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Articles 1 - 13 of 13

Full-Text Articles in Physical Sciences and Mathematics

Analysis Of Integrated Farming Systems In Eastern Nebraska, Lori A. Hoagland Dec 2002

Analysis Of Integrated Farming Systems In Eastern Nebraska, Lori A. Hoagland

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

Agroecosystems in the U.S. are beset with social, ecological and environmental problems as large industrial farming methods are edging out small family-sized farms and replacing ecological services provided by biodiversity with synthetic inputs and practices. While many of the benefits of smaller diversified or integrated farming systems are well known, farm producers need a concrete model that shows how integration is possible and with what crops. The objective of this study was to investigate some of these supplemental farm activities, and identify and evaluate whether they were compatible given the time and resource constraints of a typical eastern Nebraska farm. …


The Role Of Climate In Modern Water Planning And Related Decisions: Nebraska Case Study, Donna L. Woudenberg Dec 2002

The Role Of Climate In Modern Water Planning And Related Decisions: Nebraska Case Study, Donna L. Woudenberg

Open Access Master's Theses (through 2010)

Climate and weather play an integral role in the planning and decision-making processes for those involved in agricultural and natural resource fields. This project was conducted to determine whether climate and weather data are being efficiently and effectively used in these processes.

A survey was mailed to those who work in water-related fields in Nebraska and post-survey interviews were conducted to obtain greater detail. Survey results were analyzed in the following three ways: as a whole; stratified by respondent’s agency; and stratified by the educational background of respondents. It was found that climate and weather data are more likely to …


A Regional Gis-Based Analysis Of Elk Habitat Suitability In Northwestern Nebraska, Justin W. Fischer Aug 2002

A Regional Gis-Based Analysis Of Elk Habitat Suitability In Northwestern Nebraska, Justin W. Fischer

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

The need to accurately assess the use and suitability of elk (Cervus elaphus spp.) habitat at regional scales will continue to increase as human development encroaches into what was once optimum elk habitat. The objectives of this research were to calculate the relative proportions of habitat use by elk in the Pine Ridge region of Northwestern Nebraska from a set of radio-collared elk locations and generate a habitat suitability model. Habitat variables (Iandcover type, aspect, slope, distance to a road, road density, and distance from the ponderosa pine edge) were measured for each elk location (n = 5,787 dating …


A Regional Gis-Based Analysis Of Elk Habitat Suitability In Northeast Nebraska, J W. Fisher Aug 2002

A Regional Gis-Based Analysis Of Elk Habitat Suitability In Northeast Nebraska, J W. Fisher

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

No abstract provided.


Effectiveness Of Frightening Devices For Reducing Deer Damage In Cornfields, Jason M. Gilsdorf Aug 2002

Effectiveness Of Frightening Devices For Reducing Deer Damage In Cornfields, Jason M. Gilsdorf

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

No abstract provided.


Influence Of Light And Nutrients On Atrazine Toxicity To Freshwater Algae, Crystal J. Hansen Aug 2002

Influence Of Light And Nutrients On Atrazine Toxicity To Freshwater Algae, Crystal J. Hansen

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

No abstract provided.


Impact Of Irrigation On Midsummer Surface Fluxes And Temperature Under Dry Synoptic Conditions: A Regional Atmospheric Model Study Of The U.S. High Plains, Jimmy O. Adegoke, Roger A. Pielke Sr., J. Eastman, Rezaul Mahmood, Kenneth G. Hubbard Jul 2002

Impact Of Irrigation On Midsummer Surface Fluxes And Temperature Under Dry Synoptic Conditions: A Regional Atmospheric Model Study Of The U.S. High Plains, Jimmy O. Adegoke, Roger A. Pielke Sr., J. Eastman, Rezaul Mahmood, Kenneth G. Hubbard

School of Natural Resources: Faculty Publications

The impact of irrigation on the surface energy budget in the U.S. high plains is investigated. Four 15-day simulations were conducted: one using a 1997 satellite-derived estimate of farmland acreage under irrigation in Nebraska (control run), two using the Olson Global Ecosystem (OGE) vegetation dataset (OGE wet run and OGE dry run), and the fourth with the Kuchler vegetation dataset (natural vegetation run) as lower boundary conditions in the Colorado State University Regional Atmospheric Modeling System (RAMS). In the control and OGE wet simulations, the topsoil in the irrigated locations, up to a depth of 0.2 m, was saturated at …


Anthropogenic Land-Use Change In The North American Tall Grass-Short Grass Transition And Modification Of Near-Surface Hydrologic Cycle, Rezaul Mamood, Kenneth Hubbard May 2002

Anthropogenic Land-Use Change In The North American Tall Grass-Short Grass Transition And Modification Of Near-Surface Hydrologic Cycle, Rezaul Mamood, Kenneth Hubbard

