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Articles 5731 - 5760 of 9826

Full-Text Articles in Natural Resources and Conservation

U.S. Department Of Energy Commercial Reference Building Models Of The National Building Stock, Michael Deru, Kristin Field, Daniel Studer, Kyle Benne, Brent Griffith, Paul Torcellini, Bing Liu, Mark Halverson, Dave Winiarski, Michael Rosenberg, Mehry Yazdanian, Joe Huang, Drury Crawley Feb 2011

U.S. Department Of Energy Commercial Reference Building Models Of The National Building Stock, Michael Deru, Kristin Field, Daniel Studer, Kyle Benne, Brent Griffith, Paul Torcellini, Bing Liu, Mark Halverson, Dave Winiarski, Michael Rosenberg, Mehry Yazdanian, Joe Huang, Drury Crawley

Publications (E)

The U.S. Department of Energy (DOE) Building Technologies Program has set the aggressive goal of producing marketable net-zero energy buildings by 2025. This goal will require collaboration between the DOE laboratories and the building industry. We developed standard or reference energy models for the most common commercial buildings to serve as starting points for energy efficiency research. These models represent fairly realistic buildings and typical construction practices. Fifteen commercial building types and one multifamily residential building were determined by consensus between DOE, the National Renewable Energy Laboratory, Pacific Northwest National Laboratory, and Lawrence Berkeley National Laboratory, and represent approximately two-thirds …


Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending January 31, 2011, Margaret N. Rees Jan 2011

Limnological Assistance For Lake Mead National Recreation Area: Quarterly Report, Period Ending January 31, 2011, Margaret N. Rees

Limnological Studies

Project 1

  • Technical assistance with the implementation of the Interagency Monitoring Action Plan (I-MAP) for Quagga Mussels is ongoing. During this quarter, analysis was completed for 21 adult/juvenile samples and analyses of the remaining samples are underway. A manuscript describing the I-MAP and its history, current recommended monitoring, and recommended future monitoring and a separate manuscript describing the I-MAP’s monitoring protocol were accepted for publication in the journal Aquatic Invasions. Two other manuscripts describing other aspects of the I-MAP program were published in Lake and Reservoir Management.

Project 2

  • Annual summary sheets are under development for the topics listed within …


2010 Vegetation Survey Of The Fort Niobrara National Wildlife Refuge (Final Report To The Nebraska Game And Parks Commission, U.S. Fish And Wildlife Service, And The Sandhills Prairie Refuge Association), Robert F. Steinauer Jan 2011

2010 Vegetation Survey Of The Fort Niobrara National Wildlife Refuge (Final Report To The Nebraska Game And Parks Commission, U.S. Fish And Wildlife Service, And The Sandhills Prairie Refuge Association), Robert F. Steinauer

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

Fort Niobrara National Wildlife Refuge (FNNWR) is located on the Niobrara River in north central Cherry County, NE. There is little detailed information available documenting the vegetation of FNNWR. Tolstead (1942) studied the grasslands of northern Cherry County, (including FNNWR) with a focus on describing the dominant species of grassland types and determining the relationships between vegetation distribution and environmental variables and management practices. Churchill et al (1988) described the vascular flora of The Nature Conservancy’s nearby Niobrara Valley Preserve. Fiest et al (2010) conducted vascular plant surveys on portions of the FNNWR in 2009 and compiled a partial vascular …


Synthesis Of Knowledge Of Extreme Fire Behavior: Volume I For Fire Managers, Paul Werth, Brian Potter, Craig Clements, Mark Finney, Scott Goodrick, Martin Alexander, Miguel Cruz, Jason Forthofer, Sara Mcallister Jan 2011

Synthesis Of Knowledge Of Extreme Fire Behavior: Volume I For Fire Managers, Paul Werth, Brian Potter, Craig Clements, Mark Finney, Scott Goodrick, Martin Alexander, Miguel Cruz, Jason Forthofer, Sara Mcallister

