Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 30 of 34

Full-Text Articles in Physical Sciences and Mathematics

Speleothems As Proxy For The Carbon Isotope Composition Of Atmospheric Co2, M. Baskaran, R. V. Krishnamurthy Dec 1993

Speleothems As Proxy For The Carbon Isotope Composition Of Atmospheric Co2, M. Baskaran, R. V. Krishnamurthy

Environmental Science and Geology Faculty Research Publications

We have measured the stable isotope ratios of carbon in a suite of recent cave deposits (<200 >years) from the San Saba County, Texas, USA. The methodology for dating these deposits using excess 210Pb was recently established [Baskaran and Iliffe, 1993]. The carbon isotope ratios of these samples, spanning the time period ∼1800–1990 AD, reflect the carbon isotope ratio of atmospheric CO2 for the same period. The pathways by which the δ13C of atmospheric CO2 is imprinted on these speleothems can be explained using a model developed by Cerling (1984). The results suggest that the …


Catchment Management Report Prepared For The Dalwallinu Pithara Land Conservation District, Jenny Borger Dec 1993

Catchment Management Report Prepared For The Dalwallinu Pithara Land Conservation District, Jenny Borger

Agriculture reports

The Pithara-Dalwallinu Land Conservation District was initiated in 1985. Over the past seven years the committee has carried out various trials, demonstrations and field days. It was decided in 1989 to go along the road of whole catchment planning utilising the Geographic Information System (GIS). It now gives me great pleasure to see the information collected over the last two years, presented as a workable document. I hope now that many farmers within the LCD will be able to use this report to aid in planning and future development of their most valued asset The Land. The Catchment Report is …


A Comparison Of No And N20 Production By The Autophic Nitrifier Nitrosomonas Europaea And The Heterotrophic Nitrifier Alcaligenes Faecalis, Iris C. Anderson, Mark Poth, Julie Homstead, David J. Burdige Nov 1993

A Comparison Of No And N20 Production By The Autophic Nitrifier Nitrosomonas Europaea And The Heterotrophic Nitrifier Alcaligenes Faecalis, Iris C. Anderson, Mark Poth, Julie Homstead, David J. Burdige

OES Faculty Publications

Soil microorganisms are important sources of the nitrogen trace gases NO and N2O for the atmosphere. Present evidence suggests that autotrophic nitrifiers such as Nitrosomonas europaea are the primary producers of NO and N2O in aerobic soils, whereas denitrifiers such as Pseudomonas spp. or Alcaligenes spp. are responsible for most of the NO and N2O emissions from anaerobic soils. It has been shown that Alcaligenes faecalis, a bacterium common in both soil and water, is capable of concomitant heterotrophic nitrification and denitrification. This study was undertaken to determine whether heterotrophic nitrification might be …


Epa's Map Of Radon Zones, Nebraska, Sharon W. White, Lisa Ratcliff, Kirk Maconaughey, R. Thomas Peake, Dave Rowson, Steve Page, Linda C. S. Gundersen, R. Randall Schumann, James K. Otton, Doug Owen, Russell Dubiel, Kendell Dickinson, Sandra L. Szarzi Sep 1993

Epa's Map Of Radon Zones, Nebraska, Sharon W. White, Lisa Ratcliff, Kirk Maconaughey, R. Thomas Peake, Dave Rowson, Steve Page, Linda C. S. Gundersen, R. Randall Schumann, James K. Otton, Doug Owen, Russell Dubiel, Kendell Dickinson, Sandra L. Szarzi

United States Environmental Protection Agency: Staff Publications

Sections 307 and 309 of the 1988 Indoor Radon Abatement Act (IRAA) direct EPA to identify areas of the United States that have the potential to produce elevated levels of radon. EPA, the U.S. Geological Survey (USGS), and the Association of, American State Geologists (AASG) have worked closely over the past several years to produce a series of maps and documents which address these directives. The EPA Map of Radon Zones is a compilation of that work and fulfills the requirements of sections 307 and 309 of IRAA. The Map of Radon Zones identifies, on a county-by-county basis, areas of …


Geology, Geologic Time And Nebraska, Marvin P. Carlson Aug 1993

Geology, Geologic Time And Nebraska, Marvin P. Carlson

Conservation and Survey Division

No abstract provided.


