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University of Arkansas, Fayetteville

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Articles 151 - 180 of 258

Full-Text Articles in Soil Science

Characterizing Bean Pod Rot In Arkansas And Missouri, Jeremy H. Taylor, Craig S. Rothrock Jan 2004

Characterizing Bean Pod Rot In Arkansas And Missouri, Jeremy H. Taylor, Craig S. Rothrock

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

Green beans are an important crop grown for processing in both Arkansas and Missouri. Green beans are harvested mechanically using non-selective picking fingers. Harvested beans are then transported in bulk to processing plants that are located at various locations throughout the mid-South. Thus, the crop is managed for high quality, avoiding pod blemishes caused by insects and diseases. One of the consistent quality problems that affect Arkansas and Missouri green bean crops is pod rot. Two of the causal agents of pod rot that have been reported by researchers and vegetable companies alike are Pythium aphanidermatum and an unidentified Phytophthora …

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Assessment And Restoration Of A Neighborhood Wetland Invaded By Exotic Plant Species, Ryan Neal, Kimberly R. Payne, Lorena Moreno, Graham Duffy, Jonathan Peck, Mary C. Savin Jan 2004

Assessment And Restoration Of A Neighborhood Wetland Invaded By Exotic Plant Species, Ryan Neal, Kimberly R. Payne, Lorena Moreno, Graham Duffy, Jonathan Peck, Mary C. Savin

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

The University of Arkansas Crop, Soil, and Environmental Sciences (CSES) Club adopted a local wetland in the spring of 2002 through the Fayetteville Parks and Recreation Department. This project has allowed students to interact with local community and governmental organizations as well as other academic departments within the university. Students have gained valuable laboratory and field experience through characterizing hydric soils, identifying bird and plant species, and analyzing water quality, soil nutrients, and microbial biomass. Under the main goal of restoring the wetland, the club has outlined both short and long-term objectives including soil and water assessments; removal of two …

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Effects Of Vegetation Removal On Native Soil Quality In Eastern Arkansas, Lorena Moreno, Kristofor R. Brye Jan 2004

Effects Of Vegetation Removal On Native Soil Quality In Eastern Arkansas, Lorena Moreno, Kristofor R. Brye

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

Aboveground vegetation removal practices, such as cutting and baling and burning, can both positively and negatively affect a prairie ecosystem. Burning can stimulate growth and species diversity, but removing vegetation and the nutrients it contains without equal replenishment of those nutrients could cause a steady decline in available soil nutrients. The objective of this study was to evaluate the effects of vegetation removal techniques in a native tallgrass prairie in east-central Arkansas. Soil samples were collected from the top 10 cm in each soil mapping unit that existed in each of three prairie areas that differed by the amount of …

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Wayne E. Sabbe Arkansas Soil Fertility Studies 2002, Nathan A. Slaton Mar 2003

Wayne E. Sabbe Arkansas Soil Fertility Studies 2002, Nathan A. Slaton

Arkansas Agricultural Experiment Station Research Series

Rapid technological changes in crop management and production require that the research efforts also be presented in an expeditious manner. The contributions of soil fertility and fertilizers are major production factors in all Arkansas crops. The studies contained within will allow producers to compare their practices with the university’s research efforts. Additionally, soil test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.

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Soil Particle-Size Analysis: A Comparison Of Two Methods, Lauren Williams-Caudle, Kristofor Brye, E. Moye Rutledge Jan 2003

Soil Particle-Size Analysis: A Comparison Of Two Methods, Lauren Williams-Caudle, Kristofor Brye, E. Moye Rutledge

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

Knowing the proportion of particle sizes in soil is important to soil scientists and agronomists. The mixture of sand, silt, and clay influences water movement, solute transport, nutrient retention, and many other properties and processes in soil. The standard method for particle size determination is a somewhat time-consuming process. An equally accurate but shorter method would be appealing for many reasons. The objective of this study was to compare a standard method of particle-size analysis using a hydrometer to an abbreviated hydrometer method, which, instead of 12 h for the standard method, requires about 3 h to complete. Twenty-four soil …

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Soils Of Mississippi County, Arkansas, J. M. Mckimmey, B. Dixon, H. D. Scott, C. M. Scarlat Nov 2002

Soils Of Mississippi County, Arkansas, J. M. Mckimmey, B. Dixon, H. D. Scott, C. M. Scarlat

