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Articles 151 - 180 of 251

Full-Text Articles in Oceanography and Atmospheric Sciences and Meteorology

Method Analysis Of Laboratory Measures Of Stream Sediment And Water Phosphorus Equilibrium, Anna L. Erickson, Stephanie M. Williamson, Brian E. Haggard Jan 2004

Method Analysis Of Laboratory Measures Of Stream Sediment And Water Phosphorus Equilibrium, Anna L. Erickson, Stephanie M. Williamson, Brian E. Haggard

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Elevated phosphorus concentrations in aquatic ecosystems of northwest Arkansas prompted an investigation of the effects of sample preparation and extraction methods on laboratory measures of sediment-phosphorus interactions. Two streams of contrasting phosphorus (P) concentrations were selected to determine the effect of using a CaCl2 solution instead of filtered stream water, refrigerated or dried sediments instead of fresh wet sediments, and vortexing the suspensions instead of shaking them. Sediment equilibrium P concentration (EPC0) and P buffering capacity (K) were used to determine differences in extraction methods. EPC0 and K from extractions using fresh sediments and a CaCl2 solution matching the electrical …


Swine Waste Demonstration And Training Project, C. V. Maxwell, K. Vandevender, K. P. Coffey, P. A. Moore, I. Chaubey, D. R. Smith Dec 2003

Swine Waste Demonstration And Training Project, C. V. Maxwell, K. Vandevender, K. P. Coffey, P. A. Moore, I. Chaubey, D. R. Smith

Arkansas Water Resources Center Technical Reports

No abstract provided.


Conference Summary: Water, Climate And Uncertainty: Implications For Western Water Law, Policy, And Management, Steve Bailey Jun 2003

Conference Summary: Water, Climate And Uncertainty: Implications For Western Water Law, Policy, And Management, Steve Bailey

Water, Climate and Uncertainty: Implications for Western Water Law, Policy, and Management (Summer Conference, June 11-13)

7 pages.

"Steve Bailey, National Center for Atmospheric Research"


Slides: California Water And Climate Change, Dan Cayan, Mike Dettinger Jun 2003

Slides: California Water And Climate Change, Dan Cayan, Mike Dettinger

Water, Climate and Uncertainty: Implications for Western Water Law, Policy, and Management (Summer Conference, June 11-13)

Presenter: Dan Cayan, Scripps Institution of Oceanography

32 slides

"Dan Cayan (1,2) 1 Mike Dettinger (2,1) SIO 2 USGS 3"


Conference Guidebook: Water, Climate And Uncertainty: An Introduction To The Issues, Language, Literature And The Conference Materials, Doug Kenney Jun 2003

Conference Guidebook: Water, Climate And Uncertainty: An Introduction To The Issues, Language, Literature And The Conference Materials, Doug Kenney

Water, Climate and Uncertainty: Implications for Western Water Law, Policy, and Management (Summer Conference, June 11-13)

20 pages.

"Prepared as a Supplement to: Water, Climate and Uncertainty: Implications for Western Water Law, Policy, and Management, Natural Resources Law Center, University of Colorado School of Law, June 11-13, 2003"

"Doug Kenney, Ph.D."

Includes bibliographical references

Contents:

Part I: What Are Climate Researchers Saying About Western Water? A Guide for Non-Scientists

Part II: What Should Climate Researchers Know About the Realm of Western Water Law, Policy and Management?

Part III: Where to Find Additional Information


Stormwater Pollution Prevention Bmp Workshop, Demonstration, And Evaluation, Findlay G. Edwards Jun 2003

Stormwater Pollution Prevention Bmp Workshop, Demonstration, And Evaluation, Findlay G. Edwards

Arkansas Water Resources Center Technical Reports

With the recent promulgation of Phase II of the National Pollution Discharge Elimination System (NPDES) Stormwater Pollution Control regulations, many construction companies, consulting engineers, architects, and regulating agency personnel are unaware of the new stormwater pollution reduction requirements. In addition, they are typically unaware of Best Management Practices (BMPs) that are available to mitigate stormwater discharge pollution and the proper methods of installing and maintaining BMPs. The Water Quality Goals and Objectives were to train engineers, contractors, architects, and governmental officials on the new Phase II Storm Water NPDES regulations and Best Management Practices available for construction projects. The Original …