Nutrient Content Of Runoff Water From Rice Fields, C. E. Wilson Jr., P. A. Moore Jr., R. J. Norman, B. R. Wells Jun 1993

Nutrient Content Of Runoff Water From Rice Fields, C. E. Wilson Jr., P. A. Moore Jr., R. J. Norman, B. R. Wells

Technical Reports

Current perception is that nutrient runoff from croplands is a significant contributor to poor water quality in some areas. While extensive research has been conducted to survey and ameliorate this problem for several upland crops, little work has been done to evaluate the problem with flooded rice (Oryza sativa, L.) soils. Since rice production utilizes a major portion of the total irrigation water usage for certain areas, it is important to understand the contribution of rice production to non-point source N and P in surface water. Several production fields were selected to evaluate the concentrations of nutrients in the floodwater …


The Influence Of Reservoir Basin Morphometry On Phytoplankton Community Structure, Richard L. Meyer, G. Keith Trost Jun 1993

The Influence Of Reservoir Basin Morphometry On Phytoplankton Community Structure, Richard L. Meyer, G. Keith Trost

Technical Reports

The research protocol was designed to compare three reservoirs with similar physical environments but different morphometry. Three reservoirs on the western edge of the Ozark uplift were selected because of their similar substrate and climatic condition. The reservoirs primarily differed in morphometry. Two of the reservoirs were of identical size, Bob Kidd and Prairie Groves Lakes, but of different configuration, semicircular and linear, respectively. The bifurcated lake, Lincoln Lake, was of smaller size. Each lake is dimictic. Each of the lakes were nitrate-N limited while soluble reactive phosphorus-P is available and not restricting the growth of phytoplankton. Although the pattern …


Computer Simulation Model Calibration And Validation For Prediction Of Water Quality Impacts Of Poultry Waste Disposal, D. R. Edwards, T. C. Daniel Jun 1993

Computer Simulation Model Calibration And Validation For Prediction Of Water Quality Impacts Of Poultry Waste Disposal, D. R. Edwards, T. C. Daniel

Technical Reports

Runoff and water quality data collected from two pairs of grazed fields in northwestern Arkansas were analyzed to support efforts to model runoff quality from areas receiving poultry manure and other fertilizer sources. The monitoring period described in this report was September 1, 1991 to April 30, 1993. One of each pair of fields was fertilized with inorganic fertilizer, and the other received either poultry litter or manure. Losses of fertilizer constituents were quite low from an agronomic standpoint, ranging from approximately 2-11 kg N/ha/year and 0.5-4.1 kg P04-P/ha/year. Annual losses of fertilizer constituents were dominated by only a small …


Effect Of Drying On Cyromazine Loss From Surface-Applied Caged-Layer Manure, T. C. Daniel, D. H. Pote, D. R. Edwards Jun 1993

Effect Of Drying On Cyromazine Loss From Surface-Applied Caged-Layer Manure, T. C. Daniel, D. H. Pote, D. R. Edwards

Technical Reports

In Arkansas, much of the environmental concern related to water quality has focused on the high volume of poultry fecal waste spread on the surf ace of local pastures to fertilize forage grass. Cyromazine (N-cyclopropyl-1,3,5-triazine-2,4,6- triamine), a feed-through larvicide used to control house flies (Musca domestica), is often a component of caged-layer manure. Cyromazine is quite soluble and stable in water, and previous research has shown that it can be readily washed from pasture plots by intense rainfall. Therefore, a study was conducted to evaluate increased drying time as a best management practice technique for reducing cyromazine runoff losses from …


Prediction And Management Of Sediments Load And Phosporus In The Beaver Reservoir Watershed Using A Geographic Information System, J. M. Mckimmey, H. D. Scott Jun 1993

Prediction And Management Of Sediments Load And Phosporus In The Beaver Reservoir Watershed Using A Geographic Information System, J. M. Mckimmey, H. D. Scott

Technical Reports

A study was conducted to compile a GIS database for the Beaver Reservoir Watershed and then use the database to run the Universal Soil Loss Equation and the Phosphorus Index Model on the War Eagle Creek Watershed, a portion of the Beaver Reservoir Watershed database. Characterization of the spat i a 1 properties of the primary attributes compiled for the watershed were reported. In addition, water quality samples taken from War Eagle Creek were analyzed for relationships across the watershed. Erosion in the watershed was lower than expected with well vegetated and fertilized pastures contributing to the reduction of annual …


Arkansas Rice Research Studies 1992, B. R. Wells Jun 1993

Arkansas Rice Research Studies 1992, B. R. Wells

Arkansas Agricultural Experiment Station Research Series

The research reports in this publication represent one year of results; therefore, these results should not be used as a basis for longterm recommendations. Several research reports in this publication dealing with soil fertility also appear in Arkansas Soil Fertility Studies 1992, Arkansas Agricultural Experiment Station Research Series 425. This duplication is the result of the overlap in research coverage between the two series and our effort to inform Arkansas rice producers of all the research being conducted with funds from the rice check-off.


