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Articles 1 - 12 of 12

Full-Text Articles in Physical Sciences and Mathematics

Crop Yield Gaps: Their Importance, Magnitudes, And Causes, David B. Lobell, Kenneth G. Cassman, Christopher B. Field Oct 2009

Crop Yield Gaps: Their Importance, Magnitudes, And Causes, David B. Lobell, Kenneth G. Cassman, Christopher B. Field

Nebraska Center for Energy Sciences Research: Publications

Future trajectories of food prices, food security, and cropland expansion are closely linked to future average crop yields in the major agricultural regions of the world. Because the maximum possible yields achieved in farmers’ fields might level off or even decline in many regions over the next few decades, reducing the gap between average and potential yields is critical. In most major irrigated wheat, rice, and maize systems, yields appear to be at or near 80% of yield potential, with no evidence for yields having exceeded this threshold to date. A fundamental constraint in these systems appears to be uncertainty …


Applications And Potentials For Biogenic Methane Recovery Operations In Nebraska Agriculture, Industry, And Economic Development, David Micheal Dingman Jul 2009

Applications And Potentials For Biogenic Methane Recovery Operations In Nebraska Agriculture, Industry, And Economic Development, David Micheal Dingman

Department of Environmental Studies: Undergraduate Student Theses

ABSTRACT: This thesis report illustrates the applications and potentials of biogenic methane recovery in Nebraska’s agricultural and industrial sectors and as a means for increasing sustainable economic development in the state’s rural communities. As the nation moves toward a new green economy, biogenic methane recovery as a waste management strategy and renewable energy resource presents significant opportunities for Nebraska to be a national and world leader in agricultural and industrial innovation, advanced research and development of renewable energy technology, and generation of new product markets. Nebraska’s agricultural economy provides a distinct advantage to the state for supporting methane recovery operations …


Slides: Indian Water Rights, Robert T. Anderson Jun 2009

Slides: Indian Water Rights, Robert T. Anderson

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: Robert T. Anderson, Native American Law Center, University of Washington Law School

19 slides


Slides: Status Of Southern Nevada Water Authority (Snwa): Third Intake Into Lake Mead And Groundwater Project, Kay Brothers Jun 2009

Slides: Status Of Southern Nevada Water Authority (Snwa): Third Intake Into Lake Mead And Groundwater Project, Kay Brothers

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: Kay Brothers, Southern Nevada Water Authority (SNWA), Las Vegas, NV

37 slides


Slides: Northern Integrated Supply Project, Northern Front Range--Colorado, Don Carlson Jun 2009

Slides: Northern Integrated Supply Project, Northern Front Range--Colorado, Don Carlson

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: Don Carlson, Northern Colorado Water Conservancy District

20 slides


Slides: Water Leasing In The Lower Arkansas Valley: The "Super Ditch Company", Peter Nichols Jun 2009

Slides: Water Leasing In The Lower Arkansas Valley: The "Super Ditch Company", Peter Nichols

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: Peter NIchols, Trout, Raley, Montano, Witwer & Freeman, Denver, CO

28 slides


Slides: Finding Flows: Fish Still Need Water Everyday, Melinda Kassen Jun 2009

Slides: Finding Flows: Fish Still Need Water Everyday, Melinda Kassen

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: Melinda Kassen, Director of the Western Water Project, Trout Unlimited

12 slides


Slides: Agricultural Resilience And Urban Growth: A Closer Look, William R. Travis Jun 2009

Slides: Agricultural Resilience And Urban Growth: A Closer Look, William R. Travis

Western Water Law, Policy and Management: Ripples, Currents, and New Channels for Inquiry (Martz Summer Conference, June 3-5)

Presenter: William R. Travis, Department of Geography, Center for Science & Technology Policy Research, CIRES, University of Colorado at Boulder

30 slides


Soil Organic Carbon And Site Characteristics In Aspen And Evaluation Of The Potential Effects Of Conifer Encroachment On Soil Properties In Northern Utah, Mical K. Woldeselassie May 2009

Soil Organic Carbon And Site Characteristics In Aspen And Evaluation Of The Potential Effects Of Conifer Encroachment On Soil Properties In Northern Utah, Mical K. Woldeselassie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In the Intermountain West, aspen (Populus tremuloides) has declined mainly due to a combination of successional processes, fire suppression and long-term use of ungulates which has led to replacement by conifers, sagebrush or other shrub communities. Conifer encroachment is believed to cause critical changes in the ecosystem properties. In order to understand the impacts of conifer encroachment on soil properties such as soil organic carbon (SOC) storage, soil morphology, and soil chemical properties, and the implications of such changes, it is very important to assess the soil properties under the two vegetation types. The objectives of this study …


Historical Review Of Elk–Agriculture Conflicts In And Around Riding Mountain National Park, Manitoba, Canada, Ryan K. Brook Apr 2009

Historical Review Of Elk–Agriculture Conflicts In And Around Riding Mountain National Park, Manitoba, Canada, Ryan K. Brook

Human–Wildlife Interactions

Conflicts between elk (Cervus elaphus) and farmers have been occurring since the 1880s when agriculture began around what is now Riding Mountain National Park (RMNP). Initially, the conflicts were related to low elk numbers caused primarily by unregulated harvest of elk. The creation of RMNP in 1930 and the associated ban on hunting allowed elk numbers to reach critically high levels. Since farming began, elk have been associated with considerable damage to fences and crops around RMNP, with annual damage often >$240,000. Hunting on agricultural lands has been the most common approach to mitigating elk impacts, despite its limited success. …


Changes In Producer Attitudes Towards Windbreaks In Eastern Nebraska, 1983 To 2009, Kim Tomczak Apr 2009

Changes In Producer Attitudes Towards Windbreaks In Eastern Nebraska, 1983 To 2009, Kim Tomczak

Department of Environmental Studies: Undergraduate Student Theses

Abstract Windbreaks are rows of trees or shrubs arranged on the landscape to reduce wind speed. In agricultural landscapes we find them as farmstead windbreaks, livestock windbreaks and field windbreaks. While farmstead and livestock windbreaks are well accepted by the agricultural community, field windbreaks are often viewed differently. A 1982 study of the attitudes of farmers in Eastern Nebraska indicated that many of the producers were around the age of 50 and that they used different types of windbreaks. This study repeated that survey in the same. When compared to data from 1982, farmers today are not educated about the …


Long-Term Agricultural Land-Use Trends In Nebraska, 1866–2007, Tim L. Hiller, Larkin A. Powell, Tim D. Mccoy, Jeffrey J. Lusk Jan 2009

Long-Term Agricultural Land-Use Trends In Nebraska, 1866–2007, Tim L. Hiller, Larkin A. Powell, Tim D. Mccoy, Jeffrey J. Lusk

School of Natural Resources: Faculty Publications

Although landscape changes from anthropogenic causes occur at much faster rates than those from natural processes (e.g., geological, vegetation succession), human perception of such changes is often subjective, inaccurate, or nonexistent. Given the large-scale land-use changes that have occurred throughout the Great Plains, the potential impacts of land-use changes on ecological systems, and the insight gained from knowledge of land-use trends (e.g., to compare to wildlife population trends), we synthesized information related to land-use trends in Nebraska during 1866–2007. We discussed and interpreted known and potential causes of short- and long-term land-use trends based on agricultural and weather data; farm …