AAES Research Reports and Research Bulletins

Along with air and water, soil contributes essential processes to the natural order of global cycles. With the exception of edibles from the sea, virtually everything we, and most other land-based animals, eat is derived from soil. Soil is a storage medium of essential minerals and nutrients for fulfilling our agricultural and nutritional needs. Humans work the soil to provide the basics of food, clothing, and shelter. We also use the soil as a medium to store and discard our waste. Virtually everything we do is in some way connected to soil

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Land-Use Effects On Soil-Water Retention Characteristic, Naomi Colton, Kristofor Brye Jan 2002

Land-Use Effects On Soil-Water Retention Characteristic, Naomi Colton, Kristofor Brye

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

Tillage can negatively affect soil physical properties such as bulk density, organic matter content, and soil hydraulic properties, which in turn affect how plants grow. The objective of this study was to evaluate water retention characteristics of a Jay silt loam soil under cultivated agriculture and native tallgrass prairie in northwest Arkansas. Air-dry soil samples collected from 0-10 cm depth were re-wet with varying amounts of distilled water to create a range of water contents. After overnight equilibration, the water potential was measured on the re-wet soil samples using a dewpoint potentiameter. The relationship between water potential (Ψ) and water …

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

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

Arkansas Water Resources Center Technical Reports

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

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

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

Arkansas Water Resources Center Technical Reports

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

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Determination Of The Pollutant Loads In The Kings River Near Berryville, Thomas S. Soerens, Marc A. Nelson Mar 2001

Determination Of The Pollutant Loads In The Kings River Near Berryville, Thomas S. Soerens, Marc A. Nelson

Arkansas Water Resources Center Technical Reports

An automatic sampler and a U.S. Geological Swvey (USGS) gauging station were established in 1998 and water quality sampling was begun in 1999 on the Kings River near Benyville, Arkansas. Continuous stage and discharge measurements and frequent water quality sampling have been used to determine pollutant concentrations and loads in t11e river. In addition, ten samples were taken by Arkansas Water Resources Center (A WRC) concurrently with USGS samples in order to assess whether A WRC and USGS samples can be compared. This report presents the results from the sampling and analysis for January 1, I999 to December 31, 1999. …

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Demonstration Of Best Management Practices For The Protection And Improvement Of The Soil And Water Resources In The Arkansas Delta, M. A. Henslee, W. H. Baker, S. D. Carroll, J. L. Farris, S. D. Davis, C. D. Milam, J. L. Pierce Feb 2001

Demonstration Of Best Management Practices For The Protection And Improvement Of The Soil And Water Resources In The Arkansas Delta, M. A. Henslee, W. H. Baker, S. D. Carroll, J. L. Farris, S. D. Davis, C. D. Milam, J. L. Pierce

Arkansas Water Resources Center Technical Reports

This report is the compilation of a multi~year project that was directed at identifying the impact and possible mitigation solutions of non-point pollution from row crop agriculture in a watershed in the Arkansas Delta. The first part of the project involved an inventory of the condition of the major streams that make up the study watershed. The remainder of the project was focused at demonstrating and reporting best management nutrient and sediment runoff control practices (BMP) that could be implemented. The final assessment of the demonstration work is a GIS analysis that provides an overview of the effectiveness of these …

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Improvements In Turfgrass Color And Density Resulting From Comprehensive Soil Diagnostics, Matt Cordell, Jonathan Davis, David E. Longer Jan 2001

Improvements In Turfgrass Color And Density Resulting From Comprehensive Soil Diagnostics, Matt Cordell, Jonathan Davis, David E. Longer

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

There are roughly 220 golf courses in Arkansas, and as many as 50% of these courses were constructed using common bermudagrass fairways. Although resilient, common bermudagrass loses density and quality over time. In this experiment physical and chemical properties of the soil were analyzed to determine the causes of decline in turf quality observed on several fairways of a local golf course. Once a particular fairway was selected for study and preliminary soil sampling conducted, GS+, a geostatistical computer program, was used to map the location of certain chemical deficiencies. A moderate to severe Mg deficiency was detected throughout the …

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Improving Water Quality Through Bmps For Crop Production Systems Whole Farm Soil And Water Management, J. T. Gilmour, L. R. Frye, N. A. Slaton Dec 2000

