Physical Sciences and Mathematics Commons^™

Converted Railroad Corridors As Avian Habitat In Southeast Nebraska, Kevin L. Poague

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

No abstract provided.

Climatic Impact Of The A.D. 1783 Asama (Japan) Eruption Was Minimal: Evidence From The Gisp2 Ice Core, G. A. Zielinski, R. J. Fiacco, Paul Andrew Mayewski, L. D. Meeker, S. Whitlow, M. S. Twickler, M. S. Germani, K. Endo, M. Yasui

Earth Science Faculty Scholarship

Assessing the climatic impact of the A.D. 1783 eruption of Mt. Asama, Japan, is complicated by the concurrent eruption of Laki, Iceland. Estimates of the stratospheric loading of H₂SO₄ for the A.D. 1108 eruption of Asama derived from the SO₄²⁻ time series in the GISP2 Greenland ice core indicate a loading of about 10.4 Tg H₂SO₄ with a resulting stratospheric optical depth of 0.087. Assuming sulfur emissions from the 1783 eruption were only one‐third of the 1108 event yields a H₂SO₄ loading value of 3.5 Tg and a stratospheric …

Groundwater Flow And Elastoplastic Stress-Strain Model For Cohesive Soils With Application To Channel Bank Stability, Richard A. Rohlf, Billy J. Barfield, Gary K. Felton

KWRRI Research Reports

A saturated-unsaturated groundwater flow and elastoplastic stress-strain finite element model was developed for simulating the mechanical behavior of rill and gully sized channel banks. The model coupled the two-dimensional saturated-unsaturated groundwater flow equation with a plane strain formulation of the virtual work equation. The constitutive relationship used the modified Cam clay yield function. The model included the effects of seepage force and variation in soil cohesive strength due to changes in water content and void ratio. A staggered solution procedure was used in which the groundwater equation was solved first to determine seepage force and soil cohesive force, and then …

Hydrogeological And Hydrochemical Characterization Of The Matozinhos-Pedro Leopoldo Karst, Brazil, Augusto Auler

Masters Theses & Specialist Projects

The Matozinhos-Pedro Leopoldo limestone area is a tropical karst located near the metropolis of Belo Horizonte, East Central Brazil, in an area undergoing rapid urbanization and land degradation. Qualitative dye tracing experiments have determined the groundwater routes and catchment areas in the two major drainage basins in the area, Samambaia Basin and Palmeiras-Mocambo Basin. Other drainage basins were identified, but not traced due to the absence of related swallets. Fluorescein and optical brightener had a poor performance as tracers under tropical climate. Dilution due to the existance of lakes at some swallets prevented some dye traces. The water that flows …

Phosphorus Immobilization In Poultry Litter And Litter-Amended Soils With Aluminum, Calcium And Iron Amendments, D. M. Miller, P. A. Moore Jr., T. C. Daniels

Technical Reports

Arkansas produces approximately one billion broilers each year. Phosphorous (P) runoff from fields receiving poultry litter is believed to be one of the primary factors affecting water quality in Northwest Arkansas. Poultry litter contains approximately 20 g P kg-1, of which about 2 g P kg-1 is water soluble. Soils that have received repeated heavy applications of litter may have water soluble P contents of as high as 10 mg P Kg-1 soil. The objective of this study was to determine if soluble P levels could be reduced in poultry litter and litter-amended soils with Al,Ca, and/or Fe amendments. Poultry …

Temporal Alternation Between Light- And Nutrient-Limitation Of Phytoplankton Production In A Coastal Plain Estuary., Jonathan Pennock, Jonathan H. Sharp

School of Marine Science and Ocean Engineering

ABSTRACT: The potential for Light- and nutrient-limitation of phytoplankton production was examined in the Delaware Estuary, USA, by combining a hierarchy of expenmental approaches including smallscale bioassay experiments, ecosystem-level analysis of nutrient concentration and stoichiometric ratios, and light-limitation modeling. Light was found to be the predominate regulator of phytoplankton growth throughout the estuary during the winter period as a result of high turbidity and a wellmixed water column. However, during late spring, phosphorus (P) was found to limit growth. This observation was confirmed at each of the experimental levels, and was related to several factors, including elevated input ratios (230:l) …

Agenda: Water Organizations In A Changing West, University Of Colorado Boulder. Natural Resources Law Center

Water Organizations in a Changing West (Summer Conference, June 14-16)

Conference organizers, faculty and/or moderators included University of Colorado School of Law professors Lawrence J. MacDonnell, David H. Getches and James N. Corbridge, Jr.

Water organizations in the western United States range from small, traditional acequia associations to large metropolitan water suppliers. What do these vastly different kinds of organizations have in common? All are feeling the pressures of change in the region--growing urban populations, environmental concerns, and calls for public participation.

This year's summer program will examine how water organizations are adapting to these pressures for change. Speakers drawn from urban, agricultural, and community organizations will share their experiences …

Assessment Of Effectiveness Of Buffer Zones In Removing Impurites In Runoff From Areas Treated With Poultry Litter, I. Chaubey, D. R. Edwards, T. C. Daniels

Technical Reports

Land application of animal manures (e.g. poultry litter, poultry manure, and swine manure) to pasture and range can lead to runoff quality degradation during storms that occur soon after application. Vegetative filter strips (VFS) have been shown to reduce pollution in runoff from row-cropped areas but have not been extensively studied in pasture and range settings. This research involved characterizing performance of fescue VFS in improving quality of runoff from pasture land areas treated with poultry litter and swine manure. The VFS were found to be quite effective in reducing off-site transport of ammonia nitrogen (NH3-N), total Kjeldahl nitrogen (TKN), …

