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Articles 1 - 16 of 16

Full-Text Articles in Physical Sciences and Mathematics

Local And Landscape Factors Affecting Nest Site Selection And Nest Success Of Burrowing Owls In Western Nebraska, Rebecca T. Ekstein Dec 1999

Local And Landscape Factors Affecting Nest Site Selection And Nest Success Of Burrowing Owls In Western Nebraska, Rebecca T. Ekstein

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

No abstract provided.


Ecology Of Elk In Northwestern Nebraska: Demographics, Effects Of Human Disturbance, And Characteristics Of Calving Habitat, Bruce A. Stillings Dec 1999

Ecology Of Elk In Northwestern Nebraska: Demographics, Effects Of Human Disturbance, And Characteristics Of Calving Habitat, Bruce A. Stillings

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

No abstract provided.


Earth In Four Dimensions: Development Of The Ideas Of Geologic Time And History, Robert F. Diffendal Jr. Oct 1999

Earth In Four Dimensions: Development Of The Ideas Of Geologic Time And History, Robert F. Diffendal Jr.

School of Natural Resources: Faculty Publications

Changes in ideas and in technology can come about as slow incremental modifications, as well as by major paradigm shifts. In the case of the development of the ideas of geologic history and time, I will try to present these changes broadly and then look at how some of these have affected interpretation of Nebraska geology. Changes of view on three fronts were important in the development of geologic history and time concepts. First is the question of the nature of time. Is time cyclic or is it linear? The Greco-Oriental cultures had a world view based on cosmic cycles, …


Soil Moisture Within The Windbreak/Crop Interface And A Comparison Of Three Types Of Sensors For Measuring Soil Water Content, Qingjiang Hou Aug 1999

Soil Moisture Within The Windbreak/Crop Interface And A Comparison Of Three Types Of Sensors For Measuring Soil Water Content, Qingjiang Hou

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

No abstract provided.


Central Platte River Forests: Breeding Birds And Woody Vegetation, Barbara K. Good Aug 1999

Central Platte River Forests: Breeding Birds And Woody Vegetation, Barbara K. Good

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

No abstract provided.


1999 Wildlife Management Area Threatened And Endangered Species Inventory, Final Report, Robert F. Steinauer Jan 1999

1999 Wildlife Management Area Threatened And Endangered Species Inventory, Final Report, Robert F. Steinauer

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

This study was undertaken to determine the extent of threatened and endangered (T&E) species habitats and high-quality native plant communities on Nebraska Game and Parks Commission (NGPC) Wildlife Management Areas (WMAs). The Nebraska Natural Heritage Program (NHP) is responsible for environmental reviews of state projects that may impact threatened and endangered (T&E) species in Nebraska, including proposed management actions on state Wildlife Management Areas (WMA). These environmental reviews require a significant amount of NHP staff time, and frequently find no adverse impacts associated with the proposed management actions. This survey was undertaken to improve Nebraska Game and Parks Commissions (NGPC) …


1999 Platte River Basin Ecosystem Symposium Proceedings Jan 1999

1999 Platte River Basin Ecosystem Symposium Proceedings

Water Current Newsletter

No abstract provided.


Notes And Correspondence: The Effects Of Data Gaps On The Calculated Monthly Mean Maximum And Minimum Temperatures In The Continental United States: A Spatial And Temporal Study, David E. Stooksbury, Craig D. Idso, Kenneth G. Hubbard Jan 1999

Notes And Correspondence: The Effects Of Data Gaps On The Calculated Monthly Mean Maximum And Minimum Temperatures In The Continental United States: A Spatial And Temporal Study, David E. Stooksbury, Craig D. Idso, Kenneth G. Hubbard

School of Natural Resources: Faculty Publications

Gaps in otherwise regularly scheduled observations are often referred to as missing data. This paper explores the spatial and temporal impacts that data gaps in the recorded daily maximum and minimum temperatures have on the calculated monthly mean maximum and minimum temperatures. For this analysis 138 climate stations from the United States Historical Climatology Network Daily Temperature and Precipitation Data set were selected. The selected stations had no missing maximum or minimum temperature values during the period 1951–80. The monthly mean maximum and minimum temperatures were calculated for each station for each month. For each month 1–10 consecutive days of …


Filter Strip Performance And Processes For Different Vegetation, Widths, And Contaminants, T. J. Schmitt, M. G. Dosskey, K. D. Hoagland Jan 1999

Filter Strip Performance And Processes For Different Vegetation, Widths, And Contaminants, T. J. Schmitt, M. G. Dosskey, K. D. Hoagland

School of Natural Resources: Faculty Publications

Filter strips are widely prescribed to reduce contaminants in surface runoff from agricultural fields. Tbis study compared performance of different filter strip designs on several contaminants and evaluated the contribnting processes. Different vegetation types and widths were investigated using simulated runoff event on large plots (3 m X 7.5 or 15 m) having fine-textured soil and a 6 to 7% slope. Filter strips 7.5 and 15 m wide downslope greatly reduced concentrations of sediment in runoff (76-93%) and contaminants strongly associated with sediment (total P, 55-79%; permethrin, 27-83% [(3-phenoxyphenyl) methyl (±)-cis, trans-3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane carboxylate ]). They had less effect on concentrations …


An Objective Method For Determining Principal Time Scales Of Coherent Eddy Structures Using Orthonormal Wavelets, Jozsef Szilagyi, Marc B. Parlange, Gabriel G. Katul, John D. Albertson Jan 1999

An Objective Method For Determining Principal Time Scales Of Coherent Eddy Structures Using Orthonormal Wavelets, Jozsef Szilagyi, Marc B. Parlange, Gabriel G. Katul, John D. Albertson

School of Natural Resources: Faculty Publications

No abstract provided.


