Open Access. Powered by Scholars. Published by Universities.®

Hydrology Commons™

Open Access. Powered by Scholars. Published by Universities.®

University of Arkansas, Fayetteville

Discipline
Keyword
Publication Year
Publication
Publication Type

Articles 91 - 120 of 183

Full-Text Articles in Hydrology

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.

Go to article

Morphometry And Limnology Of Ferguson Lake, Saline County, Arkansas, John D. Rickett, E. P. (Perk) Floyd Jan 1999

Morphometry And Limnology Of Ferguson Lake, Saline County, Arkansas, John D. Rickett, E. P. (Perk) Floyd

Journal of the Arkansas Academy of Science

To more fully understand Ferguson Lake as an ecosystem and eventually relate its water quality and production potential to fisheries management, several limnological variables were sampled monthly from April 1997 through March 1999. Vertical profiles of temperature and dissolved oxygen were recorded, and water samples from 0.5 m. depth were tested for turbidity, pH, total alkalinity, total hardness, ortho-phosphate, nitrate-nitrogen, sulfate, iron and specific conductance. Evaporation rate experiments, spillway discharge and rainfall records were used to estimate lake hydrology. Depth transects on the lake and USGS topographic maps were used to measure and calculate morphometric and watershed features. The lake …

Go to article

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.

Go to article

Hydrogeological And Hydrochemical Connection Between The Decatur City Spring And Crystal Lake, Benton County, Arkansas, Demetra O. Salisbury, Ralph K. Davis Jan 1997

Hydrogeological And Hydrochemical Connection Between The Decatur City Spring And Crystal Lake, Benton County, Arkansas, Demetra O. Salisbury, Ralph K. Davis

Journal of the Arkansas Academy of Science

Arkansas is ranked nationally in the production of broilers, laying hens, turkey, swine and beef cattle. These animals produce large volumes of waste, which are spread on pasture land as a method of disposal, as well as a source of fertilizer, resulting in nonpoint source contamination of surface water and ground water. One area of concern includes the Decatur City Spring, which provides municipal water for the city of Decatur. A total of eight sites in the surrounding area were monitored routinely for water quality parameters, including pH, specific conductance, and nitrate-nitrogen. Water temperature and spring and lake stage were …

Go to article

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 …

Go to article

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 …

Go to article

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 …

Go to article

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. …

Go to article

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' …

Go to article

Spatial And Temporal Analysis Of The Morphological And Land Use Characteristics Of The Buffalo River Watershed, H. Don Scott, Kimberly R. Hofer Jul 1995

Spatial And Temporal Analysis Of The Morphological And Land Use Characteristics Of The Buffalo River Watershed, H. Don Scott, Kimberly R. Hofer

Arkansas Water Resources Center Technical Reports

The Buffalo River was established by Congress iQ. 1972 as the first National River in the United States. The Buffalo River, which originates in the higher elevations of the Boston Mountains in Newton County, is one of the few remaining free-flowing streams in Arkansas. It is considered to be one of Arkansas' greatest natural treasures, and thus, there is strong interest in protecting it from anthropogenic influences. An initial characterization of the soil taxonomic units, watershed boundaries, topography and physiographic units in the Buffalo River Watershed was presented by Scott and Smith (1994). The spatial distribution of the geologic units …

Go to article

Effects Of Zebra Mussel, Dreissena Polymorpha, Infestation On Lake Dardanelle Water Quality, Charles J. Gagen, Joseph N. Stoeckel Jun 1995

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. Exponential population growth and high filtration capacity of dense populations could alter reservoir ecosystem function. Furthermore, they attach to hard surfaces; thus, threatening normal operations of many artificial structures. We designed this study to provide baseline data prior to 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 density and zooplankton at four fixed sites and the other key variables at three of these sites biweekly …

Go to article

Assessment Of Effectiveness Of Buffer Zones In Removing Impurities In Runoff From Areas Treated With Poultry Litter. Part Ii: Source Areas To Buffer Areas Ratio Effects, P. Srivastava, D. R. Edards, T. C. Daniel Jun 1995

Assessment Of Effectiveness Of Buffer Zones In Removing Impurities In Runoff From Areas Treated With Poultry Litter. Part Ii: Source Areas To Buffer Areas Ratio Effects, P. Srivastava, D. R. Edards, T. C. Daniel

