Other Environmental Sciences Commons^™

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 …

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 …

Active Pharmaceutical Ingredients And Aquatic Organisms, Christian G. Daughton, Bryan W. Brooks

United States Environmental Protection Agency: Publications

The presence of active pharmaceuticals ingredients (APIs) in aquatic systems has led in recent years to a burgeoning literature examining environmental occurrence, fate, effects, risk assessment, and treatability of these compounds. The vast preponderance of studies aimed at identifying and quantifying contaminant residues in aquatic tissues have involved the conventional and legacy pollutants. Comparatively few studies have been targeted at APIs, primarily those that are lipophilic. Although APIs have received much attention as "emerging" contaminants of concern, it is important to recognize that traditional approaches to understand and predict exposure and effects of other environmental organic contaminant classes mayor may …

Long-Term Rice-Based Cropping System Effects On Near-Surface Soil Compaction, J. M. Motschenbacher, K. R. Brye, M. M. Anders

School of Natural Resources: Faculty Publications

No abstract provided.

Discovering Native Bees, Alison P. Stevens

School of Natural Resources: Faculty Publications

No abstract provided.

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 …

A Review Of Ethical Concepts And Moral Reasoning Integration Into Climate Change Curriculum, J. M. Dauer, C. Lettero, M. Ocana

School of Natural Resources: Faculty Publications

No abstract provided.

Improving Our Legacy: Incorporation Of Adaptive Management Into State Wildlife Action Plans, Joseph J. Fontaine

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The loss of biodiversity is a mounting concern, but despite numerous attempts there are few large scale conservation efforts that have proven successful in reversing current declines. Given the challenge of biodiversity conservation, there is a need to develop strategic conservation plans that address species declines even with the inherent uncertainty in managing multiple species in complex environments. In 2002, the State Wildlife Grant program was initiated to fulfill this need, and while not explicitly outlined by Congress follows the fundamental premise of adaptive management, ‘Learning by doing’. When action is necessary, but basic biological information and an understanding of …

Partially Acetylated Sugarcane Bagasse For Wicking Oil From Contaminated Wetlands, Seungoon Chung, Makram T. Suidan, Albert D. Venosa

United States Environmental Protection Agency: Publications

Sugarcane bagasse was partially acetylated to enhance its oil-wicking ability in saturated environments while holding moisture for hydrocarbon biodegradation. The water sorption capacity of raw bagasse was reduced fourfold after treatment, which indicated considerably increased hydrophobicity but not a limited capability to hold moisture for hydrocarbon biodegradation. Characterization results by Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD), and surface area analyzer suggested that treated bagasse exhibited enhanced hydrophobicity and surface area. Oil wicking test results indicate that treated bagasse is more effective in wicking oil from highly saturated environments than raw bagasse and suggest that application …

Time-Lapse Three-Dimensional Inversion Of Complex Conductivity Data Using An Active Time Constrained (Atc) Approach, M. Karaoulis, A. Revil, D. D. Werkema, B. J. Minsley, W. F. Woodruff, A. Kemna

United States Environmental Protection Agency: Publications

Induced polarization (more precisely the magnitude and phase of impedance of the subsurface) is measured using a network of electrodes located at the ground surface or in boreholes. This method yields important information related to the distribution of permeability and contaminants in the shallow subsurface. We propose a new time-lapse 3-D modelling and inversion algorithm to image the evolution of complex conductivity over time.We discretize the subsurface using hexahedron cells. Each cell is assigned a complex resistivity or conductivity value. Using the finite-element approach, we model the in-phase and out-of-phase (quadrature) electrical potentials on the 3-D grid, which are then …

Ddt And Other Organohalogen Pesticides In Aquatic Organisms, Nancy Beckvar, Guilherme R. Lotufo

United States Environmental Protection Agency: Publications

Organohalogen (OH) compounds are persistent hydrocarbon compounds containing a halogen group, often chlorine or bromine, that substitutes for hydrogen atoms in different positions in the hydrocarbon. They may occur naturally, but this chapter's focus is on synthetically produced compounds, mainly organochlorines, that were produced for use as pesticides. Nine OH compounds (aldrin, chlordane, dichlorodiphenyltrichloroethane [DDT], dieldrin, endrin, heptachlor, hexachlorobenzene, mirex, and toxaphene) are in the top 12 list of particularly toxic and persistent organic pollutants (POPs) identified by the Stockholm Convention treaty implemented in 2004 under the United Nations Environment Program (UNEP). More than 90 countries have signed on to …

The Role Of Demographic Compensation Theory In Incidental Take Assessments For Endangered Species, Conor P. Mcgowan, Mark R. Ryan, Michael C. Runge, Joshua J. Millspaugh, Jean Fitts Cochrane

United States Geological Survey: Staff Publications

Many endangered species laws provide exceptions to legislated prohibitions through incidental take provisions as long as take is the result of unintended consequences of an otherwise legal activity. These allowances presumably invoke the theory of demographic compensation, commonly applied to harvested species, by allowing limited harm as long as the probability of the species’ survival or recovery is not reduced appreciably. Demographic compensation requires some density-dependent limits on survival or reproduction in a species’ annual cycle that can be alleviated through incidental take. Using a population model for piping plovers in the Great Plains, we found that when the population …

Selenium In Birds, Harry M. Ohlendorf, Gary H. Heinz

United States Geological Survey: Staff Publications

Selenium (Se) is a metalloid trace element that birds and other wildlife need in small amounts for good health. The main purpose of this chapter is to interpret tissue concentrations of Se. However, because food is the main source of Se accumulation for birds and other wildlife, and because dietary concentrations for effects on bird reproduction have been reported, we also provide interpretive information on Se in the diet.

