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Probability Of Nitrate Contamination Of Recently Recharged Groundwaters In The Conterminous United States, Bernard Nolan, Kerie Hitt, Barbara Ruddy Jan 2002

Probability Of Nitrate Contamination Of Recently Recharged Groundwaters In The Conterminous United States, Bernard Nolan, Kerie Hitt, Barbara Ruddy

United States Geological Survey: Staff Publications

A new logistic regression (LR) model was used to predict the probability of nitrate contamination exceeding 4 mg/L in predominantly shallow, recently recharged groundwaters of the United States. The new model contains variables representing (1) N fertilizer loading (p < 0.001), (2) percent cropland-pasture (p < 0.001), (3) natural log of human population density (p < 0.001), (4) percent well-drained soils (p < 0.001), (5) depth to the seasonally high water table (p < 0.001), and (6) presence or absence of unconsolidated sand and gravel aquifers (p =0.002). Observed and average predicted probabilities associated with deciles of risk are well correlated (r2 = 0.875), indicating that the LR model fits the data well. The likelihood of nitrate contamination is greater in areas with high N loading and well-drained surficial soils over unconsolidated sand and gravels. The LR model correctly predicted the status of nitrate contamination in 75% of wells in a validation data set. Considering all wells used in both calibration and …


Wildlife Diseases: Crying Wolf Or Crying Shame?, Robert G. Mclean Jan 2002

Wildlife Diseases: Crying Wolf Or Crying Shame?, Robert G. Mclean

United States Geological Survey: Staff Publications

Diseases of North American wildlife are causing serious problems for wildlife, and some wildlife diseases pose health threats to humans and domestic animals. Information will be presented at this wildlife disease session to alert resource managers enough to consider disease as an important issue when managing wildlife populations. It will be a crying shame if appropriate actions are not taken to monitor diseases adequately and to prevent or control them to protect our wildlife resources.


Relating Net Nitrogen Input In The Mississippi River Basin To Nitrate Flux In The Lower Mississippi River: A Comparison Of Approaches, Gregory F. Mcisaac, Mark B. David, George Z. Gertner, Donald A. Goolsby Jan 2002

Relating Net Nitrogen Input In The Mississippi River Basin To Nitrate Flux In The Lower Mississippi River: A Comparison Of Approaches, Gregory F. Mcisaac, Mark B. David, George Z. Gertner, Donald A. Goolsby

United States Geological Survey: Staff Publications

A quantitative understanding of the relationship between terrestrial N inputs and riverine N flux can help guide conservation, policy, and adaptive management efforts aimed at preserving or restoring water quality. The objective of this study was to compare recently published approaches for relating terrestrial N inputs to the Mississippi River basin (MRB) with measured nitrate flux in the lower Mississippi River. Nitrogen inputs to and outputs from the MRB (1951 to 1996) were estimated from state-level annual agricultural production statistics and NOy (inorganic oxides of N) deposition estimates for 20 states that comprise 90% of the MRB. A model …


Intra-Annual Variation In The Stable Oxygen And Carbon And Trace Element Composition Of Sclerosponges, P. K. Swart, S. Thorrold, B. Rosenheim, A. Eisenhauer, C. G. A. Harriason, M. Grammer, C. Latkoczy Jan 2002

Intra-Annual Variation In The Stable Oxygen And Carbon And Trace Element Composition Of Sclerosponges, P. K. Swart, S. Thorrold, B. Rosenheim, A. Eisenhauer, C. G. A. Harriason, M. Grammer, C. Latkoczy

Biological Sciences Faculty Publications

This paper presents data to support the presence of (1) intra-annual signals in the chemical composition (δ18O and Sr/Ca) of the skeletons ofsclerosponges from the Bahamas and (2) variable rates of skeletal accretion. These conclusions are based on data obtained by using a microsampling method for the stable oxygen and carbon isotopes in which material was extracted at a resolution of one sample every 34 μm and a laser microprobe which obtained trace element data every 20 μm (Sr, Mg, and Pb). An age model was established using a combination of changes in the concentration of Pb, the …