Improving Water Quality Through Bmps For Crop Production Systems Whole Farm Soil And Water Management, J. T. Gilmour, L. R. Frye, N. A. Slaton

Arkansas Water Resources Center Technical Reports

The major objective of this demonstration project was to assess the usefulness of Global Positioning Systems/Geographic Information Systems (GPS/GIS), water testing, soil testing and yield monitoring in a whole farm water and soil management plan. An important part of this objective was to make recommendations to increase crop productivity and decrease the potential for surface water degradation through erosion and runoff at the farm. The farm was located on 2400 acres in the Bayou de View watershed in Monroe County, Arkansas. The farm lies approximately five miles southwest of the town of Brinkley straddling Highway 17 just south of its …

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Proceedings Of The Arkansas Water Resources Center Annual Conference: Environmental Hydrology, Kenneth F. Steele Nov 2000

Proceedings Of The Arkansas Water Resources Center Annual Conference: Environmental Hydrology, Kenneth F. Steele

Arkansas Water Resources Center Technical Reports

The papers and abstracts in these proceedings are the result of a joint conference of the Arkansas Water Resources Center (A WRC) with the SouthCentral Section of the Geological Society of America. The joint conference was a success with about 250 participants. A WRC sponsored two sessions on Environmental Hydrology and a short course titled "Hydrogeology and Geochemistry of Salt Water Contamination." The Environmental Hydrology presentations covered wide-ranging topics that reflect the diversity of the environmental settings across Arkansas. Topics ranged from salt water and critical ground water issues in the Delta to endangered species and interbasin ground-water recharge in …

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Investigation Of Optimum Sample Number And Timing For Determining Pollution Loads, T. S. Soerens, Marc A. Nelson Oct 2000

Investigation Of Optimum Sample Number And Timing For Determining Pollution Loads, T. S. Soerens, Marc A. Nelson

Arkansas Water Resources Center Technical Reports

In order to determine the impacts of non point source (NPS) pollution and to develop Total Maximum Daily Loads (Tr\tfDLs), accurate measurements of pollution loads in streams are critical. The objectives of this study were to accurately detemline pollutant loads at two sites by intensive storm sampling, to develop sub-sampling and other data analysis techniques, to detemline the effect of sample interval on load calculation accuracy, and to find the minimum sample interval required to determine storm loads at a required accuracy. The two stream sites used were a 1st order and a 3rd order stream in the Illinois River …

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Ground Water In Northwest Arkansas: Minimizing Nutrient Contamination From Non-Point Sources In Karst Terrane, R. K. Davis, J. V. Brahana, J. S. Johnston Sep 2000

Ground Water In Northwest Arkansas: Minimizing Nutrient Contamination From Non-Point Sources In Karst Terrane, R. K. Davis, J. V. Brahana, J. S. Johnston

Arkansas Water Resources Center Technical Reports

The purpose of the project is to evaluate the effectiveness of Best Management Practices (BPMs) in preventing non-point source contamination of the ground-water resources in the karst terrane of northwestern Arkansas. Limestone and dolomite aquifers in the region are highly vulnerable to contamination. Ground-water studies performed in the region during the last two decades indicate degradation of these carbonate aquifers by nutrients and bacteria. The expeditious growth of the poultry industry during this period, in combination with the inordinate population growth of the region constitute a threat to the ground-water resources from both point sources and non-point sources of contamination. …

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Economics Of Using On-Farm Reservoirs To Distribute Diverted Surface Water To Depleted Ground Water Areas Of The Southern Mississippi Valley Region, Eric J. Wailes, Kenneth B. Young, James Smartt, Gail L. Cramer Aug 2000

Economics Of Using On-Farm Reservoirs To Distribute Diverted Surface Water To Depleted Ground Water Areas Of The Southern Mississippi Valley Region, Eric J. Wailes, Kenneth B. Young, James Smartt, Gail L. Cramer

Arkansas Water Resources Center Technical Reports

Rapid ground water depletion has become a significant problem for parts of the Southern Mississippi River Valley. In 1997, the Arkansas Soil and Water Conservation Commission (ASWCC) declared six counties in the Grand Prairie of Arkansas critical ground water areas. A proposed solution to the ground water depletion problem in this region is to divert surplus flows from the White River by a canal system to the farmer stakeholders. To make the system work, on-farm reservoirs will be needed to store and manage the diverted surface water for crop irrigation use during the growing season.

