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Patterns Of Total Suspended Solids Concentration And The Influence Of Antecedent Conditions On Hydrograph Response To Precipitation Events On Beaver Creek, Ontario, Matthew Peter Roy Mittler Jan 2006

Patterns Of Total Suspended Solids Concentration And The Influence Of Antecedent Conditions On Hydrograph Response To Precipitation Events On Beaver Creek, Ontario, Matthew Peter Roy Mittler

Theses and Dissertations (Comprehensive)

This study explored relationships between suspended solids concentration and discharge, the influence of antecedent conditions on event hydrograhs and the state of dynamic equilibrium in a second-order stream (Beaver Creek), draining an agricultural basin in southern Ontario, near the City of Waterloo. Beaver creek was monitored for nineteen weeks from July to November of 2005. Thirteen precipitation events of various magnitude and duration were examined within the study period. Discharge and total suspended soils were sampled throughout the events. Cross sectional profiles of six transects were measured prior to and after each event. Base flow, antecedent conditions and event response …


Service-Learning In Watershed-Based Initiatives: Keys To Education For Sustainability In Geography?, James Eflin, Amy L. Sheaffer Jan 2006

Service-Learning In Watershed-Based Initiatives: Keys To Education For Sustainability In Geography?, James Eflin, Amy L. Sheaffer

Service Learning, General

A call for combining the strengths of geographic education with environmental education to produce an 'education for sustainability' addresses local problems for sustainable development. A place-based approach encourages civic responsibility among students. Using service-learning to extend education beyond the classroom in this case study connected students with local clients in a watershed-based initiative. Theoretical underpinnings of service-learning for geographic education are discussed, and the case study is viewed from instructor, student, and client perspectives to identify successful outcomes and provide suggestions for those who might adopt service-learning for the first time.


Phosphorus Sorption In Relation To Soil Grain Size And Geochemical Composition In The Simiyu And Kagera River Basins, Tanzania, R. A. Tamatamah Dec 2005

Phosphorus Sorption In Relation To Soil Grain Size And Geochemical Composition In The Simiyu And Kagera River Basins, Tanzania, R. A. Tamatamah

Tanzania Journal of Science

The phosphorus sorption characteristics of eight surface soil samples representative of the land use and landscape in the Simiyu and Kagera River basins were determined using the Langmuir equation. The Langmuir P adsorption maximum (Cmax) ranged from 109 to 802 mg kg-1, while Langmuir coefficient (K) ranged from 59 to 736 mg L-1. Cmax and were positively correlated to clay content, aluminium (Al), and iron (Fe) and negatively correlated to calcium (Ca). By using stepwise regression, the combination of Al, Fe, clay and Ca predicted more than 94% of the variation in the P sorption capacity of soils samples from …


Observations Of Sand Waves, Megaripples, And Hummocks In The Dutch Coastal Area And Their Relation To Currents And Combined Flow Conditions, Sandra Passchier, Maarten Kleinhans Dec 2005

Observations Of Sand Waves, Megaripples, And Hummocks In The Dutch Coastal Area And Their Relation To Currents And Combined Flow Conditions, Sandra Passchier, Maarten Kleinhans

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

[1] This paper aims to investigate the distribution and stability of large‐scale bed forms in response to storm and fair‐weather conditions in a shallow marine environment. Multibeam and side‐scan sonar data off the Dutch coast (median grain size 0.25–0.35 mm) were collected to monitor sand waves (λ = 100–800 m) and superimposed megaripples (λ = 1–40 m) through multiple storm and fair‐weather events. Box cores were used to observe the vertical bed structure and grain size. In the Dutch coastal area, two‐dimensional (2‐D) megaripples (λ = 1–15 m) are the dominant bed forms in current‐dominated (>0.4 m/s) tidal flow …


Carbon Isotope Of Bulk Organic Matter: A Proxy For Precipitation In The Arid And Semiarid Central East Asia, Xinqing Lee, Zhaodong Feng, Lanlan Guo, Lixia Wang, Liya Jin, Yongsong Huang, Mark Chopping, Daikuan Huang, Wei Jiang, Qian Jiang, Hongguang Cheng Dec 2005

