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Seasonal Variability In Trace Metal Speciation And Vertical Redox Stratification Of Freshwater Lake And Marsh Sediments In The Kalamzoo River Watershed (Mi, Usa), Noah Tumusiime Ndenga Apr 2005

Seasonal Variability In Trace Metal Speciation And Vertical Redox Stratification Of Freshwater Lake And Marsh Sediments In The Kalamzoo River Watershed (Mi, Usa), Noah Tumusiime Ndenga

Masters Theses

This research was aimed at: 1) quantifying redox-sensitive parameters in order to study redox stratification of the upper freshwater sediments at Asylum Lake and Kleinstuck Marsh, 2) quantifying the speciation of metals (e.g., Pb, Mn, Fe, Cr, Cu, Zn, Co and Cd), particularly with respect to their association with Fe and Mn (hydr)oxide phases, and 3) assessing changes in redox stratification and metal speciation as a function of season in the sediments. Both the solid phase and sediment pore waters were collected to a depth of ~50cm. Pore waters were analyzed for redox-sensitive species and the sediment solid phase was …


The Effects Of Nutrient Concentrations On Macroinvertebrate Distributions In Georgia, Paula Michele Pollock Brossett Apr 2005

The Effects Of Nutrient Concentrations On Macroinvertebrate Distributions In Georgia, Paula Michele Pollock Brossett

Theses and Dissertations

Nutrients are considered the second largest nonpoint source pollutant in Georgia's running water ecosystems. Nutrients can naturally occur in low amounts and are typically increased in streams as a result of industry, agriculture, silviculture, and urbanization. In large amounts, nutrients can cause many problems to occur in the stream ecosystem. Macroinvertebrates have been established as good indicators for determining the level of impairment of a stream; however, not much research has been done on how nutrients affect macroinvertebrates in a stream. Approximately 225 reference and impaired streams were sampled over a 3 - year field season, (index period from September …


Producing Pulses In The Southern Agricultural Region, Peter White, Mark Seymour, Pam Burgess, Martin Harries Apr 2005

Producing Pulses In The Southern Agricultural Region, Peter White, Mark Seymour, Pam Burgess, Martin Harries

Bulletins 4000 -

The development of pulses in Western Australia has undergone tremendous advances over the past 12 years. From a tiny industry in the early 1990’s where the knowledge of both scientists and farmers was very limited, we now have a robust industry with production packages and improved varieties for all the grain legumes species that are well suited to our environment.

This book, which is both comprehensive and practical, collates much of the information gathered through pulse research and commercial experience over the past 10 years and will be valuable to all pulse growers, agronomists, students and industry advisors alike. The …


Use Of Tracers And Isotopes To Evaluate Vulnerability Of Water In Domestic Wells To Septic Waste, Ingrid M. Verstraeten, Gregory S. Fetterman, Michael T. Meyer, Thomas D. Bullen, Sonja Sebree Apr 2005

Use Of Tracers And Isotopes To Evaluate Vulnerability Of Water In Domestic Wells To Septic Waste, Ingrid M. Verstraeten, Gregory S. Fetterman, Michael T. Meyer, Thomas D. Bullen, Sonja Sebree

United States Geological Survey: Staff Publications

In Nebraska, a large number (>200) of shallow sand-point and cased wells completed in coarse alluvial sediments along rivers and lakes still are used to obtain drinking water for human consumption, even though construction of sand-point wells for consumptive uses has been banned since 1987. The quality of water from shallow domestic wells potentially vulnerable to seepage from septic systems was evaluated by analyzing for the presence of tracers and multiple isotopes. Samples were collected from 26 sand-point and perforated, cased domestic wells and were analyzed for bacteria, coliphages, nitrogen species, nitrogen and boron isotopes, dissolved organic carbon (DOC), …


The Benthic Community Of The Eastern Us Continental Shelf: A Literature Synopsis Of Benthic Faunal Resources, R. Allen Brooks, Carla N. Purdy, Susan S. Bell, Kenneth J. Sulak Mar 2005