Review Of Soil Conservation Legislation : Carnarvon Horticultural Area, Jean-Pierre Clement Jan 2002

Review Of Soil Conservation Legislation : Carnarvon Horticultural Area, Jean-Pierre Clement

Agriculture reports

Lower Gascoyne Management Strategy The Carnarvon horticultural area has suffered considerable erosion damage following flooding of the Gascoyne River. Factors contributing to the erosion include a move to greater vegetable production, the carrying out of unauthorised earthworks and general confusion about the laws that apply to land management and erosion control. With this context, the purpose of this report is: • to clarify the laws applying to erosion control in the Carnarvon horticultural area; • to identify the public authorities with management responsibility for erosion control; and • to suggest a model by which erosion controls and management responsibilities can …


Seasonal Migration Of Columbia Spotted Frogs (Rana Luteiventris) Among Complementary Resources In A High Mountain Basin, David S. Pilliod, Charles R. Peterson, Peter I. Ritson Dec 2001

Seasonal Migration Of Columbia Spotted Frogs (Rana Luteiventris) Among Complementary Resources In A High Mountain Basin, David S. Pilliod, Charles R. Peterson, Peter I. Ritson

United States Geological Survey: Staff Publications

Information on how animals partition their activities and travel among complementary resources, such as breeding or overwintering habitats, is needed for species conservation. In a mountain basin at 2500 m elevation in central Idaho, we studied the habitat use and movement patterns of 736 marked and 87 radio-tagged Columbia spotted frogs (Rana luteiventris) from 1995 to 1998. The goals of this study were to (i) identify and characterize R. luteiventris breeding, summer foraging, and overwintering habitats, (ii) describe the movement patterns of juvenile, male, and female R. luteiventris among these resources, and (iii …


Bulletin No. 37: Living Resources And Habitats Of The Lower Connecticut River, Glenn D. Dreyer, Marcianna Caplis Dec 2001

Bulletin No. 37: Living Resources And Habitats Of The Lower Connecticut River, Glenn D. Dreyer, Marcianna Caplis

Bulletins

No abstract provided.


1998 Debris Flows Near The Yakima River, Kittitas County, Washington—Some Geomorphic Implications, Martin R. Kaatz Dec 2001

1998 Debris Flows Near The Yakima River, Kittitas County, Washington—Some Geomorphic Implications, Martin R. Kaatz

Geography Faculty Scholarship

The geomorphic consequences of debris flows and their asso- ciated storms have been documented in many parts of the United States. Few, if any, have been studied and documented in central Washington. The importance of recurrent debris flows in sculpting Washington landscapes has not been generally recognized compared to other processes. Arid and semi-arid regions are particularly vulnerable to debris flows triggered by sudden intense thunderstorms. Most such areas are sparsely populated and eyewitnesses are uncommon. By contrast, semi-arid central Washington is relatively well popu- lated, and there are likely to be people who have observed the storms. Such witnesses …


Effects Of Binary Combinations Of Herbicides On Freshwater Algae, Jill K. Taylor Dec 2001

Effects Of Binary Combinations Of Herbicides On Freshwater Algae, Jill K. Taylor

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

No abstract provided.


Earth News, V25, Fall 2001, Department Of Earth Science, University Of Northern Iowa. Oct 2001

Earth News, V25, Fall 2001, Department Of Earth Science, University Of Northern Iowa.

