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Geographic Information System Methodologies To Evaluate Relationships Between Land Use And Groundwater Quality In South Central Kentucky, Rhonda Pfaff Feb 2003

Geographic Information System Methodologies To Evaluate Relationships Between Land Use And Groundwater Quality In South Central Kentucky, Rhonda Pfaff

Masters Theses & Specialist Projects

The development of Geographic Information System (GIS) technology has provided techniques for a holistic approach to the study of karst groundwater contamination. While karst groundwaters supply water to a large percentage of the earth's population, its complex environments often have lacked the scientific examination and conservation measures typical of non-karst regions. In this study, GIS methodologies were explored to examine the relationships between land-use and water quality in karst watersheds. Eight watersheds throughout southern and western Kentucky were examined. The study areas included the Mammoth Cave Karst Aquifer, which is the watershed that drains the Mammoth Cave System, and seven …

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A Watershed Analysis Of Threemile Pond: Implications For Water Quality And Land Use Management, Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College Jan 2003

A Watershed Analysis Of Threemile Pond: Implications For Water Quality And Land Use Management, Colby Environmental Assessment Team, Colby College, Problems In Environmental Science Course (Biology 493), Colby College

Colby College Watershed Study: Threemile Pond (2003)

The 2003 Colby Environmental Assessment Team chose to study the Threemile Pond watershed. The Threemile Pond watershed is located in Vassalboro, China., Windsor, and Augusta, Maine. Threemile Pond is a popular site for recreation and is home to a wide range of flora and fauna. Like all other lakes in Maine, it is a young lake. However, intensive human activity in the watershed contributes a substantial amount of nutrients and the lake has algal blooms annually in the summer months. The purpose of this study was to assess the impact of land use and development on the water quality of …

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Inverse Modeling Of Btex Dissolution And Biodegradation At The Bemidji, Mn Crude-Oil Spill Site, Hedeff I. Essaid, Isabelle M. Cozzarelli, Robert P. Eganhouse, William N. Herkelrath, Barbara A. Bekins, Geoffrey N. Delin, Win Butler Jan 2003

Inverse Modeling Of Btex Dissolution And Biodegradation At The Bemidji, Mn Crude-Oil Spill Site, Hedeff I. Essaid, Isabelle M. Cozzarelli, Robert P. Eganhouse, William N. Herkelrath, Barbara A. Bekins, Geoffrey N. Delin, Win Butler

United States Geological Survey: Staff Publications

The U.S. Geological Survey (USGS) solute transport and biodegradation code BIOMOC was used in conjunction with the USGS universal inverse modeling code UCODE to quantify field-scale hydrocarbon dissolution and biodegradation at the USGS Toxic Substances Hydrology Program crude-oil spill research site located near Bemidji, MN. This inverse modeling effort used the extensive historical data compiled at the Bemidji site from 1986 to 1997 and incorporated a multicomponent transport and biodegradation model. Inverse modeling was successful when coupled transport and degradation processes were incorporated into the model and a single dissolution rate coefficient was used for all BTEX components. Assuming a …

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Preliminary Investigations Of Seasonal Changes In The Geochemical Evolution Of The Logdson River, Mammoth Cave, Kentucky, Chris Groves, Darlene M. Anthony, Joe Meiman Jan 2003

Preliminary Investigations Of Seasonal Changes In The Geochemical Evolution Of The Logdson River, Mammoth Cave, Kentucky, Chris Groves, Darlene M. Anthony, Joe Meiman

Earth, Environmental, and Atmospheric Sciences Faculty Publications

Many geochemical studies have been made of karst waters worldwide. Most data that provide the framework for our current understanding of the evolution of karst waters have come from sampling at discrete times and locations, such as springs or wells. Relatively few studies have been made of the geochemical evolution of groundwater as it moves through an open flow system. This paper addresses the seasonal changes in the geochemistry of the Logsdon River conduit as it passes through nearly 10km of the carbonate aquifer of south-central Kentucky . The most important control on the ability of groundwaters to dissolve limestone …

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Natural Resource Management Issues In The Agricultural Zone Of Western Australia : South West Region, B Nicholas, Paul Galloway, Peter J. Tille, Angela Stuart-Street, Heather M. Percy Jan 2003

Natural Resource Management Issues In The Agricultural Zone Of Western Australia : South West Region, B Nicholas, Paul Galloway, Peter J. Tille, Angela Stuart-Street, Heather M. Percy

Resource management technical reports

Provides and analysis of current pressures on agricultural resources of the South West region of Western Australia. Differing ranges of risks are shown for different degradation issues because of various impacts. Each natural resource management issues covers nature and extent of susceptibility, impacts on agriculture and the environment, management options and effectiveness of management options.