The Benthic Community Of The Eastern Us Continental Shelf: A Literature Synopsis Of Benthic Faunal Resources, R. Allen Brooks, Carla N. Purdy, Susan S. Bell, Kenneth J. Sulak

United States Geological Survey: Staff Publications

The existing scientific literature on offshore benthic assemblages (OBA) residing along the US East and Gulf of Mexico continental shelf was reviewed. Identification was made of any associations between the dominant OBA and particular sediment types and/or bathymetry. Of special interest was the evaluation of reported effects of sand dredge/mining activities on the dominant OBA and recognition of data deficiencies. One hundred and twenty-two references were selected and classified as to type of study with pertinent results extracted. Polychaetes were predominantly cited as the principal infaunal taxa present in studies from both the Gulf of Mexico and US Atlantic coast. …


A Uintan (Late Middle Eocene) Flora And Fauna From The Uinta Basin, Utah, Stephen Dee Sandau Mar 2005

A Uintan (Late Middle Eocene) Flora And Fauna From The Uinta Basin, Utah, Stephen Dee Sandau

Theses and Dissertations

Late Middle Eocene time marks one of the most dynamic periods of the Paleogene in the western interior of North America. Analysis of an extensive, new collection of plant, invertebrate, and vertebrae fossils from the Uinta Formation in the Uinta Basin, south of Myton, Utah, USA, provides evidence of environmental change. Paleobotanical specimens are preserved in late stage Uinta Lake sediments and coarse-grained fluvial sediments which are stratigraphically 650 to 660 m above the Green River Formation. Deposition rates estimates of 18 to 55 cm/kyr, for Uinta Lake sediments in the Uinta Basin suggest a period of 1.18 Ma to …


Indicators Of Climate Change In The Northeast 2005, Adam Markham, Cameron P. Wake Mar 2005

Indicators Of Climate Change In The Northeast 2005, Adam Markham, Cameron P. Wake

The Sustainability Institute Publications

Climate changes. It always has and always will. What is unique in modern times is that human activities are now a significant factor causing climate to change. This is evident in the recent rise in key greenhouse gases, such as carbon dioxide (CO2), in the atmosphere, and in the recent increase in global temperatures in the lower atmosphere and in the surface ocean.

The evidence presented in this report clearly illustrates that climate in New England is also changing. Over the past 100 years, and especially the last 30 years, all of the climate change indicators for the region reveal …


Alfalfa: Crop For The Future, N. P. Martin, R. D. Hatfield, D. R. Mertens, P. J. Weimer Feb 2005

Alfalfa: Crop For The Future, N. P. Martin, R. D. Hatfield, D. R. Mertens, P. J. Weimer

Kentucky Alfalfa and Stored Forage Conference

Alfalfa use by dairy cattle has decreased in recent years because of excessive nonprotein nitrogen and low fiber digestibility. Ideal attributes for plant modification of alfalfa may include those that increase milk potential per acre and/or per ton, enhance digestible NDF, improve protein content and amino acid balance, improve agronomic traits for insect protection (safer forage supply), herbicide tolerance, virus resistance, drought tolerance, cold tolerance, improved mineral availability and enhanced yield. Progress in attaining these attributes will accelerate with the use of biotechnology. Livestock and hay enterprises will benefit from alfalfa that is less prone to contain mycotoxins or toxic …


Growing Alfalfa For Wildlife, Don Ball Feb 2005

Growing Alfalfa For Wildlife, Don Ball

Kentucky Alfalfa and Stored Forage Conference

Alfalfa has long been recognized as a superb forage crop, which is why it is widely grown for dairy cattle, horses, sheep, and many other types of domesticated forage-consuming animals. Reasons for its popularity include wide adaptation, excellent nutritive value, good yield potential, perennial growth habit, a long growing season, and the fact that (in association with Rhizobium bacteria) it is a nitrogen-fixing legume that does not require periodic applications of nitrogen fertilizer.