Se deficiencies in domestic poultry and livestock occur in some parts of the world and must be corrected by additions of Se to the diet. However, the range of dietary concentrations …

History Of Wildlife Toxicology And The Interpretation Of Contaminant Concentrations In Tissues, Barnett A. Rattner, Anton M. Scheuhammer, John E. Ellott

United States Geological Survey: Staff Publications

The detection and interpretation of contaminants in tissues of wildlife belongs to the field of toxicology, a scientific discipline with a long, intriguing, and illustrious history (reviewed by Hayes 1991, Gallo 2001, Gilbert and Hayes 2006, Wax 2006). We review its history briefly, to provide a context for understanding the use of tissue residues in toxicology, and to explain how their use has developed over time. Because so much work has been conducted on mercury, and dioxins and polychlorinated biphenyls (PCBs), separate case histories are included that describe the evolution of the use of tissue concentrations to assess exposure and …

Will Climate Change Alter Wildfire Behavior And Effects In Seasonally-Dry Wetlands?, Leda Kobziar Dr., Adam Watta Dr., J. Michael Camp Mr., Marissa Streiffel Ms., Alex Kattan Mr.

Joint Fire Science Program Research Project Reports

The effects of edge on ecosystems is well documented on animal and plant species, as well as a number of ecosystem attributes. A substantial determinant of ecological edge effects is the effect of edge on microclimate parameters such as temperature and humidity. These effects have been described in detail in upland communities, but not in wetland forests. Of particular interest is whether hydrologic influence trumps edge effect; in other words, does the influence of inundation create a hydrologic “switch” that overwhelms edge effect? In a landscape with numerous wetland forest patches subject to seasonal hydrologic fluctuations, I measured microclimate in …

Vegetation Impacts Of Recurring Fires On Sagebrush Ecosystems In Washington: Implications For Conservation And Rehabilitation, J. D. Bakker, P. W. Dunwiddie, S. A. Hall, J. R. Evans, G, M. Davies, E. Detterweiler-Robinson

Joint Fire Science Program Research Project Reports

Thousands of hectares of high quality sagebrush shrub-steppe burned in south-central Washington in 2000 and 2007, particularly on the Arid Lands Ecology Reserve (ALE) on the Hanford Reach National Monument. Extensive rehabilitation efforts took place on ALE to control invasive species and establish native species following each of these fires. Permanent vegetation monitoring plots were established throughout this area in the mid-1990s, remonitored in 2001-2004, and monitored again in 2009-2010. This combination of rehabilitation treatments and monitoring provided a unique opportunity to better understand the individual and cumulative effects of recurring fires and restoration in this landscape. We investigated changes …

The Influence Of Prescribed Fire And Understory Fuels Mastication On Soil Carbon Respiration Rates In Flatwoods Forests, Leda Kobziar, David Godwin, Michael Camp, Dawn Mckinstry, Marissa Steifel, Alex Kattan, Daniel Godwin

Joint Fire Science Program Research Project Reports

Soil CO2 efflux (Rs) is a significant flux of carbon dioxide from ecosystem soils to the atmosphere and is a critical component of the total ecosystem carbon budget. Rs fluxes are comprised of autotrophic (Ra) sources of CO2 produced by plant roots and associated rhizosphere fungi and heterotrophic (Rh) sources of CO2 produced by aerobic soil microbes. A variety of forest management activities, including prescribed fire and mechanical fuels mastication treatments have been shown to significantly influence Rs rates in forests of the Western United States (US), yet these relationships are not well known for southeastern US forests. Prescribed fire …

Comprehensive Fuels Treatment Pratices Guide For Mixed Conifer Forests: California, Central And Southern Rockies, And The Southwest, Alexander M. Evans, Rick G. Everett, Scott L. Stephens, James A. Youtz

Joint Fire Science Program Research Project Reports

The goal of this guide is to provide a resource for managers of mixed conifer forests of the Southwestern plateaus and uplands, the Central and Southern Rocky Mountains, the Sierra Nevada, and the Transverse and Peninsular Ranges in Southern California. Mixed conifer forests have different species, structures, and spatial patterns in these regions but, in general, we focus on forests with a mix of ponderosa or Jeffrey pine, Douglas-fir, true firs, and aspen. The guide includes a comprehensive review of historic conditions, past land use, natural fire regimes, impacts of altered fire regimes, and future prospects, given climate change, for …