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Tracer/Time-Lapse Radar Imaging Test At The Boise Hydrogeophysical Research Site, Warren Barrash, Michael D. Knoll, David W. Hyndman, Tom Clemo, Edward C. Reboulet, Elisabeth M. Hausrath Jan 2003

Tracer/Time-Lapse Radar Imaging Test At The Boise Hydrogeophysical Research Site, Warren Barrash, Michael D. Knoll, David W. Hyndman, Tom Clemo, Edward C. Reboulet, Elisabeth M. Hausrath

Geosciences Faculty Publications and Presentations

A combined tracer and time-lapse radar imaging experiment was conducted in the unconfined coarse fluvial aquifer at the Boise Hydrogeophysical Research Site in August, 2001. Two tracers (bromide and uranine) were injected to form a plume over a 4-m interval that spanned the contact between hydrostratigraphic units with contrasting permeability. The tracer plume traveled 6.9 m to well B6, passing through well A1 instrumented with 20 sampling zones over a 5-m interval that spanned the injection interval. Radar tomographic data were collected periodically on cross-sectional and longitudinal planes, two of which passed through well A1 for quantitative calibration of radar …

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A Reinterpretation Of The Small Captorhinid Reptile Captorhinikos Parvus Olson As A New Genus, Reanalysis Of Its Cranial Anatomy, And A Phylogenetic Analysis Of The Basal Reptilian Family Captorhinidae, Gavan Mcbride Albright Jan 2003

A Reinterpretation Of The Small Captorhinid Reptile Captorhinikos Parvus Olson As A New Genus, Reanalysis Of Its Cranial Anatomy, And A Phylogenetic Analysis Of The Basal Reptilian Family Captorhinidae, Gavan Mcbride Albright

Theses Digitization Project

The cranial anatomy of the basal captorhinid reptile Captorhinikos parvus (Reptilia, Captorhinidae), is reinterpreted here based on analysis of a group of new specimens recovered subsequent to its original diagnosis as well as further analysis of the original specimens utilized in E.C. Olson's original characterization of the species. Structural features inconsistent with the generic description suggest the redefinition of C. parvus as a new genus, Rhodotheratus parvus. Analyses of basal members and selected derived members support the characterization of Rhodotheratus as a distinct taxon.

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Changes In The Timing Of High River Flows In New England Over The 20th Century, G. A. Hodgkins, R. W. Dudley, T. G. Huntington Jan 2003

Changes In The Timing Of High River Flows In New England Over The 20th Century, G. A. Hodgkins, R. W. Dudley, T. G. Huntington

United States Geological Survey: Staff Publications

The annual timing of river flows is a good indicator of climate-related changes, or lack of changes, for rivers with long-term data that drain unregulated basins with stable land use. Changes in the timing of annual winter/spring (January 1 to May 31) and fall (October 1 to December 31) center of volume dates were analyzed for 27 rural, unregulated river gaging stations in New England, USA with an average of 68 years of record. The center of volume date is the date by which half of the total volume of water for a given period of time flows past a …

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Soil Survey Of Grand Staircase- Escalante National Monument Area, Parts Of Kane And Garfield Counties, Utah, United States Department Of Agriculture, Natural Resources Conservation Service Jan 2003

Soil Survey Of Grand Staircase- Escalante National Monument Area, Parts Of Kane And Garfield Counties, Utah, United States Department Of Agriculture, Natural Resources Conservation Service

All U.S. Government Documents (Utah Regional Depository)

This soil survey contains information that affects land use planning in this survey area. It contains predictions of soil behavior for selected land uses. The survey also highlights soil limitations, improvements needed to overcome the limitations and the impact of selected land uses on the environment. This soil survey is designed for many different users. Farmers, ranchers, foresters and agronomists can use it to evaluate the potential of the soil and the management needed for maximum food and fiber production. Planners, community officials, engineers, developers, builders and home buyers can use the survey to plan land use, select sites for …