Alfalfa Hay For Horses (And Horse Owners!), Laurie Lawrence, Bryan Cassill Feb 2005

Alfalfa Hay For Horses (And Horse Owners!), Laurie Lawrence, Bryan Cassill

Kentucky Alfalfa and Stored Forage Conference

Alfalfa is one of the most common hays fed to horses in Kentucky. Other hays that are often used include timothy and orchardgrass. As a legume, alfalfa has many nutritional advantages over timothy or orchardgrass. Alfalfa hay contains more protein and calcium than grass hays and thus is an excellent source of these nutrients for broodmares and growing horses. Another legume that may be useful as a hay for horses is red clover. Nutritionally, red clover has many of the same advantages as alfalfa. However, red clover has some non-nutritional characteristics which have traditionally limited its popularity with horse owners. …


Sulfide Mineralization Within Modern, Deep-Sea Marine Sediments And Oxygenation Of The Early Earth, Matthew K. Thompson, Walter S. Borowski Feb 2005

Sulfide Mineralization Within Modern, Deep-Sea Marine Sediments And Oxygenation Of The Early Earth, Matthew K. Thompson, Walter S. Borowski

EKU Faculty and Staff Scholarship

The Earth’s atmosphere and oceans have not always been oxygenated. The exact pathway and timing of the oxygenation of the Earth’s early oceans is poorly constrained, although it appears that oxygenation was essentially complete by the beginning of the Cambrian (545 million years ago). Indeed, the appearance and diversification of the first animals may have been dependent on threshold levels of oxygen. Eventually we intend to use the sulfur isotopic composition of sulfide minerals (iron monosulfides and pyrite) present in sedimentary rocks to reconstruct the oxygenation of Proterozoic oceans, but first must strive to understand sulfide mineral formation in the …


Glossary Of Terms For Use With The 'A Million Hectares For The Future' Salinity Management Workshops, Rebecca Heath, Paul Raper Jan 2005

Glossary Of Terms For Use With The 'A Million Hectares For The Future' Salinity Management Workshops, Rebecca Heath, Paul Raper

Agriculture reports

This Glossary has been developed as part of the GRDC/NDSP-funded, 'A Million Hectares for the Future' project with support and input from key personnel from the Department of Agriculture, Western Australia.


A Student-Centered Project For Earth System History, Rebecca Teed Jan 2005

A Student-Centered Project For Earth System History, Rebecca Teed

Earth and Environmental Sciences Faculty Publications

This project is intended to replace some of the lectures that would ordinarily be necessary in a survey of Earth history over geologic time. The students will be taking the lecturer's place in front of the class, presenting some of the material to their colleagues. Students will work in groups on a single era or period. Each student role-plays an expert (such as an oceanographer) and works with teammates playing other sorts of experts (a biologist, a geologist, an atmospheric scientist). Their presentation will require them to do research. They will be constructing resource lists to keep track of how …


Avon Hotham Catchment Appraisal 2005, S Sharafi, H Lauk, Paul Galloway Jan 2005

Avon Hotham Catchment Appraisal 2005, S Sharafi, H Lauk, Paul Galloway

Resource management technical reports

This report summarises current information on risks and impacts to agricultural production and natural resources within the Avon Hotham study area. It then identifies suitable options to manage such risks. The Avon Hotham study area is 1.9 million hectares and is made up of three sub catchments: West Avon, South Avon and Hotham, in south west Western Australia. Among the risks and impacts discussed are rainfall, surface drainage; major land degredation hazards are subsurface compaction and acidification.


Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, Dana L. Hahn, Robert J. Dooling Jan 2005

Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, Dana L. Hahn, Robert J. Dooling

United States Geological Survey: Staff Publications

The auditory brainstem response (ABR), a measure of neural synchrony, was used to estimate auditory sensitivity in the eastern screech owl (Megascops asio). The typical screech owl ABR waveform showed two to three prominent peaks occurring within 5 ms of stimulus onset. As sound pressure levels increased, the ABR peak amplitude increased and latency decreased. With an increasing stimulus presentation rate, ABR peak amplitude decreased and latency increased. Generally, changes in the ABR waveform to stimulus intensity and repetition rate are consistent with the pattern found in several avian families. The ABR audiogram shows that screech owls hear best between …


New Approaches To Understanding The Mechanics Of Burgess Shale-Type Deposits: From The Micron Scale To The Global Picture, Robert Gaines, Mary L. Droser Jan 2005