Arkansas Water Resources Center Technical Reports

Vegetative filter strips (VFS) are known to reduce runoff losses of nutrients. solids. and other materials from land areas treated with fertilizers . Although VFS effectiveness is known to depend partially on the relative lengths of filter and pollutant source areas. there is little experimental evidence available to quantify this dependence. This is particularly the case when VFS are implemented down-slope of pasture areas treated with animal manures such as poultry litter. This study assessed the influences of pollutant source area (treated with poultry litter) and VFS lengths on VFS removal of total Kjeldahl nitrogen (TKN). ammonia nitrogen (NH3 -N …

Go to article

Phosphorus Immobilization In Poultry Litter And Litter-Amended Soils With Aluminum, Calcium And Iron Amendments, D. M. Miller, P. A. Moore Jr., T. C. Daniels Sep 1994

Phosphorus Immobilization In Poultry Litter And Litter-Amended Soils With Aluminum, Calcium And Iron Amendments, D. M. Miller, P. A. Moore Jr., T. C. Daniels

Arkansas Water Resources Center Technical Reports

Arkansas produces approximately one billion broilers each year. Phosphorous (P) runoff from fields receiving poultry litter is believed to be one of the primary factors affecting water quality in Northwest Arkansas. Poultry litter contains approximately 20 g P kg-1, of which about 2 g P kg-1 is water soluble. Soils that have received repeated heavy applications of litter may have water soluble P contents of as high as 10 mg P Kg-1 soil. The objective of this study was to determine if soluble P levels could be reduced in poultry litter and litter-amended soils with Al,Ca, and/or Fe amendments. Poultry …

Go to article

The Prediction Of Sediment And Nutrient Transport In The Buffalo River Watershed Using A Geographic Information System, H. D. Scott, P. A. Smith Jun 1994

The Prediction Of Sediment And Nutrient Transport In The Buffalo River Watershed Using A Geographic Information System, H. D. Scott, P. A. Smith

Arkansas Water Resources Center Technical Reports

The Buffalo River was established by Congress in 1972 as the first National River in the United States. It is one of the few remaining free-flowing streams in northern Arkansas. The river originates in the higher elevations of the Boston Mountains in Newton County, and generally flows northeastward, intersecting the Springfield and Salem Plateaus as it drops from approximately 2000 feet in the headwaters to around 500 feet at the confluence with the White River in Marion County. It is considered by many to be one of Arkansas' greatest natural treasures, and therefore , there is strong interest in protecting …

Go to article

Correlating Soil Test Phosphorus Losses In Runoff, D. H. Pote, T. C. Daniel, P. A. Moore Jr., D. J. Nichols, D. R. Edwards, A. N. Sharpley Jun 1994

Correlating Soil Test Phosphorus Losses In Runoff, D. H. Pote, T. C. Daniel, P. A. Moore Jr., D. J. Nichols, D. R. Edwards, A. N. Sharpley

Arkansas Water Resources Center Technical Reports

Phosphorus in agricultural runoff is often a major cause of accelerated eutrophication of lakes and streams. Previous research has indicated that the amount of dissolved P (DP) in runoff is directly related to P content of the surface soil. Decades of fertilizer application at rates exceeding those of crop uptake have elevated soil test P (STP) levels in areas of intensive crop and livestock production, making this the major source of DP loss in runoff. The objective of our experiment was to relate STP content of Captina silt loam to P concentration and loss in runoff, and determine which STP …

Go to article

Assessment Of Effectiveness Of Buffer Zones In Removing Impurites In Runoff From Areas Treated With Poultry Litter, I. Chaubey, D. R. Edwards, T. C. Daniels Jun 1994

Assessment Of Effectiveness Of Buffer Zones In Removing Impurites In Runoff From Areas Treated With Poultry Litter, I. Chaubey, D. R. Edwards, T. C. Daniels

Arkansas Water Resources Center Technical Reports

Land application of animal manures (e.g. poultry litter, poultry manure, and swine manure) to pasture and range can lead to runoff quality degradation during storms that occur soon after application. Vegetative filter strips (VFS) have been shown to reduce pollution in runoff from row-cropped areas but have not been extensively studied in pasture and range settings. This research involved characterizing performance of fescue VFS in improving quality of runoff from pasture land areas treated with poultry litter and swine manure. The VFS were found to be quite effective in reducing off-site transport of ammonia nitrogen (NH3-N), total Kjeldahl nitrogen (TKN), …