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Monitoring Trends In Bat Populations Of The United States And Territories: Problems And Prospects, T.J. O'Shea, M. A. Bogan Jan 2003

Monitoring Trends In Bat Populations Of The United States And Territories: Problems And Prospects, T.J. O'Shea, M. A. Bogan

United States Geological Survey: Publications

Bats are ecologically and economically important mammals. The life histories of bats (particularly their low reproductive rates and the need for some species to gather in large aggregations at limited numbers of roosting sites) make their populations vulnerable to declines. Many of the species of bats in the United States (U.S.) and territories are categorized as endangered or threatened, have been candidates for such categories, or are considered species of concern. The importance and vulnerability of bat populations makes monitoring trends in their populations a goal for their future management. However, scientifically rigorous monitoring of bat populations requires well-planned, statistically …

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Geologic Studies Of Mercury By The U.S. Geological Survey Jan 2003

Geologic Studies Of Mercury By The U.S. Geological Survey

United States Geological Survey: Publications

A liquid at room temperature, mercury is a unique metal with unusual properties. Elemental mercury has long been used in thermometers because it responds to changes in temperature. In fact, mercury’s many diverse properties have made it useful for many products. Mercury is a good metallic conductor with a low electrical resistivity; it has been used in electrical products including electrical wiring and switches, fluorescent lamps, mercury batteries, and thermostats (Eisler, 1987). Mercury also is used in navigational instruments to measure changes in temperature and pressure. In the medical field, mercury is used as a component in dental fillings and …

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Review Of Population Viability Analysis, Mark W. Miller Jan 2003

Review Of Population Viability Analysis, Mark W. Miller

United States Geological Survey: Staff Publications

Population viability analysis (PVA) historically has been used to estimate the probability that a population will become extinct within a given time period. More recently, PVA has been used to evaluate alternative management strategies. Some might even say PVA gave rise to conservation biology. Nevertheless, PVA has been heavily criticized. This is the second book to present a synthesis and address those concerns. It does so extremely well.

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Genetic Variation In Black Bears In Arkansas And Louisiana Using Microsatellite Dna Markers, Ildiki Csiki, Cynthia Lam, Audie Key, Erica Coulter, Joseph D. Clark, Richard M. Pace Iii, Kimberley G. Smith, Douglas D. Rhoads Jan 2003

Genetic Variation In Black Bears In Arkansas And Louisiana Using Microsatellite Dna Markers, Ildiki Csiki, Cynthia Lam, Audie Key, Erica Coulter, Joseph D. Clark, Richard M. Pace Iii, Kimberley G. Smith, Douglas D. Rhoads

United States Geological Survey: Staff Publications

In the 1950s and 1960s, translocation projects reintroduced black bears (Ursus americanus) from Minnesota and Manitoba to Arkansas and Louisiana. Today, several geographically disconnected populations exist in Arkansas and Louisiana, but their origins are unclear. Some populations may represent a separate subspecies, U. a. luteolus, which is federally protected. We characterized 5 microsatellite loci in 5 isolated populations in Arkansas and Louisiana and compared them with genotypes from Minnesota. Our data indicate that bears of the Ozark and Ouachita mountains of Arkansas, an inland area of Louisiana, and those of Minnesota are similar in overall genetic diversity …

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Evidence For Disease-Related Amphibian Decline In Colorado, Erin Muths, Paul Stephen Corn, Allan P. Pessier, D. Earl Green Jan 2003

Evidence For Disease-Related Amphibian Decline In Colorado, Erin Muths, Paul Stephen Corn, Allan P. Pessier, D. Earl Green

United States Geological Survey: Staff Publications

The recent discovery of a pathogenic fungus (Batrachochytrium dendrobatidis) associated with declines of frogs in the American and Australian tropics, suggests that at least the proximate cause, may be known for many previously unexplained amphibian declines. We have monitored boreal toads in Colorado since 1991 at four sites using capture–recapture of adults and counts of egg masses to examine the dynamics of this metapopulation. Numbers of male toads declined in 1996 and 1999 with annual survival rate averaging 78% from 1991 to 1994, 45% in 1995 and 3% between 1998 and 1999. Numbers of egg masses also declined. …