Information And Regulations Pertaining To Industrial Minerals In Nebraska, Raymond R. Burchett Jun 1993

Information And Regulations Pertaining To Industrial Minerals In Nebraska, Raymond R. Burchett

Conservation and Survey Division

No abstract provided.


The Mobrup Catchment Working Plan - A Resource Inventory And Strategies, Steven Garrad Jun 1993

The Mobrup Catchment Working Plan - A Resource Inventory And Strategies, Steven Garrad

Soil conservation survey collection

The Mobrup LCDC has persevered for three years with its efforts to produce a catchment plan. They readily acknowledge that their work is just beginning as they now wrestle with this working plan to form something which will have application on each individual's enterprise to ensure a sustainable future for this catchment.This report is a collation of their ideas, an inventory of works done in the catchment and the best advice which research and local knowledge can provide.


Age Determination Of Recent Cave Deposits Using Excess 210Pb - A New Technique, M. Baskaran, Thomas M. Iliffe Apr 1993

Age Determination Of Recent Cave Deposits Using Excess 210Pb - A New Technique, M. Baskaran, Thomas M. Iliffe

Environmental Science and Geology Faculty Research Publications

Cave deposits have been widely used as proxy recorders in deciphering palaeoclimate during the last glacial/interglacial maxima (∼ 120 ka) [Harmon et al., 1975; Atkinson et al., 1978; Goede and Harmon, 1983; Ayliffe and Veeh, 1989]. Palaeoclimatic studies of cave deposits for the past 1–1000 yr time scale require a precise dating technique, that until now has been lacking. Due to the multiple sources of carbon in speleothems, 14C dates obtained for recently deposited calcite are highly variable and thus, 14C dating techniques are not suitable to obtain speleothem ages for the past 1–1000 years.

Here, we show …


Flat Water: A History Of Nebraska And Its Water, Robert D. Kuzelka, Charles A. Flowerday, Robert N. Manley, Bradley C. Rundquist, Sally J. Herrin Mar 1993

Flat Water: A History Of Nebraska And Its Water, Robert D. Kuzelka, Charles A. Flowerday, Robert N. Manley, Bradley C. Rundquist, Sally J. Herrin

Conservation and Survey Division

No abstract provided.


The Origin And Evolution Of The Southern Snake Range Decollement, East Central Nevada, Allen J. Mcgrew Feb 1993

The Origin And Evolution Of The Southern Snake Range Decollement, East Central Nevada, Allen J. Mcgrew

Geology Faculty Publications

Regional and local stratigraphic, metamorphic, and structural constraints permit reconstruction of the southern Snake Range extensional deformational system in east central Nevada. The dominant structure of the range, the southern Snake Range décollement (SSRD), operated during Oligocene and Miocene extensional deformation to exhume a footwall of multiply deformed metasedimentary and plutonic rocks. Intrusion of three plutons (∼160 Ma, 79.1 ± 0.5 Ma, and 36 ± 1 Ma, respectively) and development of two cleavages preceded the onset of extensional deformation. Plastic deformation of lower plate metasedimentary rocks accompanied the early phases of regional extension and produced bedding-parallel grain shape foliations and …


Conservation For Production : Kings Rocks Catchment Report, William Oldfield Feb 1993

Conservation For Production : Kings Rocks Catchment Report, William Oldfield

Agriculture reports

The aim of this report is to bring together current information on the land and ideas which will provide landholders of the King Rocks catchment group with a basis to make more informed decisions about managing the land. The report contains information on how the landscape was formed, how areas become degraded, what are the present recommended ways of fixing land degradation and what are the most productive means of farming the land.