Carbon Isotope Of Bulk Organic Matter: A Proxy For Precipitation In The Arid And Semiarid Central East Asia, Xinqing Lee, Zhaodong Feng, Lanlan Guo, Lixia Wang, Liya Jin, Yongsong Huang, Mark Chopping, Daikuan Huang, Wei Jiang, Qian Jiang, Hongguang Cheng

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Carbon isotope composition (δ13C) of bulk organic matter in soil and lake sediment sequences has been widely used to infer past climate changes. The specific climatic representation of the isotopic signature, however, lacks for examination. With excellent gradients of temperature and precipitation, as well as the gradients of vegetation zone, central East Asia provides an ideal background for developing the relationship between the δ13C and the climatic parameters. Analysis of surface soil organic matter from a transect that crosses the various climatic and vegetation zones reveals a significant linear correlation between δ13C and the mean precipitation from May to September …


Quantifying Atmospheric Nitrogen Deposition As A Nonpoint Source Pollution And Its Potential Effects On The Mullica River-Great Bay Ecosystem, Jennifer Haag May 2005

Quantifying Atmospheric Nitrogen Deposition As A Nonpoint Source Pollution And Its Potential Effects On The Mullica River-Great Bay Ecosystem, Jennifer Haag

Theses, Dissertations and Culminating Projects

To characterize atmospheric nitrogen deposition and its potential impact on the Mullica River-Great Bay Estuary, atmospheric sampling was conducted at Rutgers University Marine Field Station in Tuckerton, New Jersey from March 2004 to March 2005. A total of 52 precipitation samples were collected on an event basis using a MIC wet-only automatic precipitation sampler. A total of 23 aerosol samples were also taken during this period of time with a high-volume aerosol sampler. Chemical analysis was performed using a Dionex Ion Chromatograph to determine the concentrations of nitrate and ammonium in precipitation and associated with aerosols. Nitrate concentrations for precipitation …


Short-Term And Long-Term Effects Of High Intensity Forest Fires On Soil Phyllosilicates, Jennifer Rose Reynard May 2005

Short-Term And Long-Term Effects Of High Intensity Forest Fires On Soil Phyllosilicates, Jennifer Rose Reynard

Theses, Dissertations and Culminating Projects

High intensity forest fires can alter the clay minerals found in soils. These minerals can be degraded, collapsed, as well as completely destroyed. Signatures of these fires may remain for years after the bums. To ascertain the impact of high intensity fire on soil physical properties, samples were collected from the area in and around the 2002 Hayman, Colorado, fire. These included burned samples from several areas within the perimeter of the fire (taken one to four months following the fire), unburned samples near the origin of the fire, as well as samples from areas of historic burns nearby. This …


Environmental Restoration : The Catalyst Of A City's Successful Revitalization, A Potential Application Example, City Of Camden, New Jersey, Maria Del Rocio Bosch Clark May 2005

Environmental Restoration : The Catalyst Of A City's Successful Revitalization, A Potential Application Example, City Of Camden, New Jersey, Maria Del Rocio Bosch Clark

Theses, Dissertations and Culminating Projects

This thesis aims to concisely emphasize and demonstrate the importance of the connection between urban and natural environments, towards fostering a strong and healthy quality of life for its citizens.

The notion of applying an integrated comprehensive approach to city planning and environmental restoration (such as brownfields redevelopment) is lacking throughout many communities. On the other hand, "success stories" exist around the world that link a comprehensive city plan and environmental restoration to their successes. These attestations of accomplishments demonstrate that regardless of the geographical or economic circumstances, this thesis concept might be applied.

This thesis concept is simplified by …


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. …


Morphology Of Methane Hydrate Host Sediments, Keith W. Jones, Huan Feng, Stanmire Tomov, William J. Winters, Michael Eaton, Devinder Mahajan Feb 2005

Morphology Of Methane Hydrate Host Sediments, Keith W. Jones, Huan Feng, Stanmire Tomov, William J. Winters, Michael Eaton, Devinder Mahajan

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The morphological features including porosity and grains of methane hydrate host sediments were investigated using synchrotron computed microtomography (CMT) technique. The sediment sample was obtained during Ocean Drilling Program Leg 164 on the Blake Ridge at water depth of 2278.5 m. The CMT experiment was performed at the Brookhaven National Synchrotron Light Source facility. The analysis gave ample porosity, specific surface area, mean particle size, and tortuosity. The method was found to be highly effective for the study of methane hydrate host sediments.