Hyperspectral Remote Sensing Protocol Development For Submerged Aquatic Vegetation In Shallow Waters, Charles R. Bostater Jr., T. Ghir, L. Bassetti, Carlton Hall, E. Reyier, R. Lowers, K. Holloway-Adkins, Robert Virnstein Feb 2003

Hyperspectral Remote Sensing Protocol Development For Submerged Aquatic Vegetation In Shallow Waters, Charles R. Bostater Jr., T. Ghir, L. Bassetti, Carlton Hall, E. Reyier, R. Lowers, K. Holloway-Adkins, Robert Virnstein

Ocean Engineering and Marine Sciences Faculty Publications

Submerged aquatic vegetation (SAV) is an important indicator of freshwater and marine water quality in almost all shallow water aquatic environments. Throughout the world the diversity of submerged aquatic vegetation appears to be in decline, although sufficient historical data, of sufficient quantitative quality is lacking. Hyperspectral remote sensing technology, available from low altitude aircraft sensors, may provide a basis to improve upon existing photographic regional assessments and monitoring concerned with the aerial extent and coverage of SAV. In addition, modern low altitude remote sensing may also help in the development of environmental satellite requirements for future satellite payloads. This paper …


The Effect On Water Quality Of Riverine Input Into Coastal Wetlands, Robert Raymond Lane Jan 2003

The Effect On Water Quality Of Riverine Input Into Coastal Wetlands, Robert Raymond Lane

LSU Doctoral Dissertations

This dissertation focuses on impact on water quality of two freshwater diversions, the Bonnet Carre Spillway and the Caernarvon freshwater diversion, as well as the Atchafalaya River Estuarine Complex. As water passed through the Bonnet Carre Spillway, there were reductions in total suspended sediment concentrations of 82-83%, in nitrite+nitrate of 28-42%, in total nitrogen (TN) of 26-30%, and in total phosphorus (TP) of 50-59%. The Si:N ratio generally increased and the N:P ratio decreased from the river to the plume edge in Lake Pontchartrain. At the Caernarvon diversion, there were reductions in concentrations of dissolved inorganic Si, N, and P …


Watershed-Scale Agricultural Land-Use Impact On Instream Physicochemical Parameters, William Dillahunty, Indrajeet Chaubey, Marty Matlock Jan 2003

Watershed-Scale Agricultural Land-Use Impact On Instream Physicochemical Parameters, William Dillahunty, Indrajeet Chaubey, Marty Matlock

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Nonpoint source (NPS) pollution is often the result of runoff losses from agricultural or urban areas. Even though the watershed approach to controlling NPS pollution is identified as the most efficient approach, data linking watershed scale land use and specific water quality implications are very limited. The objective of this study was to quantify the impact of agricultural land use on stream physico-chemical properties. The upper reach of Flint Creek was monitored at two sampling points draining an agricultural land. At each of these points, continuous measurement of stream characteristics such as temperature, dissolved oxygen (DO) concentration, depth, pH, and …


Illinois River 2001 Pollutant Loads At Arkansas Highway 59 Bridge, Marc A. Nelson, Thomas S. Soerens Sep 2002

Illinois River 2001 Pollutant Loads At Arkansas Highway 59 Bridge, Marc A. Nelson, Thomas S. Soerens

Arkansas Water Resources Center Technical Reports

Automatic water samplers and a U. S. Geological Survey gauging station were established in 1995 on the main stem of the Illinois River at the Arkansas Highway 59 Bridge. Since that time, continuous stage and discharge measurements and water quality sampling have been used to determine pollutant concentrations and loads in the Arkansas portion of the Illinois River. This report represents the results from the measurement and sampling for January 1, 2001 to December 31, 2001.