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Influence Of Nitrogen Rate And Sampling Date On Soil Analysis Values Of Highbush Blueberries, John R. Clark, Ronald W. Mcnew, Richard C. Maples Jun 1999

Influence Of Nitrogen Rate And Sampling Date On Soil Analysis Values Of Highbush Blueberries, John R. Clark, Ronald W. Mcnew, Richard C. Maples

AAES Research Reports and Research Bulletins

Three studies were conducted on nitrogen (N) fertilization effects on soil of highbush blueberries in Arkansas. Objectives included: 1) determination of varying N rate effects on the standard soil analysis variables, 2) determination of date of soil sampling effects on soil analyses, 3) evaluation of the interactions of N rate and time of sampling, and 4) determination of changes in soil content over years. This research was done in two of the more important highbush blueberry production areas in Arkansas: the Arkansas River Valley where blueberries are grown on sandy loam soils, and northwest Arkansas where production is more common …

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Arkansas Soil Fertility Studies 1998, Wayne Sabbe Mar 1999

Arkansas Soil Fertility Studies 1998, Wayne Sabbe

Arkansas Agricultural Experiment Station Research Series

Rapid technological changes in crop management and production require that the research efforts also be presented in an expeditious manner. The contributions of soil fertility and fertilizers are major production factors in all Arkansas crops. The studies contained within will allow producers to compare their practices with the university’s research efforts. Additionally, soil test data and fertilizer sales are presented to allow comparisons among years, crops, and other areas within Arkansas.

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Changes In Soil Chemistry Beneath Exposed Poultry House Pads And Manure Storage Areas, Stanley L. Chapman, William R. Teague Jan 1999

Changes In Soil Chemistry Beneath Exposed Poultry House Pads And Manure Storage Areas, Stanley L. Chapman, William R. Teague

Journal of the Arkansas Academy of Science

Concerns about nitrates in private drinking water supplies in the older poultry growing areas of Arkansas prompted soil and water testing in the early 1990's. Exposed poultry house pads were recognized as a potential source of nitrates in the groundwater. Soils beneath nine different poultry house pads in five counties were sampled in 10-30 cm increments to bedrock or to a maximum sampling depth of 90 cm. The nine sites had been exposed to natural weathering conditions ranging from never to for more than 20 years. Routine soil tests were conducted by the University of Arkansas Soil Testing Lab at …

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Vulnerability And Use Of Ground And Surface Waters In The Southern Mississippi Valley Region, H. Don Scott Sep 1998

Vulnerability And Use Of Ground And Surface Waters In The Southern Mississippi Valley Region, H. Don Scott

Arkansas Water Resources Center Technical Reports

There is a concern in the Southern Mississippi River Valley of the United States over non-point source pollution of ground and surface waters resulting from activities associated with agricultural production. This agriculturally intensive region consists of two major land resource areas (MLRAs): Southern Mississippi Valley Silty Uplands (MLRA 134) and the Southern Mississippi Valley Alluvium (MLRA 131). Both MLRAs have level to undulating and rolling topography, relatively fertile soils and a climate particularly conducive for row crop production.

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Agricultural Water Management In The Missippi Delta Region Of Arkansas, H. Don Scott, James A. Ferguson, Linda Hanson, Todd Fugitt, Earl Smith Aug 1998

Agricultural Water Management In The Missippi Delta Region Of Arkansas, H. Don Scott, James A. Ferguson, Linda Hanson, Todd Fugitt, Earl Smith

AAES Research Reports and Research Bulletins

Agriculture is the largest use of soil and water resources in eastern Arkansas. This bulletin summarized the recent historical use of soil and water by agriculture and the impact of irrigation on yields of rice, soybeans and cotton. The experiments conducted in the field to quantitatively schedule irrigations of crops are summarized. The results show the close relationship between the irrigation of crops and the extraction of water from the Alluvial Aquifer. The implications of this relationaship for the future are discussed.