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Mapping Vegetation In Yellowstone National Park Using Spectral Feature Analysis Of Aviris Data, Raymond F. Kokaly, Don G. Despain, Roger N. Clark, K. Eric Livo Jan 2003

Mapping Vegetation In Yellowstone National Park Using Spectral Feature Analysis Of Aviris Data, Raymond F. Kokaly, Don G. Despain, Roger N. Clark, K. Eric Livo

United States Geological Survey: Staff Publications

Knowledge of the distribution of vegetation on the landscape can be used to investigate ecosystem functioning. The sizes and movements of animal populations can be linked to resources provided by different plant species. This paper demonstrates the application of imaging spectroscopy to the study of vegetation in Yellowstone National Park (Yellowstone) using spectral feature analysis of data from the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS). AVIRIS data, acquired on August 7, 1996, were calibrated to surface reflectance using a radiative transfer model and field reflectance measurements of a ground calibration site. A spectral library of canopy reflectance signatures was created by …

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Paleolimnology Of Lake Tanganyika, East Africa, Over The Past 100 K Yr, Christopher A. Scholz, John W. King, Geoffrey S. Ellis, Peter K. Swart, J. Curt Stager, Steven M. Colman Jan 2003

Paleolimnology Of Lake Tanganyika, East Africa, Over The Past 100 K Yr, Christopher A. Scholz, John W. King, Geoffrey S. Ellis, Peter K. Swart, J. Curt Stager, Steven M. Colman

United States Geological Survey: Staff Publications

New sediment core data from a unique slow-sedimentation rate site in Lake Tanganyika contain a much longer and continuous record of limnological response to climate change than have been previously observed in equatorial regions of central Africa. The new core site was first located through an extensive seismic reflection survey over the Kavala Island Ridge (KIR), a sedimented basement high that separates the Kigoma and Kalemie Basins in Lake Tanganyika.

Proxy analyses of paleoclimate response carried out on core T97-52V include paleomagnetic and index properties, TOC and isotopic analyses of organic carbon, and diatom and biogenic silica analyses. A robust …

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Mississippi River Blufflands And Bird Conservation, Eileen M. Kirsch Jan 2003

Mississippi River Blufflands And Bird Conservation, Eileen M. Kirsch

United States Geological Survey: Staff Publications

The "rubber hits the road" in conservation when the landowning public involved. Researchers and amateur birders know that populations of many species of neotropical migrant birds are declining because of habitat loss and many natural- and human-caused dangers. However, the landowners may not know what neotropical migrants are or that they are in peril. This excellent booklet and enclosed pamphlet are intended to educate landowners along the Mississippi River blufflands in Iowa, Illinois, Wisconsin, and Minnesota about neotropical migrant birds and their plight. Furthermore, it tactfully attempts to inspire concern about neotropical migrants and explains how management can help. While …

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Lake Sediments Record Large-Scale Shifts In Moisture Regimes Across The Northern Prairies Of North America During The Past Two Millennia, Kathleen R. Laird, Brian F. Cumming, Sybille Wunsam, James A. Rusak, Robert J. Oglesby, Sherilyn C. Fritz, Peter R. Leavitt Jan 2003

Lake Sediments Record Large-Scale Shifts In Moisture Regimes Across The Northern Prairies Of North America During The Past Two Millennia, Kathleen R. Laird, Brian F. Cumming, Sybille Wunsam, James A. Rusak, Robert J. Oglesby, Sherilyn C. Fritz, Peter R. Leavitt

Department of Earth and Atmospheric Sciences: Faculty Publications

Six high-resolution climatic reconstructions, based on diatom analyses from lake sediment cores from the northern prairies of North America, show that shifts in drought conditions on decadal through multicentennial scales have prevailed in this region for at least the last two millennia. The predominant broad-scale pattern seen at all sites is a major shift in moisture regimes from wet to dry, or vice versa (depending on location), that occurred after a period of relative stability. These large-scale shifts at the different sites exhibit spatial coherence at regional scales. The three Canadian sites record this abrupt shift between anno Domini 500 …