Quantification Of Land-Use Impact On Stream Water Quality, Scott Dennis, Indrajeet Chaubey, Brian Haggard Jan 2002

Quantification Of Land-Use Impact On Stream Water Quality, Scott Dennis, Indrajeet Chaubey, Brian Haggard

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Accelerated eutrophication of Beaver Lake in northwest Arkansas is a major environmental concern. When developing watershed-management plans to protect lake water quality, it is important that linkages among land-use activities and water quality of tributary streams be quantified. This study assessed longitudinal base-flow and storm-flow water quality at War Eagle Creek and quantified linkages between stream water quality and land-use conditions within the War Eagle Creek sub-watershed of the Beaver Lake watershed. We collected six water samples: three from base-flow conditions and three from storm-flow conditions during Spring 2002. In general, concentrations of nitrate nitrogen (NO3-N), total N (TN), total …


Illinois River 2000 Pollutant Loads At Arkansas 59 Bridge, Marc A. Nelson, Thomas S. Soerens Oct 2001

Illinois River 2000 Pollutant Loads At Arkansas 59 Bridge, Marc A. Nelson, Thomas S. Soerens

Arkansas Water Resources Center Technical Reports

Automatic water samplers and a U. S. Geological Survey gauging station were established in 1995 on the main stem of the Illinois River at the Arkansas Highway 59 Bridge. Since that time, continuous stage and discharge measurements and water quality sampling have been used to determine pollutant concentrations and loads in the Arkansas portion of the Illinois River. This report represents the results from the measurement and sampling for January 1, 2000 to December 31, 2000


A Comparison Of Phytoplankton Communities In Lake Prince And The Western Branch Reservoir, Suffolk, Virginia, Cara Marie Muscio Apr 2001

A Comparison Of Phytoplankton Communities In Lake Prince And The Western Branch Reservoir, Suffolk, Virginia, Cara Marie Muscio

Biological Sciences Theses & Dissertations

Lake Prince and the Western Branch Reservoir are two eutrophic bodies of water located in Suffolk, Virginia. Lake Prince and its two small tributaries join the Western branch via a constructed spillway. This lake system is a source of water for the surrounding municipalities, and a recreational area for community citizens. In the past, these bodies of water had repeated incidents of low oxygen and nuisance algal blooms, particularly cyanobacteria species. As a result aerators have been installed in the main body of both Lake Prince and the Western Branch Reservoir. In addition, a pipeline has been installed from North …


Extended Water Quality Monitoring Of The Lincoln Lake Watershed, Paul F. Vendrell, K. F. Steele, M. A. Nelson, L. W. Cash, R. W. Ncnew Dec 2000

Extended Water Quality Monitoring Of The Lincoln Lake Watershed, Paul F. Vendrell, K. F. Steele, M. A. Nelson, L. W. Cash, R. W. Ncnew

Arkansas Water Resources Center Technical Reports

For seven years, the Lincoln Lake (Moores Creek and Beatty Branch) watershed was monitored for improvements in water quality resulting from agricultural best management practices (BMP) implemented to reduce nutrient transport. During the first three years of monitoring (1991 to 1994), nitrogen transport declined significantly (Edwards et al., 1994, 1996, and 1997) under both base and storm flow conditions. This decline in nitrogen transport was again observed in the three-year period following 1994 (Vendrell et al. 1998). This monitoring effort has demonstrated that water quality bas improved in the Lincoln Lake watershed. However, since the nitrogen transport continued to decline …


Spatial And Temporal Changes In Land Use And Land Cover From 1988 To 1992 In The Upper White River Watershed, H. D. Scott, J. M. Mckimmey Sep 2000

Spatial And Temporal Changes In Land Use And Land Cover From 1988 To 1992 In The Upper White River Watershed, H. D. Scott, J. M. Mckimmey

Arkansas Water Resources Center Technical Reports

Changes in Land Use and Land Cover (LULC) in the upper White River Watershed from 1988 to 1992 were analyzed and plotted using the geographic information system known as Geographic Resources Analyses Support System (GRASS). This portion of the White River Watershed includes two sub-basins the East Fork and the Middle Fork. In addition, LULC changes were determined for two smaller sub-basins, Shumate Creek and Cannon Creek, located in the East Fork of the White River. The sources and methods of interpretation of the 1988 and 1992 of data were different. Thus, there were variations in how certain portions of …


Illinois River 1999 Pollutant Loads At Arkansas Higway 59 Bridge, Marc A. Nelson, Thomas S. Soerens Sep 2000

Illinois River 1999 Pollutant Loads At Arkansas Higway 59 Bridge, Marc A. Nelson, Thomas S. Soerens

Arkansas Water Resources Center Technical Reports

Automatic water samplers and aU. S. Geological Survey gauging station were established in 1995 on the main stem of the Illinois River at the Arkansas Highway 59 Bridge. Since that time, continuous stage and discharge measurements and water quality sampling have been used to determine pollutant concentrations and loads in the Arkansas portion of the Illinois River. This report represents the results from the measurement and sampling for January 1, 1999 to December 31, 1999.