School of Natural Resources: Faculty Publications

During the 19th and 20th centuries, the landscape of the North American Great Plains was rapidly modified from natural grasslands to agricultural farmlands. These changes affected much of the continent with potential impacts in grasslands equal to deforestation elsewhere. Therefore, the resulting impacts on weather and climate should be studied. In this study, a soil water balance model is applied for 3 land uses at 3 locations. These locations are representative of the east to west declining precipitation gradient of the Great Plains. It was found, in McCook, Nebraska, for example, that annual total evapotranspiration for irrigated maize is 36% …


Rapid Ecological Assessment Of The Northern Mixedgrass Prairie Ecoregion (Nebraska Portion), Gerry Steinauer Jan 2002

Rapid Ecological Assessment Of The Northern Mixedgrass Prairie Ecoregion (Nebraska Portion), Gerry Steinauer

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

This study was conducted as part of The Nature Conservancy’s (TNC) project to conduct ecoregional conservation planning throughout the continental United States. TNC contracted with the Nebraska Game and Parks Commission (NGPC) to conduct a rapid ecological assessment (REA) of the portion of the Northern Mixedgrass Prairie ecoregion (NMGP) occurring in Nebraska. This report concludes that agreement. Roughly the northern 1/5 of central Nebraska occurs within the NMGP (Figure 1). This ecoregion also includes extensive area of central South Dakota and central North Dakota. The objective of this study was to conduct a REA of the untilled landscapes within the …


Macrohabitat Composition Surrounding Successful And Depredated Northern Bobwhite Nests, Eric L. Staller, William E. Palmer, John P. Carroll Jan 2002

Macrohabitat Composition Surrounding Successful And Depredated Northern Bobwhite Nests, Eric L. Staller, William E. Palmer, John P. Carroll

School of Natural Resources: Faculty Publications

Relationships among macrohabitat and depredation of northern bobwhite (Colinus virginianus) nests are poorly understood. Yet, macrohabitat composition may influence the nest predator community and, therefore, the vulnerability of northern bobwhite nests to depredation. We determined if macrohabitat composition surrounding bobwhite nests influenced nest placement, nest success, and which predators were responsible for depredating nests. We characterized macrohabitats at 2 scales, 8 and 16 ha, by surrounding both bobwhite nests, and an equal number of random locations, with a circular buffer. Random points were placed within the area used by bobwhites on our study area. We then determined the …


Wood Thrush Movements And Habitat Use: Effects Of Forest Management For Red-Cockaded Woodpeckers, Jason Lang, Larkin A. Powell, David Krementz, Michael J. Conroy Jan 2002

Wood Thrush Movements And Habitat Use: Effects Of Forest Management For Red-Cockaded Woodpeckers, Jason Lang, Larkin A. Powell, David Krementz, Michael J. Conroy

School of Natural Resources: Faculty Publications

We monitored adult and juvenile breeding-season movements and habitat use of radio-tagged Wood Thrushes (Hylocichla mustelina) at the Piedmont National Wildlife Refuge, central Georgia, USA. We investigated the effects that management for Red-cockaded Woodpeckers (Picoides borealis), thinning and burning >30 year old loblolly pine (Pinus taeda) habitat, had on Wood Thrushes, a ground-foraging and midstory-nesting species. Adult Wood Thrush pairs regularly moved long distances between nesting attempts (range 1 to 17,388 m). The only experimental effect we found on adult movements was a decrease in weekly emigration rates (AP) from thinned and burned compartments …


Realtime Data Filtering Models For Air Temperature Measurements, Kenneth G. Hubbard, X. Lin Jan 2002

Realtime Data Filtering Models For Air Temperature Measurements, Kenneth G. Hubbard, X. Lin

School of Natural Resources: Faculty Publications

Air temperature measurement biases caused by solar radiation and ambient wind speed are well-known. However, realtime air temperature filtering models are essential for generating homogeneous climate data by transforming one air temperature measurement system into another, and correcting in-situ air temperature biases especially for non-aspirated radiation shield systems. This study investigated the air temperature biases caused in the commonly used radiation shields in the United States, including the ASOS, MMTS, Gill, CRS, ASP-ES, and NON-ASPES shields along with corresponding temperature sensors. The realtime air temperature filtering models developed for each air temperature system are capable of removing the solar radiation …


Land Use Change And Modification Of Near-Surface Thermal Records In The Northern Great Plains, Rezaul Mahmood, Ken Hubbard, Christy Carlson Jan 2002

Land Use Change And Modification Of Near-Surface Thermal Records In The Northern Great Plains, Rezaul Mahmood, Ken Hubbard, Christy Carlson

HPRCC Personnel Publications

The North American Great Plains have experienced a rapid overturning of natural grasslands to agricultural land use over the last century. Moreover, in some areas more than 80% of the land use has changed from dry land to irrigated agriculture during the second half of the twentieth century. It is speculated that these changes have modified near-surface atmospheric condition and our modeling study seems to support this. To identify changes in land surface- atmospheric modifications we have applied a soil moistureenergy balance model at three locations in Nebraska: Mead, York, and McCook. The model was applied for three land uses …