Evolution Of The Magmatic-Hydrothermal Acid-Sulfate System At Summitville, Colorado: Integration Of Geological, Stable-Isotope, And Fluid-Inclusion Evidence, Philip M. Bethke, Robert O. Rye, Roger E. Stoffregen, Peter G. Vikre Jan 2005

Evolution Of The Magmatic-Hydrothermal Acid-Sulfate System At Summitville, Colorado: Integration Of Geological, Stable-Isotope, And Fluid-Inclusion Evidence, Philip M. Bethke, Robert O. Rye, Roger E. Stoffregen, Peter G. Vikre

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

The Summitville Au–Ag–Cu deposit is a classic volcanic dome-hosted high-sulfidation deposit. It occurs in the Quartz Latite of South Mountain, a composite volcanic dome that was emplaced along the coincident margins of the Platoro and Summitville calderas at 22.5±0.5 Ma, penecontemporaneous with alteration and mineralization. A penecontemporaneous quartz monzonite porphyry intrusion underlies the district and is cut and overlain by pyrite–quartz stockwork veins with traces of chalcopyrite and molybdenite. Alteration and mineralization proceeded through three hypogene stages and a supergene stage, punctuated by at least three periods of hydrothermal brecciation. Intense acid leaching along fractures in the quartz latite produced …


Supergene Destruction Of A Hydrothermal Replacement Alunite Deposit At Big Rock Candy Mountain, Utah: Mineralogy, Spectroscopic Remote Sensing, Stable-Isotope, And Argon-Age Evidences, Charles G. Cunningham, Robert O. Rye, Barnaby W. Rockwell, Michael J. Kunk, Terry B. Councell Jan 2005

Supergene Destruction Of A Hydrothermal Replacement Alunite Deposit At Big Rock Candy Mountain, Utah: Mineralogy, Spectroscopic Remote Sensing, Stable-Isotope, And Argon-Age Evidences, Charles G. Cunningham, Robert O. Rye, Barnaby W. Rockwell, Michael J. Kunk, Terry B. Councell

Geochemistry of Sulfate Minerals: A Tribute to Robert O. Rye

Big Rock Candy Mountain is a prominent center of variegated altered volcanic rocks in west-central Utah. It consists of the eroded remnants of a hypogene alunite deposit that, at ~21 Ma, replaced intermediate-composition lava flows. The alunite formed in steam-heated conditions above the upwelling limb of a convection cell that was one of at least six spaced at 3- to 4- km intervals around the margin of a monzonite stock. Big Rock Candy Mountain is horizontally zoned outward from an alunite core to respective kaolinite, dickite, and propylite envelopes. The altered rocks are also vertically zoned from a lower pyrite– …


Unruly Complexity: Ecology, Interpretation, Engagement, Peter Taylor Jan 2005

Unruly Complexity: Ecology, Interpretation, Engagement, Peter Taylor

Curriculum and Instruction Faculty Publication Series

Ambitiously identifying fresh issues in the study of complex systems, Peter J. Taylor, in a model of interdisciplinary exploration, makes these concerns accessible to scholars in the fields of ecology, environmental science, and science studies. Unruly Complexity explores concepts used to deal with complexity in three realms: ecology and socio-environmental change; the collective constitution of knowledge; and the interpretations of science as they influence subsequent research.