Soil Testing: Field, Sample And Laboratory Variability, Lloyd W. Murdock, Dan Kirkland, Phil Gillespie, Tim Gray Jan 1993

Soil Testing: Field, Sample And Laboratory Variability, Lloyd W. Murdock, Dan Kirkland, Phil Gillespie, Tim Gray

Soil Science News and Views

Soil testing has advanced as a science and has become a tool widely used in making fertilizer recommendations. One of the basic components for ensuring reliability of recommendations is calibration of soil test results to determine the proper match of fertilizer recommendations with the soil test level for each nutrient and crop. Generally, calibration has been accomplished on small plot areas and is quite accurate. Even though there is nutrient variability within small areas, the potential for variability is much greater on a field basis. An important factor in making reliable fertilizer recommendations is the assumption that the soil sample …


Broiler Litter For Topdressing Tall Fescue, Monroe Rasnake, David Watson Jan 1993

Broiler Litter For Topdressing Tall Fescue, Monroe Rasnake, David Watson

Soil Science News and Views

A test was started in Princeton in 1991 to observe the response of tall fescue to applications of nitrogen fertilizer and broiler litter. Five treatments were used: two and four tons of litter per acre, 100 lbs nitrogen (half in May and half in July), 100 lbs nitrogen plus soil test recommended rates of phosphate and potash (only 55 lbs of Phosphate applied in 1991) and a check which had no nutrients applied. The treatments began in May 1991 on an established stand of tall fescue on a fragipan soil at the U.K. Research and Education Center in Princeton.


Factors Affecting Color Of Cured Burley Leaf, J. L. Sims, Gary K. Palmer, Kenneth L. Wells Jan 1993

Factors Affecting Color Of Cured Burley Leaf, J. L. Sims, Gary K. Palmer, Kenneth L. Wells

Soil Science News and Views

Much interest has been shown by tobacco growers during recent months in fertilization and or other management practices that can be used to produce darker and redder cured leaf of burley tobacco. The purpose of this newsletter is to summarize what we know about some of the factors which affect color of cured leaf.


Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V1, United States Forest Service Jan 1993

Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V1, United States Forest Service

Environmental Assessments (NV)

No abstract provided.


Nebraska Mineral Operations Review, 1992, R. R. Burchett, Duane A. Eversoll Jan 1993

Nebraska Mineral Operations Review, 1992, R. R. Burchett, Duane A. Eversoll

Conservation and Survey Division

No abstract provided.


Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V2, United States Forest Service Jan 1993

Final Oil And Gas Leasing Environmental Impact Statement [Microform] : Grand Mesa, Uncompahgre And Gunnison National Forests V2, United States Forest Service

Environmental Assessments (NV)

No abstract provided.


Data Set And Code Definitions For Soil Profile Description : Dawa Regional Mapping Program, B R. Purdie Jan 1993

Data Set And Code Definitions For Soil Profile Description : Dawa Regional Mapping Program, B R. Purdie

Resource management technical reports

No abstract provided.


North Stirling Land Conservation District - Soils Manual, Justin Hardy, Peter J. Tille Jan 1993

North Stirling Land Conservation District - Soils Manual, Justin Hardy, Peter J. Tille

Soil conservation survey collection

The North Stirling Land Conservation District is located between Katanning and Albany on the northern edge of the Stirling Ranges in south-western Western Australia.It includes parts of the Shires of Cranbrook and Tambellup, covering approximately 100,000ha of the catchment of the North Stirling basin. The basin is a flat area formed on Eocene sediments with poorly defined drainage lines and many salt lakes. It is surrounded by low granite and sandstone hills. The climate is Mediterranean, with cool wet winters and hot dry summers. Average annual rainfall ranges from 375-500 mm per annum. There is very little surface or underground …


Geology And Mineral Resources Of Boone, Greeley, Nance, And Wheeler Counties, Nebraska, Raymond R. Burchett Jan 1993

Geology And Mineral Resources Of Boone, Greeley, Nance, And Wheeler Counties, Nebraska, Raymond R. Burchett

Conservation and Survey Division

No abstract provided.


Resource News-July/August 1993 Jan 1993

Resource News-July/August 1993

Conservation and Survey Division

No abstract provided.


Uranium Deposits In Nebraska, R. R. Burchett Jan 1993

Uranium Deposits In Nebraska, R. R. Burchett

Conservation and Survey Division

No abstract provided.


Niobrara River Basin Geological References, Including Parts Of South Dakota Both In And Outside Of The Basin, Robert F. Diffendal Jr. Jan 1993

Niobrara River Basin Geological References, Including Parts Of South Dakota Both In And Outside Of The Basin, Robert F. Diffendal Jr.

Conservation and Survey Division

Includes Niobrara River Basin geological references, including parts of South Dakota both in and outside of the basin.


Cedar County Test Hole Logs, Raymond R. Burchett Jan 1993

Cedar County Test Hole Logs, Raymond R. Burchett

Conservation and Survey Division

No abstract provided.