Faculty Publications, Meteorology and Climate Science

The National Wildfire Coordinating Group definition of extreme fire behavior (EFB) indicates a level of fire behavior characteristics that ordinarily precludes methods of direct control action. One or more of the following is usually involved: high rate of spread, prolific crowning/ spotting, presence of fire whirls, and strong convection column. Predictability is difficult because such fires often exercise some degree of influence on their environment and behave erratically, sometimes dangerously. Alternate terms include “blow up” and “fire storm.” Fire managers examining fires over the last 100 years have come to understand many of the factors necessary for EFB development. This …


Stormwater Management: Terminology, Kathryn A. Pekarek, David P. Shelton, Kelly Feehan, Bobbi A. Holm Jan 2011

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 Jan 2011

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 Jan 2011

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 Jan 2011

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 Jan 2011

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 Jan 2011

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 Jan 2011

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 …


A Calibration-Free Evapotranspiration Mapping (Cremap) Technique, Jozsef Szilagyi, Janos Jozsa, Akos Kovacs Jan 2011

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 Jan 2011

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 Jan 2011

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 Jan 2011

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 Jan 2011

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 Jan 2011

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 …


Landscape Structure, Groundwater Dynamics, And Soil Water Content Influence Soil Respiration Across Riparian–Hillslope Transitions In The Tenderfoot Creek Experimental Forest, Montana, Vincent J. Pacific, Diego Andrés Riveros-Iregui, Daniel L. Welsch, Howard E. Epstein Jan 2011

Landscape Structure, Groundwater Dynamics, And Soil Water Content Influence Soil Respiration Across Riparian–Hillslope Transitions In The Tenderfoot Creek Experimental Forest, Montana, Vincent J. Pacific, Diego Andrés Riveros-Iregui, Daniel L. Welsch, Howard E. Epstein

School of Natural Resources: Faculty Publications

Variability in soil respiration at various spatial and temporal scales has been the focus of much research over the last decade aimed to improve our understanding and parameterization of physical and environmental controls on this flux. However, few studies have assessed the control of landscape position and groundwater table dynamics on the spatiotemporal variability of soil respiration. We investigated growing season soil respiration in a ~393 ha subalpine watershed in Montana across eight riparian–hillslope transitions that differed in slope, upslope accumulated area (UAA), aspect, and groundwater table dynamics. We collected daily-to-weekly measurements of soil water content (SWC), soil temperature, soil …


An Interannual Assessment Of The Relationship Between The Stable Carbon Isotopic Composition Of Ecosystem Respiration And Climate In A High‐Elevation Subalpine Forest, Diego Andrés Riveros-Iregui, Jia Hu, Sean Burns, David R. Bowling, Russell K. Monson Jan 2011

An Interannual Assessment Of The Relationship Between The Stable Carbon Isotopic Composition Of Ecosystem Respiration And Climate In A High‐Elevation Subalpine Forest, Diego Andrés Riveros-Iregui, Jia Hu, Sean Burns, David R. Bowling, Russell K. Monson

School of Natural Resources: Faculty Publications

We measured the carbon isotopic composition (δ13C) of ecosystem respiration (δ13CR) in a subalpine forest across four growing seasons to examine whether patterns in δ13CR were consistent with those expected based on leaf‐level gas‐exchange theory, and in agreement with past studies of the relation between δ13CR and climate conducted across broad geographic regions. Conventional trends (i.e., less negative δ13CR with increased vapor pressure deficit (VPD) and air temperature (TAIR), and decreased soil moisture (θ)) were observed when we focused on the driest portions …


Integrating Info-Gap Decision Theory With Robust Population Management: A Case Study Using The Mountain Plover, Max Post Van Der Burg, Andrew J. Tyre Jan 2011

Integrating Info-Gap Decision Theory With Robust Population Management: A Case Study Using The Mountain Plover, Max Post Van Der Burg, Andrew J. Tyre

School of Natural Resources: Faculty Publications

Wildlife managers often make decisions under considerable uncertainty. In the most extreme case, a complete lack of data leads to uncertainty that is unquantifiable.Information-gap decision theory deals with assessing management decisions under extreme uncertainty, but it is not widely used in wildlife management. So too, robust population management methods were developed to deal with uncertainties in multiple-model parameters.However, the two methods have not, as yet, been used in tandem to assess population management decisions. We provide a novel combination of the robust population management approach for matrix models with the information-gap decision theory framework for making conservation decisions under extreme …


