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Full-Text Articles in Physical Sciences and Mathematics

Reconnaissance Survey Of Lewis And Clark On The Missouri National Recreational River, Nebraska And South Dakota, Anne P. Diffendal, Gary E. Moulton, Michael Shambaugh-Miller, Robert F. Diffendal Dec 1999

Reconnaissance Survey Of Lewis And Clark On The Missouri National Recreational River, Nebraska And South Dakota, Anne P. Diffendal, Gary E. Moulton, Michael Shambaugh-Miller, Robert F. Diffendal

Papers in Natural Resources

Table of Contents
Acknowledgments
Table of Contents
Figures
Part I
"Lewis and Clark on the Middle Missouri" by Gary E. Moulton
Appendix: Principal Sites and Events
Select Bibliography
Part II
Locating Lewis and Clark Sites
Site #1 Floyd's Bluff
Site #2 Gass's Election
Site #3 Ionia Volcano
Site #4 1804 Mouth of the Vermillion River
Site #5 Spirit Mound
Site #6 Shannon's Absence
Site #7 Calumet Bluff
Site #8 "Ancient Fortifications"
Site #9 Mouth of the Niobrara River
Site # 10 Old Baldy


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.

Papers in Natural Resources

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, …


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

Papers in Natural Resources

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

Papers in Natural Resources

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 …


Iron-Mediated Remediation Of Rdx-Contaminated Water And Soil Under Controlled Eh/Ph, J. Singh, Steven Comfort, Patrick Shea Jan 1999

Iron-Mediated Remediation Of Rdx-Contaminated Water And Soil Under Controlled Eh/Ph, J. Singh, Steven Comfort, Patrick Shea

Papers in Natural Resources

Soil and water contaminated with hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a serious environmental problem at several active and abandoned munitions production facilities. Zero-valent iron (Fe0) can effectively remediate RDX-contaminated soil and water. The objective of this study was to manipulate Eh and pH for enhanced Fe0-mediated destruction of RDX. This was accomplished by monitoring RDX destruction under controlled Eh-pH conditions (Eh: −300 to +150 mV; pH: 2−10). Decreasing Eh and pH increased RDX destruction in aqueous solution. Treating 20 mg of RDX L-1 (90 μM) under a static Eh of −150 mV and pH 7 with 20 g …


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

Papers in Natural Resources

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 …


Satellite-Based Adjustments For The Urban Heat Island Temperature Bias, Kevin P. Gallo, Timothy W. Owen Jan 1999

Satellite-Based Adjustments For The Urban Heat Island Temperature Bias, Kevin P. Gallo, Timothy W. Owen

Papers in Natural Resources

Monthly and seasonal relationships between urban–rural differences in minimum, maximum, and average temperatures measured at surface-based observation stations were compared to satellite-derived Advanced Very High Resolution Radiometer estimates of a normalized difference vegetation index (NDVI) and surface radiant temperature.


Temperature Trends Of The U.S. Historical Climatology Network Based On Satellite-Designated Land Use/Land Cover, Kevin P. Gallo, Timothy W. Owen, David R. Easterling, Paul F. Jamason Jan 1999

Temperature Trends Of The U.S. Historical Climatology Network Based On Satellite-Designated Land Use/Land Cover, Kevin P. Gallo, Timothy W. Owen, David R. Easterling, Paul F. Jamason

Papers in Natural Resources

The 1221 weather observation stations that compose the U.S. Historical Climatology Network were designated as either urban, suburban, or rural based on data from the Defense Meteorological Satellite Program Operational Linescan System (OLS).


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

Papers in Natural Resources

No abstract provided.


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

Papers in Natural Resources

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 …


Global Rural Temperature Trends, Thomas C. Peterson, Kevin P. Gallo, Jay Lawrimore, Timothy W. Owen, Alex Huang, David A. Mckittrick Jan 1999

Global Rural Temperature Trends, Thomas C. Peterson, Kevin P. Gallo, Jay Lawrimore, Timothy W. Owen, Alex Huang, David A. Mckittrick

Papers in Natural Resources

Using rural/urban land surface classifications derived from maps and satellite observed nighttime surface lights, global mean land surface air temperature time series were created using data from all weather observing stations in a global temperature data base and from rural stations only. The global rural temperature time series and trends are very similar to those derived from the full data set. Therefore, the well-known global temperature time series from in situ stations is not significantly impacted by urban warming.


Geology Of Rock Creek Station State Historical Park, Robert F. Diffendal Jan 1999

Geology Of Rock Creek Station State Historical Park, Robert F. Diffendal

Papers in Natural Resources

Contents:
Acknowledgments
Location and Facilities
Geology of the Park
Valley Floor of Rock Creek
While You Are in the Area


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

Papers in Natural Resources

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 …