New Approaches To Understanding The Mechanics Of Burgess Shale-Type Deposits: From The Micron Scale To The Global Picture, Robert Gaines, Mary L. Droser

Pomona Faculty Publications and Research

Cambrian Burgess Shale-type (BST) deposits are among the most significant deposits for understanding the “Cambrian explosion” because they contain the fossilized tissues of nonmineralized organisms and provide a substantially different window on the radiation of the Metazoa than is afforded by the more “typical” fossil record of skeletal parts of biomineralized organisms. Despite nearly a century of research, BST deposits remain poorly investigated as sedimentologic entities largely because they comprise fine-grained mudrocks. Here,we describe a new, integrative approach to understanding a single BST deposit, the middle Cambrian Wheeler Formation of Utah, which reveals a dynamic interplay of paleoenvironmental, paleoecologic, and …


Drought Preparedness Planning: Building Institutional Capacity, Donald A. Wilhite, Michael Hayes, Cody L. Knutson Jan 2005

Drought Preparedness Planning: Building Institutional Capacity, Donald A. Wilhite, Michael Hayes, Cody L. Knutson

National Drought Mitigation Center: Faculty Publications

Past attempts to manage drought and its impacts through a reactive, crisis management approach have been ineffective, poorly coordinated, and untimely, as illustrated by the hydro- illogical cycle in Figure 1. The crisis management approach has been followed in both developed and developing countries. Because of the ineffectiveness of this approach, greater interest has evolved in recent years in the adoption of a more proactive risk-based management approach in some countries (see Chapter 6). Other countries are striving to obtain a higher level of preparedness through development of national action programs that are part of the United Nations Convention to …


Agricultural Resource Priorities And Recommendations For The Avon River Basin Natural Resource Management Strategy, Paul D. Galloway, C E. Mcconnell, D W. Cummins, K Ohlsen Jan 2005

Agricultural Resource Priorities And Recommendations For The Avon River Basin Natural Resource Management Strategy, Paul D. Galloway, C E. Mcconnell, D W. Cummins, K Ohlsen

Resource management technical reports

This report for the Avon Natural Resource Management Strategy provides an assessment of the current status of land resources throughout the Avon River Basin in Western Australia. It identifies the sub-regions and landscape components of the area and the land resource assets. The greatest threats are salinity, soil acidification, subsurface compaction, waterlogging, water and wind erosion, and biosecurity.


Greenough Region Catchment Appraisal, Angela Stuart-Street, M Clarke Jan 2005

Greenough Region Catchment Appraisal, Angela Stuart-Street, M Clarke

Resource management technical reports

This report discusses a range of options for the Greenough region, which is comprised of eight shires including the Shires of Northampton, Chapman Valley, Mullewa, Greenough, Morawa, Irwin, Mingenew and Three Springs, and also the city of Geraldton. A range of options for reducing land degradation is discussed. Factors such as soil type, annual rainfall, enterprise mix and financial structure are also considered.


Taxonomic Relationships Among Phenacomys Voles As Inferred By Cytochrome B, M. Renee Bellinger, Susan M. Haig, Eric D. Forsman, Thomas D. Mullins Jan 2005

Taxonomic Relationships Among Phenacomys Voles As Inferred By Cytochrome B, M. Renee Bellinger, Susan M. Haig, Eric D. Forsman, Thomas D. Mullins

United States Geological Survey: Staff Publications

Taxonomic relationships among red tree voles (Phenacomys longicaudus longicaudus, P. l. silvicola), the Sonoma tree vole (P. pomo), the white-footed vole (P. albipes), and the heather vole (P. intermedius) were examined using 664 base pairs of the mitochondrial cytochrome b gene. Results indicate specific differences among red tree voles, Sonoma tree voles, white-footed voles, and heather voles, but no clear difference between the 2 Oregon subspecies of red tree voles (P. l. longicaudus and P. l. silvicola). Our data further indicated a close relationship between tree voles and albipes, …