Correlating Soil Test Phosphorus Losses In Runoff, D. H. Pote, T. C. Daniel, P. A. Moore Jr., D. J. Nichols, D. R. Edwards, A. N. Sharpley

Technical Reports

Phosphorus in agricultural runoff is often a major cause of accelerated eutrophication of lakes and streams. Previous research has indicated that the amount of dissolved P (DP) in runoff is directly related to P content of the surface soil. Decades of fertilizer application at rates exceeding those of crop uptake have elevated soil test P (STP) levels in areas of intensive crop and livestock production, making this the major source of DP loss in runoff. The objective of our experiment was to relate STP content of Captina silt loam to P concentration and loss in runoff, and determine which STP …

Banded Agates, Origins And Inclusions, Roger K. Pabian, Andrejs Zarins

Conservation and Survey Division

No abstract provided.

The Prediction Of Sediment And Nutrient Transport In The Buffalo River Watershed Using A Geographic Information System, H. D. Scott, P. A. Smith

Technical Reports

The Buffalo River was established by Congress in 1972 as the first National River in the United States. It is one of the few remaining free-flowing streams in northern Arkansas. The river originates in the higher elevations of the Boston Mountains in Newton County, and generally flows northeastward, intersecting the Springfield and Salem Plateaus as it drops from approximately 2000 feet in the headwaters to around 500 feet at the confluence with the White River in Marion County. It is considered by many to be one of Arkansas' greatest natural treasures, and therefore , there is strong interest in protecting …

Record Drilling Depth Struck In Greenland, Paul Andrew Mayewski, M. S. Twickler, J. E. Dibb, M. Wumkes, J. Klinck, J. S. Putscher, K. C. Taylor, D. A. Meese, E. D. Waddington, R. B. Alley, P. M. Grootes, M. Ram, M. Wahlen, A. T. Wilson

Earth Science Faculty Scholarship

On July 1, 1993, after 5 years of drilling, the Greenland Ice Sheet Project (GISP2) penetrated several meters of silty ice and reached bedrock at a depth of 3053.4 m. It then penetrated 1.5 m into the bedrock, producing the deepest ice core ever recovered (Figure 1).

In July 1992, a nearby European ice coring effort, the Greenland Ice Core Project (GRIP), reached an ice depth of 3028.8 m, providing more than 250,000 years of record. Comparisons between these ice core records have already demonstrated the remarkable reproducibility of the upper ∼90% of the records unparalleled view of climatic and …

Fundamentals Of Groundwater Contamination, Darryll T. Pederson

Conservation and Survey Division

No abstract provided.

Two-Hundred-Year Record Of Biogenic Sulfur In A South Greenland Ice Core (20d), P. Y. Whung, E. S. Saltzman, M. J. Spencer, Paul Andrew Mayewski, N. Gundestrup

Earth Science Faculty Scholarship

The concentration of methanesulfonic acid (MSA) was determined in a shallow south central Greenland ice core(20D). This study provides a high-resolution record of the DMS-derived biogenic sulfur in Greenland precipitation over the past 200 years. The mean concentration of MSA is 3.30 ppb(σ = 2.38 ppb,n = 1134). The general trend of MSA is an increase from 3.01 to 4.10 ppb between 1767 and 1900, followed by a steady decrease to 2.34 ppb at the present time. This trend is in marked contrast to that of non-sea-salt sulfate (nss SO₄^2-), which increases dramatically after 1900 due to …

Environments Of Aeolian Deposition In South-Central Nebraska During The Last Glacial Maximum, Zhao-Dong Feng, William C. Johnson, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

The Peoria loess of south-central Nebraska, deposited approximately during the last Glacial Maximum, can be subdivided into three zones: an upper laminated loess and a lower massive loess, separated by a dark gley zone in which bison bones and spruce charcoal are found. The lower Peoria unit is characterized by high organic matter content, relatively high bulk density, and common root channels. The upper Peoria unit has rhythmic patterns of two orders: strongly gleyed and weakly gleyed zones alternating in couplets about 2-5 m thick, and coarse- and fine-grained laminae of second order, about 2-4 mm thick. The strongly gleyed …

Geomorphic And Structural Features Of The Alliance 1º × 2º Quadrangle, Western Nebraska, Discernible From Synthetic-Aperture Radar Imagery And Digital Shaded-Relief Maps, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

The digital shaded-relief map of the United States and the synthetic-aperture radar map of the Alliance Nebraska 1º x 2º area prepared by the U.S. Geological Survey (USGS) in the former case and for the USGS in the latter show oriented landforms and lineaments in northwest Nebraska. Parallel and subparallel hills and valleys developed on different geologic materials ranging from shales through sandstones to loess and eolian sand appear to be wind erosional features subsequently modified by running water. The long axes of these hills and valleys generally trend between N40"W and N50"W. Similar features also occur across major areas …

Groundwater-Level Changes In Nebraska, 1992, Gregory V. Steele, Perry B. Wigley

Conservation and Survey Division

No abstract provided.

Resource Notes-Academic Year 1993-94

Conservation and Survey Division

No abstract provided.

Resource News-Spring 1994

Conservation and Survey Division

No abstract provided.

Cass County Test Hole Logs, Raymond R. Burchett, Frank A. Smith

Conservation and Survey Division

No abstract provided.

Clay County Test Hole Logs, Raymond R. Burchett

Conservation and Survey Division

No abstract provided.

Resource News-Summer 1994

Conservation and Survey Division

No abstract provided.

Location Of Registered Irrigation Wells In Nebraska As Of 1994

Conservation and Survey Division

No abstract provided.