An Examination Of Gasoline Pollutants From Two-Cycle Marine Engines Within Lake Mead National Recreation Area, Brian Carter May 2000

An Examination Of Gasoline Pollutants From Two-Cycle Marine Engines Within Lake Mead National Recreation Area, Brian Carter

UNLV Theses, Dissertations, Professional Papers, and Capstones

Jet skis are a very popular "toy" to have in the United States. They account for almost a third of all boat sales, and their numbers are growing rapidly. Unfortunately jet skis use two-cycle engines that pollute at unacceptable levels. Jet ski motors can emit up to 25% of its fuel right back into the water. This alarmed me and I wanted to take a deeper look into how bad jet skis pollute Las Vegas' primary water source. Lake Mead. I looked into how a two-cycle engine differs from a regular engine and I looked at the actual pollutants a …


High-Order Derivative Spectroscopy For Selecting Spectral Regions And Channels For Remote Sensing Algorithm Development, Charles R. Bostater Dec 1999

High-Order Derivative Spectroscopy For Selecting Spectral Regions And Channels For Remote Sensing Algorithm Development, Charles R. Bostater

Ocean Engineering and Marine Sciences Faculty Publications

A remote sensing reflectance model, which describes the transfer of irradiant light within a plant canopy or water column has previously been used to simulate the nadir viewing reflectance of vegetation canopies and leaves under solar induced or an artificial light ur'2 and the water surface reflectance3' Wavelength dependent features such as canopy reflectance leafabsorption and canopy bottom reflectance as well as water absorption and water bottom reflectance have been used to simulate or generate synthetic canopy and water surface reflectance signatures3' ' This paper describes how derivative spectroscopy can be utilized to invert the synthetic or modeled as well …


Wavelength-Specific Fluorescence Coefficients For Simulating Hyperspectral Reflectance Signatures Of Water, Charles R. Bostater, Jan Rebman Dec 1999

Wavelength-Specific Fluorescence Coefficients For Simulating Hyperspectral Reflectance Signatures Of Water, Charles R. Bostater, Jan Rebman

Ocean Engineering and Marine Sciences Faculty Publications

A model1'2 which describes the transfer of irradiant light in water is used to predict the fluorescence response ofthe water surface reflectance under solar induced or an artificial light source such as a laser. Formulations for the estimation of wavelength dependent fluorescent coefficients. The techniques allows the description ofa fluorescence reflectance response in deep and shallow waters with various bottom reflectance signatures such as submerged vegetation, corals and sand. Recent advances in the model are presented for obtaining wavelength dependent fluorescence spectrum responses from the solutions of the two flow equations following the procedures developed by Bostater1'2'3. Synthetic or modeled …


Storm And Base Flow Water Quality For Bear, Calf, And Tomahawk Creeks, Kenneth F. Steele, David N. Mott Oct 1998

Storm And Base Flow Water Quality For Bear, Calf, And Tomahawk Creeks, Kenneth F. Steele, David N. Mott

Arkansas Water Resources Center Technical Reports

Because of the conversion of 92,780 acres of forest to pasture land in the Buffalo River watershed over a 27 year period, there is concern about the affect of agricultural activities on the water quality of the river. Three tributaries (Bear, Calf and Tomahawk creeks) located about mid-length of the Buffalo River were chosen to investigate the affect of agricultural activity on water quality because these streams provide the greatest amounts of fecal bacteria, nitrate+nitrite and phosphorus to the river, despite comprising only 13% of the watershed.