For each realm Taylor shows that unruly complexity-situations that lack definite boundaries, where what goes on "outside" continually restructures what is "inside," and where diverse processes come together to produce change-should not be suppressed …


New Standards For Reducing Gravity Data: The North American Gravity Database, William J. Hinze, Carlos Aiken, John Brozena, Bernard Coakley, David Dater, Guy Flanagan, Rene Forsberg, Thomas Hildenbrand, G. Randy Keller, James N. Kellogg, Robert Kucks, Xiong Li, Andre Mainville, Robert Morin, Mark Pilkington, Donald Plouff, Dhananjay Ravat, Daniel Roman, Jamie Urrutia-Fucugauchi, Marc Veronneau, Michael Webring, Daniel Winester Jan 2005

New Standards For Reducing Gravity Data: The North American Gravity Database, William J. Hinze, Carlos Aiken, John Brozena, Bernard Coakley, David Dater, Guy Flanagan, Rene Forsberg, Thomas Hildenbrand, G. Randy Keller, James N. Kellogg, Robert Kucks, Xiong Li, Andre Mainville, Robert Morin, Mark Pilkington, Donald Plouff, Dhananjay Ravat, Daniel Roman, Jamie Urrutia-Fucugauchi, Marc Veronneau, Michael Webring, Daniel Winester

Faculty Publications

The North American gravity database as well as databases from Canada, Mexico, and the United States are being revised to improve their coverage, versatility, and accuracy. An important part of this effort is revising procedures for calculating gravity anomalies, taking into account our enhanced computational power, improved terrain databases and datums, and increased interest in more accurately defining long-wavelength anomaly components. Users of the databases may note minor differences between previous and revised database values as a result of these procedures. Generally, the differences do not impact the interpretation of local anomalies but do improve regional anomaly studies. The most …


Chemical Analyses In Support Of Yucca Mountain Studies, Jeanette Daniels, Klaus J. Stetzenbach, Drew Coleman, Amy J. Smiecinski, Raymond E. Keeler Dec 2004

Chemical Analyses In Support Of Yucca Mountain Studies, Jeanette Daniels, Klaus J. Stetzenbach, Drew Coleman, Amy J. Smiecinski, Raymond E. Keeler

Publications (YM)

The objective of this task “Chemical Analyses in Support of Yucca Mountain Studies” is to provide the Department of Energy (DOE) with data and reports from comprehensive chemical analyses of waters sampled from the wells of the Nye County Early Warning Drilling Program (NCEWDP), the Inyo County’s Drilling Program, and the Nye county Tracer Test. In addition, this task will be used to provide other laboratory support needs as they arise within the Yucca Mountain Project. This support is provided by the Harry Reid Center for Environmental Studies (HRC) at University of Nevada, Las Vegas (UNLV), which is part of …


Long-Term Mechanical Behavior Of Yucca Mountain Tuffs, And Its Variability, Jaak J.K. Daemen, George Danko, Jaime Gonzalez, Amy J. Smiecinski, Raymond E. Keeler Oct 2004

Long-Term Mechanical Behavior Of Yucca Mountain Tuffs, And Its Variability, Jaak J.K. Daemen, George Danko, Jaime Gonzalez, Amy J. Smiecinski, Raymond E. Keeler

Publications (YM)

We propose to continue the investigation of the long term strength of Yucca Mountain tuffs, with particular emphasis on tuffs from and near the emplacement horizon. We propose to also continue and expand the investigation of the spatial variability of rock strength and stiffness. An intrinsic component of this planned rock testing is the testing of rock joints. Although the emphasis is on tests aimed at determining long term strength, as part of the testing measurements of stiffness also are collected, and will be collected, reported, and analyzed.


Accuracy Of Neural Network Classifiers In Humid Tropical Areas, Genong Yu Aug 2004

Accuracy Of Neural Network Classifiers In Humid Tropical Areas, Genong Yu

All-Inclusive List of Electronic Theses and Dissertations

This research develops a better understanding of the use of neural networks in the context of tropical land cover characterization using multiple scale remotely sensed data. Results of the research contributed to developing a robust neural network classifier suitable to use for humid tropical land cover classification in areas such as Altamira, Brazil. Research was focused upon the following: (1) performance ofneural networks with different ancillary data- such as DEM (digital elevation model) and its derivatives; (2) effect of spatial scale on neural network classifiers using remote sensing data from IKONOS, Landsat TM, ASTER, and MODIS; (3) accuracy of neural …


Experimental Investigation Of Time Dependent Behavior Of Welded Topopah Spring Tuff, Lumin Ma Aug 2004