Confronting Socially Generated Uncertainty In Adaptive Management, Andrew J. Tyre, Sarah Michaels Jan 2011

Confronting Socially Generated Uncertainty In Adaptive Management, Andrew J. Tyre, Sarah Michaels

School of Natural Resources: Faculty Publications

As more and more organizations with responsibility for natural resource management adopt adaptive management as the rubric in which they wish to operate, it becomes increasingly important to consider the sources of uncertainty inherent in their endeavors. Without recognizing that uncertainty originates both in the natural world and in human undertakings, efforts to manage adaptively at the least will prove frustrating and at the worst will prove damaging to the very natural resources that are the management targets. There will be more surprises and those surprises potentially may prove at the very least unwanted and at the worst devastating. We …


Evaluating The Efficacy Of Adaptive Management Approaches: Is There A Formula For Success?, Jamie E. Mcfadden, Tim L. Hiller, Andrew J. Tyre Jan 2011

Evaluating The Efficacy Of Adaptive Management Approaches: Is There A Formula For Success?, Jamie E. Mcfadden, Tim L. Hiller, Andrew J. Tyre

School of Natural Resources: Faculty Publications

Within the field of natural-resources management, the application of adaptive management is appropriate for complex problems high in uncertainty. Adaptive management is becoming an increasingly popular management-decision tool within the scientific community and has developed into two primary schools of thought: the Resilience-Experimentalist School (with high emphasis on stakeholder involvement, resilience, and highly complex models) and the Decision-Theoretic School (which results in relatively simple models through emphasizing stakeholder involvement for identifying management objectives). Because of these differences, adaptive management plans implemented under each of these schools may yield varying levels of success. We evaluated peer-reviewed literature focused on incorporation of …


Review Of Mammalogy, 5th Edition By T. A. Vaughan, J. M. Ryan, And N. J. Czaplewski, Patricia W. Freeman Jan 2011

Review Of Mammalogy, 5th Edition By T. A. Vaughan, J. M. Ryan, And N. J. Czaplewski, Patricia W. Freeman

School of Natural Resources: Faculty Publications

Last summer I spent time with old friends. Terry Vaughan and company have significantly updated their text, Mammalogy, for the 5th edition (2011). The book is 62% larger than the 1st edition in 1972 (Vaughan 1972). Vaughan, Ryan, and Czaplewski skewer topics with a simplicity derived from years of mammalian research and teaching, and it is a pure pleasure to read. The synthetic nature of Mammalogy (2011) and exceptional clarity in writing make this edition an ideal book that is not just for class. Because much new research has been integrated into each chapter, all mammalogists will appreciate new …


Review Of Mammalian Teeth: Origin, Evolution, And Diversity By Peter S. Ungar, Patricia W. Freeman Jan 2011

Review Of Mammalian Teeth: Origin, Evolution, And Diversity By Peter S. Ungar, Patricia W. Freeman

School of Natural Resources: Faculty Publications

Peter Ungar has written a book on mammalian teeth, a topic close to the heart of mammalogy itself and most mammalogists. His distillation of the massive literature on teeth into a succinct whole will appeal to scientists and professionals across disciplines. With paleontological and extant dental research in one place I no longer have to search these areas separately to find what I want. Ungar’s broad background includes physical anthropology, anatomy, and paleontology. Further, he has been one of the pioneers using dental microwear to analyze diets in primates and geographic information systems (GISs) on a microscale to study cusps …


Estimating Daily Gross Primary Production Of Maize Based Only On Modis Wdrvi And Shortwave Radiation Data, Toshihiro Sakamoto, Anatoly Gitelson, Brian D. Wardlow, Shashi Verma, Andrew E. Suyker Jan 2011