Earth News

Inside this issue:

--- News from the Department Head
--- Earth Science Staff Activities
--- Earth Science Majors
--- 2001 Earth Science Graduates
--- Student Research Presentations
--- Student Internships
--- STORM: Science center for Teaching, Outreach, and Research on Meteorology
--- Studies in the Geology of Iowa for Teachers
--- Earth Science Student Assistants
--- Sigma Gamma Epsilon - Gamma Sigma Chapter
--- Gifts to the Department of Earth Science
--- 2001-2002 Scholarship and Award Recipients
--- 2001 Spring Trip Summary
--- Earth Science Seminar Series
--- Rapa Nui Expedition - March 2000
--- Alumni Profile - Larry J. …


Organic Vegetables : A Guide To Production, Steven Mccoy Oct 2001

Organic Vegetables : A Guide To Production, Steven Mccoy

Bulletins 4000 -

There appears to be considerable opportunity for the development of organic vegetable production in Western Australia for either fresh or processed product. While a number of growers are successfully producing relatively small quantities of organic vegetables for both domestic and export markets, few large scale commercial growers have sought to capitalise on this opportunity.

Consumer interest in organically grown vegetables has increased rapidly in recent years due largely to concerns relating to food safety, health and the environment. For more information on markets for organic vegetables refer to AGWEST publication “Market Prospects – Organic Carrots and other Vegetables”.


The Distribution Of Airborne Coal Dust In Soil Profiles Of Norfolk, Va And Its Implication For Arsenic Loading To These Soils, William Joseph Bounds Oct 2001

The Distribution Of Airborne Coal Dust In Soil Profiles Of Norfolk, Va And Its Implication For Arsenic Loading To These Soils, William Joseph Bounds

OES Theses and Dissertations

Norfolk, Virginia is home to the Northern Hemisphere's largest coal terminal the Lamberts Point Docks. The coal loading process of this terminal creates large amounts of coal dust, which subsequently is distributed throughout the local region by atmospheric transport and deposition. While the coal dust itself poses only minor health hazards, certain trace elements within the coal, particularly arsenic, may pose environmental as well as significant health hazards. Within coal, arsenic occurs primarily in the mineral pyrite. As pyrite in the coal dust is subsequently oxidized via exposure to the atmosphere and/or meteoric water, arsenic may be released to the …


Puerto Rican Karst - A Vital Resource, Ariel E. Lugo, Leopoldo Miranda Castro, Abel Vale, Tania Del Mar López, Enrique Hernández Prieto, Andrés García Martinó, Alberto R. Puente Rolón, Adrianne G. Tossas, Donald A. Mcfarlane, Tom Miller, Armando Rodríguez, Joyce Lundberg, John Thomlinson, José Colón, Johannes H. Schellekens, Olga Ramos, Eileen Helmer Aug 2001

Puerto Rican Karst - A Vital Resource, Ariel E. Lugo, Leopoldo Miranda Castro, Abel Vale, Tania Del Mar López, Enrique Hernández Prieto, Andrés García Martinó, Alberto R. Puente Rolón, Adrianne G. Tossas, Donald A. Mcfarlane, Tom Miller, Armando Rodríguez, Joyce Lundberg, John Thomlinson, José Colón, Johannes H. Schellekens, Olga Ramos, Eileen Helmer

WM Keck Science Faculty Papers

The limestone region of Puerto Rico covers about 27.5 percent of the island's surface and is subdivided into the northern, southern, and dispersed limestone areas. All limestone areas have karst features. The karst belt is that part of the northern limestone with the most spectacular surficial karst landforms. It covers 142,544 ha or 65 percent of the northern limestone. The karst belt is the focus of this publication, although reference is made to all limestone regions. The northern limestone contains Puerto Rico's most extensive freshwater aquifer, largest continuous expanse of mature forest, and largest coastal wetland, estuary, and underground cave …


Dye Tracing To Delineate Drainage Basins And Determine Groundwater Sensitivity, Mammoth Cave, Kentucky; With Special Reference To Potential Groundwater Contamination From Spills Along Interstate I-65, Arthur Capps Aug 2001

Dye Tracing To Delineate Drainage Basins And Determine Groundwater Sensitivity, Mammoth Cave, Kentucky; With Special Reference To Potential Groundwater Contamination From Spills Along Interstate I-65, Arthur Capps