Experimental Investigation Of Time Dependent Behavior Of Welded Topopah Spring Tuff, Lumin Ma

Publications (YM)

Four types of laboratory tests have been performed. Specimens were attained from four lithophysal zones of the welded Topopah Spring Tuff unit at Yucca Mountain, Nevada: upper lithophysal, middle nonlithophysal, lower lithophysal and lower nonlithophysal zones. Two types of tests are conducted to study time-dependent behavior: constant strain rate and creep tests. Sixty five specimens from the middle nonlithophysal zone were tested at six strain rates: 10 , 10 , 10 , 10 , 10 , and 10 . Test durations range from 2 seconds to 7 days. Fourteen specimens from middle nonlithophysal, lower lithophysal and lower nonlithophysal zones are …


Anthropogenic Lead Deposition And Four National Parks In Poland As Determined By Lead Isotope Ratios, Shannon Simcoe Jul 2004

Anthropogenic Lead Deposition And Four National Parks In Poland As Determined By Lead Isotope Ratios, Shannon Simcoe

OES Theses and Dissertations

Polluted soils are recognized by having high concentrations of heavy metals, including Pb. Partitioning of metals in geochemical fractions, by sequential chemical extractions, may indicate whether a metal has been recently deposited in the soil. While concentration levels alone cannot distinguish between natural and anthropogenic Pb, studies have demonstrated that anthropogenic pollution is accurately recorded by specific Pb isotope signatures, which differ from natural Pb isotopes. The objective of this project was to use 206Pb/207Pb and 206Pb/204Pb isotope ratios to differentiate between the anthropogenic Pb input and the naturally occurring Pb in four national …


Chemical Analyses For Alcove 8/Niche 3 Tracer Studies, Jeanette Daniels, Klaus J. Stetzenbach, Drew Coleman, Don Baepler, Amy J. Smiecinski May 2004

Chemical Analyses For Alcove 8/Niche 3 Tracer Studies, Jeanette Daniels, Klaus J. Stetzenbach, Drew Coleman, Don Baepler, Amy J. Smiecinski

Publications (YM)

The objective of this task “Analytical Support For Tracer Studies in Alcove 8 / Niche 3” is to provide chemical analyses for the tracer studies at Alcove 8 / Niche 3 in the Exploratory Studies Facilities (ESF). This analytical support includes developing procedures for measuring tracer concentrations and then performing the tracer (and other background constituent) analyses for the water samples generated from each Alcove 8 / Niche 3 tracer test. These tracer tests are part of the Flow and Seepage Testing in Alcove 8/Niche 3 (TWP-NBS-HS-000004 REV 00). The overall goal of this study is to quantify large scale …


Defining Archaeological Stratigraphy: Evaluating Microartifact Sampling, David N. Holycross May 2004

Defining Archaeological Stratigraphy: Evaluating Microartifact Sampling, David N. Holycross

All-Inclusive List of Electronic Theses and Dissertations

A variety of subsurface methods have been used to discover and evaluate buried archaeological occupations. Researchers such as Stafford (1993,1995) have proposed that micro artifacts are an effective means of defining the archaeological stratigraphy of deposits, but only limited evaluation of this approach has been undertaken. This study tested the utility of microartifacts within a range of sample size and site density characteristics at three Ohio Valley archaeological sites buried within early and late Holocene age landforms. Occupations were typically detected in unit-to-core comparisons, within acceptable margins of error, and microartifacts often revealed a more complex stratigraphy than reflected by …


Ground Water Level Measurements In Selected Boreholes Near The Site Of The Proposed Repository, H. Scott Page, Klaus J. Stetzenbach, Drew Coleman, Don Baepler, Amy J. Smiecinski Mar 2004

Ground Water Level Measurements In Selected Boreholes Near The Site Of The Proposed Repository, H. Scott Page, Klaus J. Stetzenbach, Drew Coleman, Don Baepler, Amy J. Smiecinski

Publications (YM)