Estimating Daily Gross Primary Production Of Maize Based Only On Modis Wdrvi And Shortwave Radiation Data, Toshihiro Sakamoto, Anatoly Gitelson, Brian D. Wardlow, Shashi Verma, Andrew E. Suyker

School of Natural Resources: Faculty Publications

Accurate assessment of temporal changes in gross primary production (GPP) is important for carbon budget assessments and evaluating the impact of climate change on crop productivity. The objective of this study was to devise a simple remote sensing- based GPP model to quantify daily GPP of maize. In the model, (1) daily shortwave radiation (SW), derived from the reanalysis data (North American Land Data Assimilation System; NLDAS-2) and (2) smoothed Wide Dynamic Range Vegetation Index (WDRVI) data, derived from Moderate Resolution Imaging Spectroradiometer (MODIS) 250-m observations were used as proxy variables of the incident photosynthetically active radiation (PAR) and the …


Seasonal Energy And Water Balance Of A Phragmites Australis-Dominated Wetland In The Republican River Basin Of South-Central Nebraska (Usa), John D. Lenters, Gregory J. Cutrell, Erkan Istanbulluoglu, Durelle T. Scott, Kyle S. Herrman, Dean E. Eisenhauer Jan 2011

Seasonal Energy And Water Balance Of A Phragmites Australis-Dominated Wetland In The Republican River Basin Of South-Central Nebraska (Usa), John D. Lenters, Gregory J. Cutrell, Erkan Istanbulluoglu, Durelle T. Scott, Kyle S. Herrman, Dean E. Eisenhauer

School of Natural Resources: Faculty Publications

energy and water balance, especially in dry climatic regions, can have a significant impact on local water availability and, therefore, water resource management. The purpose of this study is to quantify the energy and water balance of a riparian wetland in a subhumid region of the central US, as well as the role of seasonal climate variability and vegetation phenology. The site is located in the Republican River basin in south-central Nebraska, where decreases in streamflow have been observed in recent decades. In an effort to reduce consumptive water use from evapotranspiration (ET), and thereby reclaim surface water, invasive species …


Assessing Net Ecosystem Carbon Exchange Of U.S. Terrestrial Ecosystems By Integrating Eddy Covariance Flux Measurements And Satellite Observations, Jingfeng Xiao, Qianlai Zhuang, Beverly E. Law, Dennis D. Baldocchi, Jiquan Chen, Andrew D. Richardson, Jerry M. Melillo, Kenneth J. Davis, David Y. Hollinger, Sonia Wharton, Ram Oren, Asko Noormets, Marc L. Fischer, Shashi Verma, David R. Cook, Ge Sun, Steve Mcnulty, Steven C. Wofsy, Paul V. Bolstad, Sean P. Burns, Peter S. Curtis, Bert G. Drake, Matthias Falk, David R. Foster, Lianhong Gu, Julian L. Hadley, Gabriel G. Katul, Marcy Litvak, Siyan Ma, Timothy A. Martin, Roser Matamala, Tilden P. Meyers, Russell K. Monson, J. William Munger, Walter C. Oechel, U. Kyaw Tha Paw, Hans Peter Schmid, Russell L. Scott, Gregory Starr, Andrew E. Suyker, Margaret S. Torn Jan 2011

Assessing Net Ecosystem Carbon Exchange Of U.S. Terrestrial Ecosystems By Integrating Eddy Covariance Flux Measurements And Satellite Observations, Jingfeng Xiao, Qianlai Zhuang, Beverly E. Law, Dennis D. Baldocchi, Jiquan Chen, Andrew D. Richardson, Jerry M. Melillo, Kenneth J. Davis, David Y. Hollinger, Sonia Wharton, Ram Oren, Asko Noormets, Marc L. Fischer, Shashi Verma, David R. Cook, Ge Sun, Steve Mcnulty, Steven C. Wofsy, Paul V. Bolstad, Sean P. Burns, Peter S. Curtis, Bert G. Drake, Matthias Falk, David R. Foster, Lianhong Gu, Julian L. Hadley, Gabriel G. Katul, Marcy Litvak, Siyan Ma, Timothy A. Martin, Roser Matamala, Tilden P. Meyers, Russell K. Monson, J. William Munger, Walter C. Oechel, U. Kyaw Tha Paw, Hans Peter Schmid, Russell L. Scott, Gregory Starr, Andrew E. Suyker, Margaret S. Torn