Streamflow Depletion Investigations In The Republican River Basin: Colorado, Nebraska, And Kansas, Jozsef Szilagyi Jan 1999

Streamflow Depletion Investigations In The Republican River Basin: Colorado, Nebraska, And Kansas, Jozsef Szilagyi

School of Natural Resources: Faculty Publications

No abstract provided.


A Revised Measurement Methodology For Conifer Needles Spectral Optical Properties: Evaluating The Influence Of Gaps Between Elements, Mark A. Mesarch, Elizabeth Walter-Shea, Gregory P. Asner, Elizabeth M. Middleton, Stephen Chan Jan 1999

A Revised Measurement Methodology For Conifer Needles Spectral Optical Properties: Evaluating The Influence Of Gaps Between Elements, Mark A. Mesarch, Elizabeth Walter-Shea, Gregory P. Asner, Elizabeth M. Middleton, Stephen Chan

School of Natural Resources: Faculty Publications

Gaps are unavoidable when compositing small or narrow plant parts (e.g., conifer needles, twigs, narrow leaves, and leaflets) on sample holders in preparation for measuring spectral optical properties. The Daughtry et al. (1989) (A new technique to measure the spectral properties of conifer needles. Remote Sens. Environ. 27:81-91.) method of measuring conifer needle optical properties utilizes a relatively large gap fraction (approximately 0.3-0.6) and needles painted black on one surface of the sample from which the gap fraction of the sample is indirectly determined. Following this protocol typically results in distortions in optical properties, including underestimates in transmittance (sometimes negative …


The Relative Importance Of Patch Area And Perimeter–Area Ratio To Grassland Breeding Birds, Christopher J. Helzer, Dennis E. Jelinski Jan 1999

The Relative Importance Of Patch Area And Perimeter–Area Ratio To Grassland Breeding Birds, Christopher J. Helzer, Dennis E. Jelinski

School of Natural Resources: Faculty Publications

Habitat fragmentation has been implicated as a major cause of population decline in grassland birds. We tested the hypothesis that a combination of area and shape determines the use of grassland patches by breeding birds. We compared both species richness and individual species presence in 45 wet meadow grasslands in the floodplain of the central Platte River, Nebraska. Bird data were collected through the use of belt transects and supplemented by walking and listening outside transects. Our data supported our primary hypothesis that perimeter–area ratio, which reflects both the area and shape of a patch, is the strongest predictor of …


Inventory Of The Central Mixed-Grass Prairie Ecoregion Of Kansas And Nebraska, Hillary Loring, Mike Bullerman, Kelly Kindscher Jan 1999

Inventory Of The Central Mixed-Grass Prairie Ecoregion Of Kansas And Nebraska, Hillary Loring, Mike Bullerman, Kelly Kindscher

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

An inventory of potential high quality mixed-grass prairie ranches and large properties within the Central Mixed-Grass Prairie Ecoregion of Kansas and Nebraska was conducted in the spring and summer of 1999. Emphasis during the inventory was placed on identification of relatively intact landscapes. Significant ranches within those untilled landscapes were visited. An interview of the owners or managers of those properties was coupled with a survey of the vegetation. Assessments of quality were based on species composition, continuity of ground cover, observations of livestock impact, and viability of the community types present.

The objectives of this study were to:

1) …


1999 Nebraska Central Mixedgrass Prairie Rapid Ecological Assessment, Mike Bullerman Jan 1999

1999 Nebraska Central Mixedgrass Prairie Rapid Ecological Assessment, Mike Bullerman

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

This document has been prepared in partial fulfillment of the 1999 Central Mixedgrass Prairie ecoregion [CMGP] Rapid Ecological Assessment [REA] contract between the Nebraska Chapter of The Nature Conservancy [TNC] and Michael J. Bullerman [“contractor”]. The contract provided for the survey of selected untilled landscapes within the Nebraska portion of the CMGP ecoregion, excluding the Sandhills. The objectives of this study were to:

1) Identify relatively intact CMGP landscapes within the state of Nebraska,

2) Determine the ecological condition, threats, unique features, and conservation potential of these landscapes,

3) Determine land use practices implemented by landowners,

4) Determine landowner attitudes …


Characterization And Improvement Of Eos Land Products Using Measurements At Ameriflux Grassland And Wheat Sites In The Arm/Cart Region: Research Annual Performance Report For Period March 1, 1999- February 29, 2000., E. A. Walter-Shea, S. B. Verma Jan 1999

Characterization And Improvement Of Eos Land Products Using Measurements At Ameriflux Grassland And Wheat Sites In The Arm/Cart Region: Research Annual Performance Report For Period March 1, 1999- February 29, 2000., E. A. Walter-Shea, S. B. Verma

School of Natural Resources: Documents and Reviews

No abstract provided.