The objective of this task is to provide ground water level measurements of known accuracy and precision using manual and electronic methods. The HRC will use field-proven protocols and established implementing procedures for all aspects of data collection, analysis, management, and reporting. The water level measurements produced by this program will yield quality-assured data that can be reliably used for a variety of purposes including: continued site characterization, refinement of the local potentiometric surface, inputs to the Death Valley Regional Flow Model and related hydrologic characterization, to fulfill permit conditions issued by the State of Nevada, to monitor seismically-induced ground …


Paleomagnetism And 40ar/39ar Chronology Of Lavas From Meseta Del Lago Buenos Aires, Patagonia, Laurie L. Brown, Brad S. Singer, Matthew L. Gorring Jan 2004

Paleomagnetism And 40ar/39ar Chronology Of Lavas From Meseta Del Lago Buenos Aires, Patagonia, Laurie L. Brown, Brad S. Singer, Matthew L. Gorring

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

[1] As part of a larger project investigating paleosecular variation in South America, 36 paleomagnetic and geochronology sites were sampled on Meseta del Lago Buenos Aires (47°S, 289°E), 200 km east of the active plate boundary in southern Patagonia. Basaltic lavas sampled range from late Miocene to late Pleistocene yet most of the individual lavas are younger than 3.3 Ma. Thirty-eight isochron ages determined via 40Ar/39Ar incremental-heating experiments frame a detailed stratigraphy. The isochron ages range from 66.9 ± 4.1 ka for scoria cones and a youthful lava flow in the Rio Pinturas valley to 10.12 ± 1.35 Ma for …


Application Of Pyrolysis-Gc/Ms For Rapid Assessment Of Organic Contamination In Sediments From Barcelona Harbor, Michael A. Kruge, Albert Permanyer Jan 2004

Application Of Pyrolysis-Gc/Ms For Rapid Assessment Of Organic Contamination In Sediments From Barcelona Harbor, Michael A. Kruge, Albert Permanyer

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Pyrolysis-GC/MS is advantageous as a tool for rapid sediment contamination assessment because of the small sample size required, minimal sample preparation, and its ability to detect a wide variety of organic pollutants as well as naturally-occurring biological materials. Py-GC/MS was applied, together with determination of organic carbon, and major and minor element concentrations, to evaluate potentially contaminated sediments in the port of Barcelona (Spain) and the adjacent Llobregat River delta. Detected contaminant markers, most evident in the Old Port (Port Vell) area, included hopanes and alkylated PAHs (petroleum), sterenes (sewage), C16-C19 phenylalkanes (detergents) and parent …


Mute Swans And Their Chesapeake Bay Habitats:Proceedings Of A Symposium, Matthew C. Perry Jan 2004

Mute Swans And Their Chesapeake Bay Habitats:Proceedings Of A Symposium, Matthew C. Perry

United States Geological Survey: Publications

The symposium “Mute Swans and their Chesapeake Bay Habitats,” held on June 7, 2001, provided a forum for biologists and managers to share research findings and management ideas concerning the exotic and invasive mute swan (Cygnus olor). This species has been increasing in population size and is considered by many to be a problem in regard to natural food resources in the Bay that are used by native waterfowl during the winter months. Other persons, however, feel that resource managers are attempting to create a problem to justify more killing of waterfowl by hunters. Some persons also believe …


Temporal Variability In Nutrient Transport In A First-Order Agricultural Basin In Southern Ontario, Merrin L. Macrae Jan 2004

Temporal Variability In Nutrient Transport In A First-Order Agricultural Basin In Southern Ontario, Merrin L. Macrae

Theses and Dissertations (Comprehensive)

This thesis examines phosphorus and nitrate transport in a first-order agricultural catchment in Southern Ontario. Specific areas of concern relate to (1) long- and short-term temporal variability in nutrient export patterns, (2) the role of drainage tiles in annual nutrient export, (3) the effects of antecedent hydrologic conditions (AHC) on nutrient export patterns and (4) temporal variability in the nutrient retention in riparian buffer strips and streams. Temporal variability in hydrochemical export from the study basin over a two-year period is described and quantified and the importance of high magnitude events is highlighted. This is the first comprehensive study to …


Consequences Of Reservoir Drainage On Downstream Water Chemistry, Suspended Sediment, And Nutrients, Southwest Missouri, Mark W. Bowen Jan 2004