Comparison Of Individual And Pooled Sampling Methods For Detecting Bacterial Pathogens Of Fish, Sonia Mumford, Chris Patterson, Joy Evered, Ray Brunson, Jay Levine, Jim Winton Jan 2005

Comparison Of Individual And Pooled Sampling Methods For Detecting Bacterial Pathogens Of Fish, Sonia Mumford, Chris Patterson, Joy Evered, Ray Brunson, Jay Levine, Jim Winton

United States Geological Survey: Staff Publications

Examination of finfish populations for viral and bacterial pathogens is an important component of fish disease control programs worldwide. Two methods are commonly used for collecting tissue samples for bacteriological culture, the currently accepted standards for detection of bacterial fish pathogens. The method specified in the Office International des Epizooties Manual of Diagnostic Tests for Aquatic Animals permits combining renal and splenic tissues from as many as 5 fish into pooled samples. The American Fisheries Society (AFS) Blue Book/US Fish and Wildlife Service (USFWS) Inspection Manual specifies the use of a bacteriological loop for collecting samples from the kidney of …


Perennial Grasses - Are They For Me? Workshop Development Guide For Facilitators, Trevor Lacey Jan 2005

Perennial Grasses - Are They For Me? Workshop Development Guide For Facilitators, Trevor Lacey

Agriculture reports

Farmers will be able to recognise landscape components on their farm that are at risk of salinity (current, imminent or future) and be aware of a range of available options available to them in managing this risk.


An Inventory Of Rangelands In Part Of The Broome Shire, Western Australia, W E. Cotching Jan 2005

An Inventory Of Rangelands In Part Of The Broome Shire, Western Australia, W E. Cotching

Technical Bulletins

The inventory of rangelands in part of the Broome Shire in Western Australia was undertaken by DAFWA between 1989 and 1990. It describes and maps the natural resources of the region’s pastoral leasehold land. This survey report provides a baseline record of the existence and condition of the natural area’s resources, to assist with the planning and implementation of land management practices. The report identified and described the condition of soils, landforms, vegetation, habitat, ecosystems, and declared plants and animals. It also assessed the impact of pastoralism and made land management recommendations. The survey of part of the Broome Shire …


Managing Grey Clays : To Maximise Production And Sustainability, Greg Hamilton, Peter Fisher, Matt Baimbridge, Jennifer Bignell, Jessica Sheppard, Rod Bowey Jan 2005

Managing Grey Clays : To Maximise Production And Sustainability, Greg Hamilton, Peter Fisher, Matt Baimbridge, Jennifer Bignell, Jessica Sheppard, Rod Bowey

Bulletins 4000 -

This bulletin discusses the identification, understanding and management of grey clay soils in the south-west of Western Australia.


Tapeworms Of Elasmobranchs (Part I) A Monograph On The Lecanicephalidea (Platyhelminthes, Cestoda), Kirsten Jensen Jan 2005

Tapeworms Of Elasmobranchs (Part I) A Monograph On The Lecanicephalidea (Platyhelminthes, Cestoda), Kirsten Jensen

Bulletin of the University of Nebraska State Museum (1924–2023)

This represents the first monographic and phylogenetic treatment of the order Lecanicephalidea. The main objective was to treat the Lecanicephalidea at the generic level, while providing information on morphology, taxonomic history, phylogenetic relationships, geographic distribution, and host associations of the group. Following an introduction to the morphology of the Lecanicephalidea, the phylogenetic placement of the group is addressed. This is followed by a review of the taxonomic history of the group and relationships within, including summaries of 29 previously used classification schemes. Despite the generic focus of this study, the taxonomic status of 137 previously recognized lecanicephalidean species was evaluated, …


Mercury Contamination Of Channel And Floodplain Sediments In Wilson Creek Watershed, Southwest Missouri, Willard E. Rodgers Ii Jan 2005

Mercury Contamination Of Channel And Floodplain Sediments In Wilson Creek Watershed, Southwest Missouri, Willard E. Rodgers Ii