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Phosphorus Contamination And Storage In Bottom Sediments Of The James River Arm Of Table Rock Lake, Southwest Missouri, Marc R. Owen Jan 2003

Phosphorus Contamination And Storage In Bottom Sediments Of The James River Arm Of Table Rock Lake, Southwest Missouri, Marc R. Owen

Graduate Theses/Dissertations

Eutrophic conditions in the upper James River Arm (JRA) of Table Rock Lake have been linked to phosphorus (P) inputs by wastewater treatment facilities and increasing urban development in the upper James River Basin (3,770 km2). Since the majority of P in aquatic environments is bound to sediments, bottom sediment can function as both a source and sink of P in lake systems. This study evaluates the spatial distribution, physical and chemical characteristics, and storage of sediment-P in the active layer ( < 5cm) of bottom sediments in the JRA. The JRA makes up about 20% of Table Rock Lake’s surface area, contributes about 30% of the inflow, and has the poorest water quality of the entire lake. For this study, grab samples were collected in the main arm and tributary coves at the deepest part of the lake and at several shallow sites along the main arm. Concentrations increase in a down-lake direction in the main arm ranging from 5 to >2000 ppm P. However, water-column P concentrations show a decrease down-lake, indicating that sedimentation is removing P from …

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Temporal Analysis Of Floodplain Deposition Using Urban Pollution Stratigraphy, Wilson Creek, Sw Missouri, Kathy A. Shade Jan 2003

Temporal Analysis Of Floodplain Deposition Using Urban Pollution Stratigraphy, Wilson Creek, Sw Missouri, Kathy A. Shade

Graduate Theses/Dissertations

Alluvial sediments record both hydrologic changes and variations of sediment quality affecting watersheds. This study uses urban pollution signatures as temporal tracers to date alluvial deposits along Wilson Creek located within Wilson’s Creek National Battlefield Park in southwestern Missouri. The creek drains Springfield, the third largest city in the state, which was settled in 1833. This study has three main objectives: (1) review historical documents to develop a pollution history for the watershed; (2) determine if there is a correlation between heavy metal and phosphorus concentrations in sediment cores and the timing of release of those elements into the creek …

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Channel Geomorphology And Restoration Guidelines For Springfield Plateau Streams, South Dry Sac Watershed, Southwest Missouri, John M. Horton Jan 2003

Channel Geomorphology And Restoration Guidelines For Springfield Plateau Streams, South Dry Sac Watershed, Southwest Missouri, John M. Horton

Graduate Theses/Dissertations

Land-use change, both historical and present, has been a source of channel degradation within Ozark streams. This study examines the influence of land use on channel morphology within the South Dry Sac Watershed which drains 78.5 km2. The main objectives of this study are to: (1) perform a geomorphic assessment of stream channel and sediment characteristics; (2) evaluate the effects of watershed factors on channel morphology and dynamics; (3) quantify the geomorphic relationships for use in stream restoration projects in the Springfield Plateau area. Thirty-six reaches were surveyed and evaluated in the field for channel cross-sectional geometry, longitudinal profile, and …

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Weathering Of Sulfidic Shale And Copper Mine Waste: Secondary Minerals And Metal Cycling In Great Smoky Mountains National Park, Tennessee, And North Carolina, Usa, Jane M. Hammarstrom, Robert R. Seal Ii, Allen L. Meier, John C. Jackson Jan 2003

Weathering Of Sulfidic Shale And Copper Mine Waste: Secondary Minerals And Metal Cycling In Great Smoky Mountains National Park, Tennessee, And North Carolina, Usa, Jane M. Hammarstrom, Robert R. Seal Ii, Allen L. Meier, John C. Jackson

United States Geological Survey: Staff Publications

Metal cycling via physical and chemical weathering of discrete sources (copper mines) and regional (non-point) sources (sulfide-rich shale) is evaluated by examining the mineralogy and chemistry of weathering products in Great Smoky Mountains National Park, Tennessee, and North Carolina, USA. The elements in copper mine waste, secondary minerals, stream sediments, and waters that are most likely to have negative impacts on aquatic ecosystems are aluminum, copper, zinc, and arsenic because these elements locally exceed toxicity guidelines for surface waters or for stream sediments. Acid-mine drainage has not developed in streams draining inactive copper mines. Acid-rock drainage and chemical weathering processes …

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Acoustic Mapping Of Aquatic Vegetation In Lakes: An Example From Northwest Arkansas, Angela M. Polly, Stephen K. Boss Jan 2003

Acoustic Mapping Of Aquatic Vegetation In Lakes: An Example From Northwest Arkansas, Angela M. Polly, Stephen K. Boss

Journal of the Arkansas Academy of Science

No abstract provided.