Masters Theses & Specialist Projects

The Mammoth Cave System of south central Kentucky encompasses more than 560 km of surveyed cave passages. The largest groundwater basin (244 km2) found within this cave system emerges from the Turnhole Bend Spring on the Green River. During high flow conditions, water from this groundwater basin will spill over into the Echo River section of the cave. Previous research, including cave mapping and dye tracing (Quinlan and Ray, 1989; Currens and Ray, 1998; Coons, 1994), has delineated the boundaries of spring groundwater basins for numerous springs along the Green and Barren Rivers. These data showed that 60% of the …


Impact Of A Historical Translocation On Populations Of White-Tailed Deer Odocoileus Virginianus, Nathan Kendall Boddie Aug 2001

Impact Of A Historical Translocation On Populations Of White-Tailed Deer Odocoileus Virginianus, Nathan Kendall Boddie

Theses and Dissertations

Randomly amplified polymorphic DNA (RAPD) analysis was used to study the impact of a historical translocation event on populations of white-tailed deer in Georgia. The technique may also serve as a model by which management practices for other rare species can be studied. Populations from an original translocation source in Wisconsin, another Wisconsin population, and three populations in Georgia were sampled during management hunts. RAPD PCR was used to produce a genetic fingerprint for individuals of each population. Resulting band data were analyzed using PHYLIP genetic analysis software. A consensus tree of 100 bootstrapped replicates showed significant similarity between Georgia …


Historical Water-Quality Data For The High Plains Regional Ground-Water Study Area In Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, And Wyoming, 1930–98, David W. Litke Jul 2001

Historical Water-Quality Data For The High Plains Regional Ground-Water Study Area In Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, And Wyoming, 1930–98, David W. Litke

United States Geological Survey: Publications

The High Plains aquifer underlies 174,000 square miles in parts of eight States and includes eight primary hydrogeologic units, including the well-known Ogallala Formation. The High Plains aquifer is an important resource, providing water for 27 percent of the Nation’s irrigated agricul¬tural lands in an otherwise dry landscape. Since the 1980’s there has been concern over the sustainability of the aquifer due to water-level declines caused by substantial pumping. Water quality of the aquifer is a more recent concern. As part of the U.S. Geological Survey’s National Water-Quality Assessment Program, historical water-quality data have been gathered for the High Plains …


Application Of Neuro-Fuzzy Technique+2:9s To Predict Ground Water Vulnerability In Northwest Arkansas, B. Dixon, H. D. Scott, J. V. Brahana, A. Mauromoustakos Jul 2001

Application Of Neuro-Fuzzy Technique+2:9s To Predict Ground Water Vulnerability In Northwest Arkansas, B. Dixon, H. D. Scott, J. V. Brahana, A. Mauromoustakos

Arkansas Water Resources Center Technical Reports

Contamination of ground water has been a major concern in recent years of local, state and federal agencies involved with the management, quality, and quantity of water and their relationships with human health. The Springfield Plateau aquifer, which lies beneath the study area in northwest Arkansas, has been shown to have higher nitrate-N (NO3-N) concentrations than the national median. The dominant landuse (LULC) of this area is agriculture (primarily pasture/cattle and woodlands) and an encroaching urbanization. The major sources of nitrogen in the study area are poultry/cattle wastes, inorganic fertilizers (Peterson et. al., 1998) and septic filter fields. Many of …


Organic Grapes And Wine : A Guide To Production, Gerry Parlevliet, Steven Mccoy Jul 2001

Organic Grapes And Wine : A Guide To Production, Gerry Parlevliet, Steven Mccoy

Bulletins 4000 -

The tastebuds, health concerns and environmental conscience of affluent consumers are demanding more organically grown food than producers worldwide can supply. Growing consumer concerns about the effects of synthetic chemical pesticides and fertilisers on human health and the environment have boosted world trade in organic products by a rate of about 20-30 per cent a year for the past 10 years. World trade was estimated to be worth $US 21.6 billion in 2000 and is expected to reach US$100 billion by the year 2006.