Consequences Of Reservoir Drainage On Downstream Water Chemistry, Suspended Sediment, And Nutrients, Southwest Missouri, Mark W. Bowen

Graduate Theses/Dissertations

Construction and subsequent draining of reservoirs can have dramatic affects on the release of nutrients and sediments to waterways. This study describes how the temporary draining of a small reservoir for dam repair influences downstream water quality. The Valley Mill Reservoir has a surface area of 6.1 hectares and volume of 150,000 m3 when filled. Water chemistry monitoring and water sampling were performed at six sites during baseflow and ten sites during runoff events for one year. Water samples were analyzed for total nitrogen (TN), total phosphorous (TP), and total suspended sediment (TSS) concentrations. Results indicate that draining of Valley …


Radiocarbon Date List X: Baffin Bay, Baffin Island, Iceland, Labrador Sea, And The Northern North Atlantic, J.T. Andrews, J.P. Briner, D.C. Barber, I.S. Castaneda, T.A. Cooper, G. Dunhill, S. Hagen, M. Hald, F.R. Hall, E. James, A.E. Jennings, N. Koc, G.B Kristjansdottir, Sarah M. Principato, L.M. Smith, T. Vorren, N. Weiner, K. Williams Jan 2004

Radiocarbon Date List X: Baffin Bay, Baffin Island, Iceland, Labrador Sea, And The Northern North Atlantic, J.T. Andrews, J.P. Briner, D.C. Barber, I.S. Castaneda, T.A. Cooper, G. Dunhill, S. Hagen, M. Hald, F.R. Hall, E. James, A.E. Jennings, N. Koc, G.B Kristjansdottir, Sarah M. Principato, L.M. Smith, T. Vorren, N. Weiner, K. Williams

Environmental Studies Faculty Publications

Date List X contains an annotated listing of 213 radiocarbon dates determined on samples from marine and terrestrial environments. The marine samples were collected from the East Greenland, Iceland, Spitzbergen, and Norwegian margins, Baffin Bay, and Labrador Sea. The terrestrial samples were collected from Vestfirdir, Iceland and Baffin Island. The samples were submitted by INSTAAR and researchers affiliated with INSTAAR's Micropaleontology Laboratory under the direction of Dr.’s John T. Andrews and Anne E. Jennings. All of the dates from marine sediment cores were determined from either shells or foraminifera (both benthic and planktic). All dates were obtained by the Accelerator …


Greening Connecticut Cities And Towns, Managing Public Trees And Community Forests, Glenn D. Dreyer, Robert M. Ricard Jan 2004

Greening Connecticut Cities And Towns, Managing Public Trees And Community Forests, Glenn D. Dreyer, Robert M. Ricard

Other Publications and Reports

No abstract provided.


Hydrologic Variation During The Last 170,000 Years In The Southern Hemisphere Tropics Of South America, Sherilyn C. Fritz, Paul A. Baker, Tim K. Lowenstein, Geoffrey O. Seltzer, Catherine A. Rigsby, Gary S. Dwyer, Pedro M. Tapia, Kimberly K. Arnold, Teh-Lung Ku, Shangde Luo Jan 2004

Hydrologic Variation During The Last 170,000 Years In The Southern Hemisphere Tropics Of South America, Sherilyn C. Fritz, Paul A. Baker, Tim K. Lowenstein, Geoffrey O. Seltzer, Catherine A. Rigsby, Gary S. Dwyer, Pedro M. Tapia, Kimberly K. Arnold, Teh-Lung Ku, Shangde Luo

Department of Earth and Atmospheric Sciences: Faculty Publications

Despite the hypothesized importance of the tropics in the global climate system, few tropical paleoclimatic records extend to periods earlier than the last glacial maximum (LGM), about 20,000 years before present. We present a well-dated 170,000-year time series of hydrologic variation from the southern hemisphere tropics of South America that extends from modern times through most of the penultimate glacial period. Alternating mud and salt units in a core from Salar de Uyuni, Bolivia reflect alternations between wet and dry periods. The most striking feature of the sequence is that the duration of paleolakes increased in the late Quaternary. This …