Interagency Lake Mead And Las Vegas Wash Monitoring Program: Standard Operating Procedures Manual, Bureau Of Reclamation, City Of Henderson Water Reclamation Facility, City Of Las Vegas Water Pollution Control Facility, Clark County Sanitation District, Nevada, Southern Nevada Water Authority Oct 1998

Interagency Lake Mead And Las Vegas Wash Monitoring Program: Standard Operating Procedures Manual, Bureau Of Reclamation, City Of Henderson Water Reclamation Facility, City Of Las Vegas Water Pollution Control Facility, Clark County Sanitation District, Nevada, Southern Nevada Water Authority

Publications (WR)

A number of agencies sample Lake Mead and the Las Vegas Wash on a routine basis at several locations. In order to share and properly interpret the data, the Bureau of Reclamation, Southern Nevada Water Authority and the three Wastewater Treatment Facilities (City of Las Vegas, Clark County Sanitation District and City of Henderson) formed a committee to examine sampling and analytical protocols and to share information with the goal of maximizing the data quality. The group first met in April 1997. It was agreed that an effort should be made to discuss and compare specific sampling and analytical techniques …


Llinois River 1997 Pollutant Loads At Arkansas Highway 59 Bridge, Marc A. Nelson, Thomas S. Soerens Sep 1998

Llinois River 1997 Pollutant Loads At Arkansas Highway 59 Bridge, Marc A. Nelson, Thomas S. Soerens

Arkansas Water Resources Center Technical Reports

Automatic water samplers and a USGS gauging station were established in 1995 on the main stem of the Illinois River at the Arkansas Highway 59 Bridge. Since that time, continuous stage and discharge measurements and water quality sampling have been used to determine pollutant concentrations and loads in the Arkansas portion of the Illinois River. This report represents the results from the measurement and sampling for January 1, 1997 to December 31, 1997.


Specific Absorption And Backscatter Coefficient Signatures In Southeastern Atlantic Coastal Waters, Charles R. Bostater Sep 1998

Specific Absorption And Backscatter Coefficient Signatures In Southeastern Atlantic Coastal Waters, Charles R. Bostater

Ocean Engineering and Marine Sciences Faculty Publications

Measurements of natural water samples in the field and laboratory of hyperspectral signatures of total absorption and reflectance were obtained using long pathlength absorption systems (50 cm pathlength). Water was sampled in Indian River Lagoon, Banana River and Port Canaveral, Fl. Stations were also occupied in near coastal waters out to the edge ofthe Gulf Stream in the vicinity of Kennedy Space Center, Fl. and estuarine waters along Port Royal Sound and along the Beaufort River tidal area in South Carolina. The measurements were utilized to calculate natural water specific absorption, total backscatter and specific backscatter optical signatures. The resulting …


Las Vegas Wash Water Quality Monitoring Program: 1996 Report Of Findings, Richard A. Roline, James J. Sartoris, U.S. Bureau Of Reclamation, U.S. Geological Survey Apr 1997

Las Vegas Wash Water Quality Monitoring Program: 1996 Report Of Findings, Richard A. Roline, James J. Sartoris, U.S. Bureau Of Reclamation, U.S. Geological Survey

Publications (WR)

Las Vegas Wash, a natural wash east of the city of Las Vegas, Nevada, carries stormwater, groundwater drainage, and sewage effluent from three sewage treatment plants to Lake Mead. The Wash provides nearly the only surface water outlet for the entire 2,193 mi2 of Las Vegas Valley. A drainage area of 1,586 mi2 contributes directly to the Wash through surface flow which is channeled to Las Vegas Bay of Lake Mead, while drainage of the remaining 607 mi2 is presumably subsurface and may drain toward Las Vegas Wash.

In the 1930's and 1940's, sewage treatment plants were …


Application Of A Flow-Through Absorption Tube For Remotely Estimating Water-Quality Parameters, Charles Bostater, Melissa Keller, Manuel Gimond Jan 1997

Application Of A Flow-Through Absorption Tube For Remotely Estimating Water-Quality Parameters, Charles Bostater, Melissa Keller, Manuel Gimond

Ocean Engineering and Marine Sciences Faculty Publications

A flow through absorption tube is described and applied. The tube is similar in concept to a 50 cm pathlength cylindrical cuvette described previously by Bostater and Gimond.' The new absorption tube allows for continuous, underway measurements of water absorption signatures. Water is allowed to flow through the tube, and in this way the spectral change or track ofabsorption can be measured as a function oftime or space when operated from a stationary or moving platform. Data gathered from various environments ranging from very turbid to clear water is analyzed and described. Concentrations of chlorophyll-a, suspended matter, and dissolved organic …