The Australian market for organic products alone is valued at $200-$250 million - with exports estimated …


Apoptosis Following Peripheral Sensory Deafferentation In The Olfactory Blub Of Adult Zebrafish, Danio Rerio, Akiko M. Vankirk Jun 2001

Apoptosis Following Peripheral Sensory Deafferentation In The Olfactory Blub Of Adult Zebrafish, Danio Rerio, Akiko M. Vankirk

Masters Theses

Removal of the olfactory organ in the adult zebrafish results in a significant decrease in volume of the ipsilateral olfactory bulb. Our lab has been investigating the potential role of apoptosis in this phenomenon. My hypothesis is that cells in the adult olfactory bulb normally undergo minimal apoptosis and that apoptosis will increase when sensory stimulation is removed. The TUNEL method allowed detection of cells undergoing DNA-fragmentation, which indicates an apoptotic response. Double-label immunohistochemistry was used to mark which apoptotic cells are neurons by using antibody to Hu, a neuron specific protein. Triple-labeling with bis-benzirnide confirmed the apoptotic nature of …


Controls On Floc Size In A Continental Shelf Bottom Boundary Layer, Paul S. Hill, George Voulgaris, John H. Trowbridge May 2001

Controls On Floc Size In A Continental Shelf Bottom Boundary Layer, Paul S. Hill, George Voulgaris, John H. Trowbridge

Faculty Publications

Simultaneous in situ observations of floc size, waves, and currents in a continental shelf bottom boundary layer do not support generally accepted functional relationships between turbulence and floc size in the sea. In September and October 1996 and January 1997, two tripods were deployed in 70 m of water on the continental shelf south of Woods Hole, Massachusetts. On one a camera photographed particles in suspension 1.2 m above the bottom that had equivalent circular diameters larger than 250 um, and on the other, three horizontally displaced acoustic current meters measured flow velocity 0.35 m above the bottom. The …


The Efficacy Of Plant Residue Degradation Products On Phosphorus, Iron, Iodine, And Fluorine Bioavailability To Plants, Cheryl L. Mackowiak May 2001

The Efficacy Of Plant Residue Degradation Products On Phosphorus, Iron, Iodine, And Fluorine Bioavailability To Plants, Cheryl L. Mackowiak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Plant and animal wastes degrade in soils to form relatively stable humified compounds, which form ion complexes that affect the bioavailability of elements in the soil solution. Hydroponic studies with wheat and rice were conducted to characterize the effect of humic acid (HA) on phosphorus (P), iron (Fe), fluorine (F), and iodine (I) bioavailability. Ferrihydrite [Fe(OH)3] precipitation was greater on root surfaces without HA or synthetic chelates. Oxides such as ferrihydrite strongly adsorb P and provide exchange sites for metals. HA reduced this precipitate and increased P and Fe uptake.

Humic acid had no effect on F toxicity …


Addressing Uncertainty In Tmdls: Short Course At Arkansas Water Resources Center 2001 Annual Conference, Marty Matlock, Matthew Murawski Apr 2001

Addressing Uncertainty In Tmdls: Short Course At Arkansas Water Resources Center 2001 Annual Conference, Marty Matlock, Matthew Murawski

Arkansas Water Resources Center Technical Reports

Management of a critical natural resource like water requires information on the status of that resource. The US Environmental Protection Agency (EPA) reported in the 1998 National Water Quality Inventory that more than 291,000 miles of assessed rivers and streams and 5 million acres of lakes do not meet State water quality standards. This inventory represents a compilation of State assessments of 840,000 miles of rivers and 17.4 million acres of lakes; a 22 percent increase in river miles and 4 percent increase in lake acres over their 1996 reports. Siltation, bacteria, nutrients and metals were the leading pollutants of …


Esperance Downs Research Station : Rehabilitation Report, Harvey Jones Apr 2001

Esperance Downs Research Station : Rehabilitation Report, Harvey Jones

Resource management technical reports

Esperance Downs Research Station (EDRS) was established in 1949 as an experimental farm. Knowledge from trials on the station has been instrumental in development of agriculture throughout the Esperance region. However, land degradation and in particular secondary salinity became widespread by the 1980s. With potential for similar problems to develop in the region, the EDRS rehabilitation program began in 1990/91. This report details the objectives of this project along with implementation procedures and an assessment of its achievements.