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The Role Of Physical, Chemical, And Microbial Heterogeneity On The Field-Scale Transport And Attachment Of Bacteria, Brian J. Mailloux, Mark E. Fuller, Tullis C. Onstott, James Hall, Hailiang Dong, Mary F. Deflaun, Sheryl H. Streger, Randi K. Rothmel, Maria Green, Donald J. P. Swift, Jon Radke Jan 2003

The Role Of Physical, Chemical, And Microbial Heterogeneity On The Field-Scale Transport And Attachment Of Bacteria, Brian J. Mailloux, Mark E. Fuller, Tullis C. Onstott, James Hall, Hailiang Dong, Mary F. Deflaun, Sheryl H. Streger, Randi K. Rothmel, Maria Green, Donald J. P. Swift, Jon Radke

OES Faculty Publications

A field-scale bacterial transport experiment was conducted at the Narrow Channel Focus Area of the South Oyster field site located in Oyster, Virginia. The goal of the field experiment was to determine the relative influence of subsurface heterogeneity and microbial population parameters on flow direction, velocity, and attachment of bacteria at the field scale. The field results were compared with results from laboratory-scale column experiments to develop a method for predicting field-scale bacterial transport. The field site is a shallow, sandy, unconfined, aerobic aquifer that has been characterized by geophysical, sedimentological, and hydrogeological methods. Comamonas sp. strain DA001 and a …

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New Evidence For Enhanced Ocean Primary Production Triggered By Tropical Cyclone, I. Lin, W. Timothy Liu, Chun-Chieh Wu, George T. F. Wong, Chuanmin Hu, Zhiqiang Chen, Wen-Der Liang, Yih Yang, Kon-Kee Liu Jan 2003

New Evidence For Enhanced Ocean Primary Production Triggered By Tropical Cyclone, I. Lin, W. Timothy Liu, Chun-Chieh Wu, George T. F. Wong, Chuanmin Hu, Zhiqiang Chen, Wen-Der Liang, Yih Yang, Kon-Kee Liu

OES Faculty Publications

[1] New evidence based on recent satellite data is presented to provide a rare opportunity in quantifying the long-speculated contribution of tropical cyclones to enhance ocean primary production. In July 2000, moderate cyclone Kai-Tak passed over the South China Sea (SCS). During its short 3-day stay, Kai-Tak triggered an average 30-fold increase in surface chlorophyll-a concentration. The estimated carbon fixation resulting from this event alone is 0.8 Mt, or 2-4% of SCS's annual new production. Given an average of 14 cyclones passing over the SCS annually, we suggest the long-neglected contribution of tropical cyclones to SCS's annual new production may …

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Snow-Patch Influence On Soil Biogeochemical Processes And Invertebrate Distribution In The Mcmurdo Dry Valleys, Antarctica, Michael N. Gooseff, John E. Barrett, Peter T. Doran, Andrew G. Fountain, W. Berry Lyons, Andrew N. Parsons, Dorota L. Porazinska, Ross A. Virginia, Diana H. Wall Jan 2003

Snow-Patch Influence On Soil Biogeochemical Processes And Invertebrate Distribution In The Mcmurdo Dry Valleys, Antarctica, Michael N. Gooseff, John E. Barrett, Peter T. Doran, Andrew G. Fountain, W. Berry Lyons, Andrew N. Parsons, Dorota L. Porazinska, Ross A. Virginia, Diana H. Wall

Geography Faculty Publications and Presentations

The McMurdo Dry Valleys is the largest of the ice-free areas in Antarctica. Precipitation events in excess of 1 cm of snow accumulation are rare. During the winter, snow is transported by strong katabatic winds blowing from the polar plateau, and deposited into the lee of topographic features (e.g., stream channels and other topographic depressions). At the start of the austral summer (early October), as much as 10% of the valley soils may be covered by distributed snow patches. Because liquid water is the primary driver of biological, physical, and chemical processes in this polar desert, quantifying fluxes of water …