Investigation Of The Statistical And Spatial Distributions Of Mercury Contaminated Fish, Surface Waters And Soils In Arkansas, H. D. Scott, J. M. Mckimmey Jan 1997

Investigation Of The Statistical And Spatial Distributions Of Mercury Contaminated Fish, Surface Waters And Soils In Arkansas, H. D. Scott, J. M. Mckimmey

Arkansas Water Resources Center Technical Reports

Mercury (Hg) contamination of fish is a widespread problem throughout much of the United States and the world (Louisiana WWW page, 1997). Levels ofHg in fish suffic1ent to exceed the FDA action level of 1 mg kg-1 have been found in many water bodies, including some in Arkansas and Louisiana. As a result of the serious public health ramifications for developing fetuses and for people that subsist on native fish, fish consumption advisories due to Hg contamination have been issued in 29 states. Contamination of surface water bodies by Hg results from deforestation, forest fires, fossil fuels, mining, natural emissions …


Effects Of Zebra, Mussel, Dreissena Polymorpha Infestation On Lake Dardanelle Water Quality, Charles J. Gagen, Joseph N. Stoeckel Jun 1996

Effects Of Zebra, Mussel, Dreissena Polymorpha Infestation On Lake Dardanelle Water Quality, Charles J. Gagen, Joseph N. Stoeckel

Arkansas Water Resources Center Technical Reports

Zebra mussels recently invaded southern waterways including the Arkansas River. Large-scale filtration of suspended particulate matter by dense populations could alter reservoir ecosystem function. Furthermore, they attach to hard surfaces, thereby threatening normal operations of artificial structures. We designed this study to provide baseline data prior to establishment of high population levels of zebra mussels in Lake Dardanelle. The characterization of spatial and temporal variability in water quality, zooplankton, phytoplankton, and macrophytes will allow testing of several hypotheses. We sampled zebra mussel veliger and settling juvenile densities and zooplankton densities at four fixed sites and the key water quality variables …


Identification Of Optimal Locations For Sampling Ground Water For Pesticides In The Mississippi Delta Region Of Eastern Arkansas, H. S. Lin, H. D. Scott, J. M. Mckimmey May 1996

Identification Of Optimal Locations For Sampling Ground Water For Pesticides In The Mississippi Delta Region Of Eastern Arkansas, H. S. Lin, H. D. Scott, J. M. Mckimmey

Arkansas Water Resources Center Technical Reports

Concerns about the presence of pesticides in the Mississippi River Valley alluvial aquifer in the Arkansas Delta have generated the need to develop a map of ground water vulnerability for this region comprised of approximately 10 million acres. Based on the availability of digital data and the scale of this study. we used a modified Pesticide DRASTIC model in a GRASS GIS environment to identify areas that were physically more sensitive to pesticide contamination than other areas within the Delta. Spatial distribution of pesticide loading was estimated from pesticide application rates in different crops and crop distribution map interpreted from …


An Introduction To Lake And Reservoir Water Quality Modeling, Kenneth H. Reckhow Mar 1996

An Introduction To Lake And Reservoir Water Quality Modeling, Kenneth H. Reckhow

Arkansas Water Resources Center Technical Reports

No abstract provided.


Nutrient Limitation In A Southwestern Desert Reservoir: Eutrophication Of Las Vegas Bay, Lake Mead, Nevada, Davine M. Lieberman Sep 1995

Nutrient Limitation In A Southwestern Desert Reservoir: Eutrophication Of Las Vegas Bay, Lake Mead, Nevada, Davine M. Lieberman

Publications (WR)

Algal bioassay tests were conducted with Selenastrum capricornutum and natural algae on inner Las Vegas Bay, Lake Mead, Nevada, from December 1992 through September 1993, to identify any nutrient limitation in an area of the reservoir that has experienced problems associated with severe nutrient enrichment. Three areas were sampled based on a gradient of water quality conditions that existed in Las Vegas Bay (LVB). Disodium ethylenedinitrilotetraacetate (EDTA) significantly stimulated algal growth compared to non-EDTA treatment. Algal bioassays indicated that phosphorus (P) was the primary limiting nutrient at all stations for most of the test dates. Chl a response with EDTA …