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Arkansas Soil Fertility Studies 1997, Wayne E. Sabbe Apr 1998

Arkansas Soil Fertility Studies 1997, Wayne E. Sabbe

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

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Description Of The Sections And Subsections Of The Interior Highlands Of Arkansas And Oklahoma, Thomas L. Foti, George A. Bukenhofer Jan 1998

Description Of The Sections And Subsections Of The Interior Highlands Of Arkansas And Oklahoma, Thomas L. Foti, George A. Bukenhofer

Journal of the Arkansas Academy of Science

Sections and subsections of the Interior Highlands of Arkansas and Oklahoma are redefined, mapped and briefly summarized. The map was produced to support the Ozark- Ouachita Highlands Assessment (OOHA), being conducted by the USDA Forest Service. It revises the USDA Forest Service map "Ecological units of the eastern United States, first approximation" by Keys et al. (1995) and the earlier maps of the natural divisions of Arkansas (Foti, 1974; Foti, 1976; Pell, 1983) to reflect new knowledge and to achieve consistency with units recognized in Missouri. Four sections (natural divisions) are defined as opposed to the three of the previous …

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Arkansas Soil Fertility Studies 1996, Wayne E. Sabbe Apr 1997

Arkansas Soil Fertility Studies 1996, Wayne E. Sabbe

Arkansas Agricultural Experiment Station Research Series

No abstract provided.

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Influence Of Rice Production On The Quality Of Water In Tailwater Collection Reservoirs, R. A. Dewell, T. L. Lavy Jun 1996

Influence Of Rice Production On The Quality Of Water In Tailwater Collection Reservoirs, R. A. Dewell, T. L. Lavy

Arkansas Water Resources Center Technical Reports

Since maintaining high water quality standards in the state remains a high priority, monitoring for pesticides in water sources must continue. Determining the type, concentration, and characteristics of any pesticides present in water supplies are essential to the overall assessment of water quality. Five independent locations, implementing contained water management systems and recyclable water, were monitored in 1995 and 1996. Irrigation, runoff, and pond water samples were collected every 10 to 14 days between permanent flood establishment and draining. Water samples were transported to the laboratory and extracted for 16 pesticides using solid phase extraction (SPE) techniques. Quantification and confirmation …

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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 …

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Bioaccumulation Of Methyl Mercury Through A Food Chain, J. T. Knight Jun 1996

Bioaccumulation Of Methyl Mercury Through A Food Chain, J. T. Knight

Arkansas Water Resources Center Technical Reports

The bioaccumulation of mercury through the food chain has received much attention in Arkansas during the last three years. The discovery of mercury contamination and subsequent fish consumption advisories in southwest Arkansas have increased public awareness of the potential for bioaccumulation of different toxic compounds. It is postulated that the mercury problem in Arkansas is a result of methylation and resulting bioaccumulation of mercury as methyl mercury. This study was designed to derive a Bioaccumulation Factor (BAF) for mercury in a simple food chain under controlled conditions. A BAF is calculated by dividing the concentration found in the organism by …

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Survival Of Fecal Contamination Indicator Organisms In Soil, K. A. Teague, D. C. Wolf, P. F. Vendrell Sep 1995

Survival Of Fecal Contamination Indicator Organisms In Soil, K. A. Teague, D. C. Wolf, P. F. Vendrell

Arkansas Water Resources Center Technical Reports

Soils amended with human or animal waste may result in pathogen contamination of ground and surface water. Because temperature has been shown to affect pathogen survival, two laboratory studies were conducted to evaluate the impact of extremes in temperature on bacterial and viral pathogen indicator die-off in soil. A Captina silt loam was amended with broiler litter (0.1 g/g dry soil), septic tank effluent, or Escherichia coli (ATCC 13706) culture (both at 0.04 and 0.1 mL/g dry soil in the two respective studies), incubated at 5 and 35°C, and analyzed over time to determine the number of fecal coliform, E. …

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Spatial Distribution Of The Surface Geology And 1992 Land Use Of The Buffalo River Watershed, Kimberly R. Hofer, H. Don Scott, James M. Mckimmey Jul 1995

Spatial Distribution Of The Surface Geology And 1992 Land Use Of The Buffalo River Watershed, Kimberly R. Hofer, H. Don Scott, James M. Mckimmey

Arkansas Water Resources Center Technical Reports

The Buffalo River was established by Congress in 1972 as the first National River in the United States and is one of the few remaining free-flowing streams in Arkansas . The Buffalo River flows through the three major physiographic provinces of northern Arkansas, originating in the higher elevations of the Boston Mountains, and flowing generally northeastward to cut through the Springfield and Salem Plateaus. It drops from approximately 2000 feet in the headwaters to around 500 feet above sea level at its confluence with the White River in Marion County. The Buffalo River is considered to be one of Arkansas' …

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