School of Natural Resources: Faculty Publications

More accurate projections of future carbon dioxide concentrations in the atmosphere and associated climate change depend on improved scientific understanding of the terrestrial carbon cycle. Despite the consensus that U.S. terrestrial ecosystems provide a carbon sink, the size, distribution, and interannual variability of this sink remain uncertain. Here we report a terrestrial carbon sink in the conterminous U.S. at 0.63 pg C yr−1 with the majority of the sink in regions dominated by evergreen and deciduous forests and savannas. This estimate is based on our continuous estimates of net ecosystem carbon exchange (NEE) with high spatial (1 km) and …


Comparison And Analysis Of Empirical Equations For Soil Heat Flux For Different Cropping Systems And Irrigation Methods, Ayse Kilic, R. K. Singh, Elizabeth A. Walter-Shea, Shashi Verma, Andrew E. Suyker Jan 2011

Comparison And Analysis Of Empirical Equations For Soil Heat Flux For Different Cropping Systems And Irrigation Methods, Ayse Kilic, R. K. Singh, Elizabeth A. Walter-Shea, Shashi Verma, Andrew E. Suyker

School of Natural Resources: Faculty Publications

We evaluated the performance of four models for estimating soil heat flux density (G) in maize (Zea mays L.) and soybean (Glycine max L.) fields under different irrigation methods (center‐pivot irrigated fields at Mead, Nebraska, and subsurface drip irrigated field at Clay Center, Nebraska) and rainfed conditions at Mead. The model estimates were compared against measurements made during growing seasons of 2003, 2004, and 2005 at Mead and during 2005, 2006, and 2007 at Clay Center. We observed a strong relationship between the G and net radiation (Rn) ratio (G/Rn) and the normalized difference …


Farmer Perceptions Of Sustainable Agriculture Practices And Drought Risk Reduction In Nebraska, Usa, Cody L. Knutson, Tonya Haigh, Michael J. Hayes, Melissa Widhalm, J. Nothwehr, M. Kleinschmidt, L. Graf Jan 2011

Farmer Perceptions Of Sustainable Agriculture Practices And Drought Risk Reduction In Nebraska, Usa, Cody L. Knutson, Tonya Haigh, Michael J. Hayes, Melissa Widhalm, J. Nothwehr, M. Kleinschmidt, L. Graf

School of Natural Resources: Faculty Publications

Social factors, such as farming methods, have an impact on farm vulnerability to drought, but have received little research or policy attention. Some researchers and advocates have argued that sustainable agriculture systems are less vulnerable to climate risk than conventional systems because sustainable agriculture requires producers to have skills promoting adaptability. In this paper, we investigate producers’ perceptions on the use of sustainable agriculture in reducing drought risk, and what they believe would help them better adapt to drought. We surveyed and interviewed farmer members of two sustainable agriculture organizations in Nebraska, USA, during a multi-year drought period from 1999 …


Adaptive Harvest Management And Harvest Mortality Of Greater Prairie-Chickens, Larkin A. Powell, J. Scott Taylor, Ty W. Matthews Jan 2011

Adaptive Harvest Management And Harvest Mortality Of Greater Prairie-Chickens, Larkin A. Powell, J. Scott Taylor, Ty W. Matthews

School of Natural Resources: Faculty Publications

Adaptive harvest management (AHM) can assist biologists with decisions made under uncertainty. There have been few applications of AHM to manage wildlife at the state level, and we provide a theoretical exercise using AHM in the context of Greater Prairie-Chicken harvest in southeast Nebraska. Our goals were to develop and evaluate an AHM framework for a state specific harvest decision, and to use the AHM process to evaluate uncertainties associated with harvest mortality for Greater Prairie-Chickens in Nebraska. Harvest of prairie chickens in southeast Nebraska was restarted 2000, using a special limited permit system, and was controversial with respect to …