are provided at no cost, yet their true value is immeasurable. In our economydriven world, these systems are often taken for granted, and as a consequence many are in peril. Understanding their role is a critical first step towards ensuring that they endure. Pollination, the process of moving pollen grains from one flower to another to stimulate fruit and seed production, is among the easiest of these services to …

A Review Of Interior Least Tern And Piping Plover Management, Conservation, And Recovery On The Lower Platte River, Nebraska, Mary Bomberger Brown, Joel G. Jorgensen, Sonya E. Steckler, Melissa J. Panella, W. Ross Silcock

School of Natural Resources: Faculty Publications

SUMMARY

The Lower Platte River in eastern Nebraska provides many resources for wildlife and a variety of stakeholders. This river and its major tributaries contain important nesting habitat for two state and federally-listed bird species, the Interior Least Tern (endangered; Sternula antillarum athalassos) and the Northern Great Plains Piping Plover (threatened; Charadrius melodus). Both species nest on bare or sparsely-vegetated expanses of sand in natural and human-created habitat, which occur in and along river channels; the Lower Platte River system is critical for the survival and recovery of both species.

The Lower Platte River in eastern Nebraska provides …

Variations In North American Summer Precipitation Driven By The Atlantic Multidecadal Oscillation, Qi Hu, Song Feng, Robert J. Oglesby

School of Natural Resources: Faculty Publications

Understanding the development and variation of the atmospheric circulation regimes driven by the Atlantic multidecadal oscillation (AMO) is essential because these circulations interactwith other forcings on decadal and interannual time scales. Collectively, they determine the summer (June, July, and August) precipitation variations for NorthAmerica. In this study, a general circulation model (GCM) is used to obtain such understanding, with a focus on physical processes connecting the AMO and the summertime precipitation regime change in NorthAmerica. Two experimental runs are conducted with sea surface temperature (SST) anomalies imposed in the North Atlantic Ocean that represent the warm and cold phases of …

Intense Natural Selection On Morphology Of Cliff Swallows (Petrochelidon Pyrrhonota) A Decade Later: Did The Population Move Between Adaptive Peaks? Sélection Naturelle Intensive Sur La Morphologie De Petrochelidon Pyrrhonota Une Décennie Plus Tard: La Population S’Est-Elle Déplacée Entre Deux Pics Adaptatifs?, Mary Bomberger Brown, Charles R. Brown

School of Natural Resources: Faculty Publications

Unusual climatic events often lead to intense natural selection on organisms. Whether episodic selection events result in permanent microevolutionary changes or are reversed by opposing selection pressures at a later time is rarely known, because most studies do not last long enough to witness rare events and document their aftermath. In 1996, unusually cold and wet weather in southwestern Nebraska led to the deaths of thousands of Cliff Swallows (Petrochelidon pyrrhonota) over a 6-day period. Survivors were skeletally larger, with shorter wings and tails, and had less asymmetry in wing length than those that died. We determined trajectories of morphological …

Spectral Data-Based Estimation Of Soil Heat Flux, Ramesh K. Singh, Ayse Kilic, Elizabeth Walter-Shea, Shashi B. Verma, Andrew E. Suyker

School of Natural Resources: Faculty Publications

Numerous existing spectral‐based soil heat flux (G) models have shown wide variation in performance for maize and soybean cropping systems in Nebraska, indicating the need for localized calibration and model development. The objectives of this article are to develop a semi‐empirical model to estimate G from a normalized difference vegetation index (NDVI) and net radiation (R_n) for maize (Zea mays L.) and soybean (Glycine max L.) fields in the Great Plains, and present the suitability of the developed model to estimate G under similar and different soil and management conditions. Soil heat fluxes measured in both …

2011 Interior Least Tern And Piping Plover Monitoring, Research, Management, And Outreach Report For The Lower Platte River, Nebraska, Mary Bomberger Brown, Joel G. Jorgensen, Lauren R. Dinan

School of Natural Resources: Faculty Publications

This document reports on our monitoring, research, management, and outreach activities during the past 12 months (2011). 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 outreach in Nebraska. While the focus of our work is the …

Modeling Gross Primary Production Of Irrigated And Rain-Fed Maize Using Modis Imagery And Co2 Flux Tower Data, Joshua L. Kalfas, Xiangming Xiao, Diana X. Vanegas, Shashi B. Verma, Andrew E. Suyker

School of Natural Resources: Faculty Publications

Abstract

Information on gross primary production (GPP) of maize croplands is needed for assessing and monitoring maize crop conditions and the carbon cycle. A number of studies have used the eddy covariance technique to measure net ecosystem exchange (NEE) of CO₂ between maize cropland fields and the atmosphere and partitioned NEE data to estimate seasonal dynamics and interannual variation of GPP in maize fields having various crop rotation systems and different water management practices. How to scale up in situ observations from flux tower sites to regional and global scales is a challenging task. In this study, the Vegetation …

Impacts Of Irrigation On Dry Season Precipitation In India, Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.

Soil Moisture: A Central And Unifying Theme In Physical Geography, Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.

Heat Flux Measurements And Modeling Of Malodorous Compounds Above An Anaerobic Swine Lagoon, Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.

Land Use/Land Cover Changes And Climate: Modeling Analysis And Observational Evidence, Roger A. Pielke Sr., Andy Pitman, Dev Niyogi, Rezaul Mahmood, Clive Mcalpine, Faisal Hossain, Kees Klein Goldewijk, Udaysankar S. Nair, Richard Betts, Souleymane Fall, Markus Reichstein, Pavel Kabat, Nathalie De Noblet

School of Natural Resources: Faculty Publications

This article summarizes the changes in landscape structure because of human land management over the last several centuries, and using observed and modeled data, documents how these changes have altered biogeophysical and biogeochemical surface fluxes on the local, mesoscale, and regional scales. Remaining research issues are presented including whether these landscape changes alter large-scale atmospheric circulation patterns far from where the land use and land cover changes occur. We conclude that existing climate assessments have not yet adequately factored in this climate forcing. For those regions that have undergone intensive human landscape change, or would undergo intensive change in the …