The stated aim of the rehabilitation was 'To research and demonstrate economic methods of obtaining production from land affected by salinity, waterlogging …


Evidence Of Earliest Known Wildfires, Walter L. Cressler Iii Apr 2001

Evidence Of Earliest Known Wildfires, Walter L. Cressler Iii

Earth & Space Sciences Faculty Publications

No abstract provided.


Alfalfa As A Cash Hay Crop, John Nowak Feb 2001

Alfalfa As A Cash Hay Crop, John Nowak

Kentucky Alfalfa and Stored Forage Conference

Over the years we have all learned of the great potential alfalfa has as a forage crop in Kentucky. We have seen it used as hay, haylage and even pasture. Many aspects of our agri-business community have alfalfa as an important part of their business.


Alfalfa For Beef Cattle, W. Roy Burris Feb 2001

Alfalfa For Beef Cattle, W. Roy Burris

Kentucky Alfalfa and Stored Forage Conference

Alfalfa is sometimes said to be "too good" for beef cattle. Although it's nutritional value may sometimes exceed beef cows' needs, to dismiss it's potential for beef cattle would be a mistake. Alfalfa can be useful as a harvested feed or as a grazing crop.


Alfalfa For Dairy Cattle, Donna M. Amaral-Phillips Feb 2001

Alfalfa For Dairy Cattle, Donna M. Amaral-Phillips

Kentucky Alfalfa and Stored Forage Conference

Alfalfa is known as the queen of the forage crops and for good reasons. Alfalfa is an excellent forage for dairy cattle because it provides nutrients needed by dairy cows in a package which is highly digestible and cost effective. Alfalfa can be grazed directly by cattle or harvested as hay, haylage, or batage. Dairy farmers will purchase locally-grown hay if it is high quality (RFV greater than 150). When marketing cash hay one needs to understand that the quality of alfalfa greatly impacts milk production and economics of a dairy operation. This impact is felt even when as little …


Alfalfa Hay For Horses, Laurie Lawrence Feb 2001

Alfalfa Hay For Horses, Laurie Lawrence

Kentucky Alfalfa and Stored Forage Conference

Horse owners frequently mention cleanliness, color and cutting when it comes to choosing hay. Cleanliness should be the most important factor in selecting horse hay. Hay that contains dust or mold can inflame the respiratory tract. It is also possible for hay mold to affect other systems in the horse such as the digestive system and liver. Some horses suffer from a chronic respiratory condition that seriously impairs their ability to breathe normally. This condition, commonly known as heaves, worsens when horses are fed moldy or dusty hay. Horses with heaves are exercise intolerant and thus have little value except …


Reducing The Risk Of Bloat, Patty Scharko Feb 2001

Reducing The Risk Of Bloat, Patty Scharko

Kentucky Alfalfa and Stored Forage Conference

Bloat refers to excessive accumulation of gas in the rumen. Bloat results when an animal can not eructate or "belch up" gases produced in the process of rumen fermentation. The gas may be in the free form or may be mixed with rumen contents in the form of froth. It occurs both on pasture and in feedlots and can be a major cause of death in cattle wherever intensive farming is practiced. Additional losses can include decreased milk production and reduced rate of gain. Although legumes may increase the opportunity for bloat to occur, fear of bloat should not keep …


Grazing Alfalfa: Is It Right For You?, Jimmy C. Henning Feb 2001

Grazing Alfalfa: Is It Right For You?, Jimmy C. Henning

Kentucky Alfalfa and Stored Forage Conference

Grazing alfalfa can be a very profitable and valuable practice for many Kentucky farmers. How do you know if this practice will work for you? First, you must be able to grow alfalfa. Second, you must address the concerns that are specific to grazing alfalfa.