Graduate Theses/Dissertations

Mercury (Hg) is a pollutant affecting aquatic environments and human health world wide. Sediments in urban streams can store Hg from historical industrial waste releases in channel and floodplain deposits. Subsequent erosion of these deposits can remobilize sediment-bound Hg impacting downstream receiving waters. This study describes the distribution of Hg in floodplain and channel sediments of Wilson Creek and its tributaries using geochemical sediment analysis and cesium-137 dating. The upper Wilson Creek watershed drains the southern two-thirds of Springfield, Missouri. Results indicate that Hg concentrations in overbank and active channel sediments along the entire stream length are elevated above the …


Marine Ice Modification Of Fringing Ice Shelf Flow, Christina L. Hulbe, R. Johnston, Ian R. Joughin, Ted A. Scambos Jan 2005

Marine Ice Modification Of Fringing Ice Shelf Flow, Christina L. Hulbe, R. Johnston, Ian R. Joughin, Ted A. Scambos

Geology Faculty Publications and Presentations

Locally derived ice is often observed to fill through-cutting rifts and uneven fronts in ice shelves. That ice may nucleate as fast ice at the shelf front, by growth at the sea surface within rifts, or by basal accretion. Here, we investigate the role of such ice in the flow of the Brunt Ice Shelf and adjacent Stancomb-Wills ice tongue, along the Caird Coast of Antarctica. Much of the shelf system is severely rifted, with locally derived ice filling the space between rift walls and around ice rafts. A series of numerical experiments that account for thermal properties of the …


Generalized Geologic Map For Land-Use Planning: Boone County, Kentucky, Richard A. Smath, Bart Davidson, Daniel I. Carey, John D. Kiefer, Ken Daniels Jan 2005

Generalized Geologic Map For Land-Use Planning: Boone County, Kentucky, Richard A. Smath, Bart Davidson, Daniel I. Carey, John D. Kiefer, Ken Daniels

Map and Chart--KGS

This map is not intended to be used for selecting individual sites. Its purpose is to inform land-use planners, government officials, and the public in a general way about geologic bedrock conditions that affect the selection of sites for various purposes. The properties of thick soils may supercede those of the underlying bedrock and should be considered on a site-to-site basis. At any site, it is important to understand the characteristics of both the soils and the underlying rock.


Amphibian Research And Monitoring Initiative: Concepts And Implementation, Paul Stephen Corn, Michael J. Adams, William A. Battaglin, Alisa L. Gallant, Daniel L. James, Melinda Knutson, Catherine A. Langtimm, John R. Sauer Jan 2005

Amphibian Research And Monitoring Initiative: Concepts And Implementation, Paul Stephen Corn, Michael J. Adams, William A. Battaglin, Alisa L. Gallant, Daniel L. James, Melinda Knutson, Catherine A. Langtimm, John R. Sauer

United States Geological Survey: Publications

This report provides the basis for discussion and subsequent articulation of a national plan for the Amphibian Research and Monitoring Initiative (ARMI). The authors were members of a task force formed from within the U.S. Geological Survey (USGS) that included scientists with expertise in biology, cartography, hydrology, and statistics. The assignment of the task force was to extend work begun by the National Amphibian Leadership Group. This group, composed of senior USGS scientists, managers, and external authorities, met in Gainesville, Florida, in February 20001. The product of this meeting was a document outlining the framework for a national program to …


Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, D. Caldwell Hahn, Robert J. Dooling Jan 2005

Auditory Brainstem Responses In The Eastern Screech Owl: An Estimate Of Auditory Thresholds, Elizabeth F. Brittan-Powell, Bernard Lohr, D. Caldwell Hahn, Robert J. Dooling

United States Geological Survey: Staff Publications

The auditory brainstem response (ABR), a measure of neural synchrony, was used to estimate auditory sensitivity in the eastern screech owl (Megascops asio). The typical screech owl ABR waveform showed two to three prominent peaks occurring within 5 ms of stimulus onset. As sound pressure levels increased, the ABR peak amplitude increased and latency decreased. With an increasing stimulus presentation rate, ABR peak amplitude decreased and latency increased. Generally, changes in the ABR waveform to stimulus intensity and repetition rate are consistent with the pattern found in several avian families. The ABR audiogram shows that screech owls hear best between …