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Assessing The Paleoclimatic Utility Of The Indo-Pacific Coral Genus Diploastrea In A 225-Year Oxygen Isotope Record From Fiji, Stefan Bagnato Jan 2003

Assessing The Paleoclimatic Utility Of The Indo-Pacific Coral Genus Diploastrea In A 225-Year Oxygen Isotope Record From Fiji, Stefan Bagnato

Geology Theses and Dissertations

In the Western Pacific there remains, both spatially and temporally, a sparse record of surface ocean conditions and very few long paleoclimate records able to extend our understanding of this important region. The coral genus Porites is the common coral currently used for Pacific paleoclimate studies and has proven to be very useful. The massive coral Diploastrea, due to its slow growth rate and dense structure, may preserve temporally longer geochemical proxy records than Porites colonies of the same length. Its long lifespan and fossil history give this genus great potential; however no assessment has been made of the paleoclimatic …

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Sediment-Water Interactions Affecting Dissolved-Mercury Distributions In Camp Far West Reservoir, California, James S. Kuwabara, Charles N. Alpers, Mark Marvin-Dipasquale, Brent R. Topping, James L. Carter, A. Robin Stewart, Steven V. Fend, Francis Parchaso, Gerald E. Moon, David P. Krabbenhoft Jan 2003

Sediment-Water Interactions Affecting Dissolved-Mercury Distributions In Camp Far West Reservoir, California, James S. Kuwabara, Charles N. Alpers, Mark Marvin-Dipasquale, Brent R. Topping, James L. Carter, A. Robin Stewart, Steven V. Fend, Francis Parchaso, Gerald E. Moon, David P. Krabbenhoft

United States Geological Survey: Publications

Field and laboratory studies were conducted in April and November 2002 to provide the first direct measurements of the benthic flux of dissolved (0.2-micrometer filtered) mercury species (total and methylated forms) between the bottom sediment and water column at three sampling locations within Camp Far West Reservoir, California: one near the Bear River inlet to the reservoir, a second at a mid-reservoir site of comparable depth to the inlet site, and the third at the deepest position in the reservoir near the dam (herein referred to as the inlet, midreservoir and near-dam sites, respectively; Background, Fig. 1). Because of interest …

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Seasonal Distribution Of Migratory Tree Bats (Lasiurus And Lasionycteris) In North America, Paul M. Cryan Jan 2003

Seasonal Distribution Of Migratory Tree Bats (Lasiurus And Lasionycteris) In North America, Paul M. Cryan

United States Geological Survey: Staff Publications

Despite evidence of migration in North American tree bats (genera Lasiurus and Lasionycteris), details regarding seasonal movements in these widely distributed species are few. This study attempted to clarify patterns of seasonal distribution by mapping museum occurrence records by month. Monthly changes in the distribution of records indicate seasonal movements of tree bats. Northward migration during spring by Lasiurus cinereus appears to stem from wintering grounds in California and Mexico. During summer, male L. cinereus is mainly distributed in western North America, whereas females dominate samples from eastern regions. Lasiurus borealis winters in southeastern areas and expands its range …

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Last Glacial Loess In The Conterminous Usa, E. Arthur Bettis Iii, Daniel R. Muhs, Helen M. Roberts, Ann G. Wintle Jan 2003

Last Glacial Loess In The Conterminous Usa, E. Arthur Bettis Iii, Daniel R. Muhs, Helen M. Roberts, Ann G. Wintle

United States Geological Survey: Staff Publications

The conterminous United States contains an extensive and generally well-studied record of Last Glacial loess. The loess occurs in diverse physiographic provinces, and under a wide range of climatic and ecological conditions. Both glacial and non-glacial loess sources are present, and many properties of the loess vary systematically with distance from loess sources. United States’ mid-continent Last Glacial loess is probably the thickest in the world, and our calculated mass accumulation rates (MARs) are as high as 17,500 g/m2/yr at the Bignell Hill locality in Nebraska, and many near-source localities have MARs greater than 1500 g/m2/yr. …

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