Go to article

Nutrient Content Of Runoff Water From Rice Fields, C. E. Wilson Jr., P. A. Moore Jr., R. J. Norman, B. R. Wells Jun 1993

Nutrient Content Of Runoff Water From Rice Fields, C. E. Wilson Jr., P. A. Moore Jr., R. J. Norman, B. R. Wells

Arkansas Water Resources Center Technical Reports

Current perception is that nutrient runoff from croplands is a significant contributor to poor water quality in some areas. While extensive research has been conducted to survey and ameliorate this problem for several upland crops, little work has been done to evaluate the problem with flooded rice (Oryza sativa, L.) soils. Since rice production utilizes a major portion of the total irrigation water usage for certain areas, it is important to understand the contribution of rice production to non-point source N and P in surface water. Several production fields were selected to evaluate the concentrations of nutrients in the floodwater …

Go to article

The Influence Of Reservoir Basin Morphometry On Phytoplankton Community Structure, Richard L. Meyer, G. Keith Trost Jun 1993

The Influence Of Reservoir Basin Morphometry On Phytoplankton Community Structure, Richard L. Meyer, G. Keith Trost

Arkansas Water Resources Center Technical Reports

The research protocol was designed to compare three reservoirs with similar physical environments but different morphometry. Three reservoirs on the western edge of the Ozark uplift were selected because of their similar substrate and climatic condition. The reservoirs primarily differed in morphometry. Two of the reservoirs were of identical size, Bob Kidd and Prairie Groves Lakes, but of different configuration, semicircular and linear, respectively. The bifurcated lake, Lincoln Lake, was of smaller size. Each lake is dimictic. Each of the lakes were nitrate-N limited while soluble reactive phosphorus-P is available and not restricting the growth of phytoplankton. Although the pattern …

Go to article

Prediction And Management Of Sediments Load And Phosporus In The Beaver Reservoir Watershed Using A Geographic Information System, J. M. Mckimmey, H. D. Scott Jun 1993

Prediction And Management Of Sediments Load And Phosporus In The Beaver Reservoir Watershed Using A Geographic Information System, J. M. Mckimmey, H. D. Scott

Arkansas Water Resources Center Technical Reports

A study was conducted to compile a GIS database for the Beaver Reservoir Watershed and then use the database to run the Universal Soil Loss Equation and the Phosphorus Index Model on the War Eagle Creek Watershed, a portion of the Beaver Reservoir Watershed database. Characterization of the spat i a 1 properties of the primary attributes compiled for the watershed were reported. In addition, water quality samples taken from War Eagle Creek were analyzed for relationships across the watershed. Erosion in the watershed was lower than expected with well vegetated and fertilized pastures contributing to the reduction of annual …

Go to article

Effect Of Drying On Cyromazine Loss From Surface-Applied Caged-Layer Manure, T. C. Daniel, D. H. Pote, D. R. Edwards Jun 1993

Effect Of Drying On Cyromazine Loss From Surface-Applied Caged-Layer Manure, T. C. Daniel, D. H. Pote, D. R. Edwards

Arkansas Water Resources Center Technical Reports

In Arkansas, much of the environmental concern related to water quality has focused on the high volume of poultry fecal waste spread on the surf ace of local pastures to fertilize forage grass. Cyromazine (N-cyclopropyl-1,3,5-triazine-2,4,6- triamine), a feed-through larvicide used to control house flies (Musca domestica), is often a component of caged-layer manure. Cyromazine is quite soluble and stable in water, and previous research has shown that it can be readily washed from pasture plots by intense rainfall. Therefore, a study was conducted to evaluate increased drying time as a best management practice technique for reducing cyromazine runoff losses from …

Go to article

Computer Simulation Model Calibration And Validation For Prediction Of Water Quality Impacts Of Poultry Waste Disposal, D. R. Edwards, T. C. Daniel Jun 1993

Computer Simulation Model Calibration And Validation For Prediction Of Water Quality Impacts Of Poultry Waste Disposal, D. R. Edwards, T. C. Daniel

Arkansas Water Resources Center Technical Reports

Runoff and water quality data collected from two pairs of grazed fields in northwestern Arkansas were analyzed to support efforts to model runoff quality from areas receiving poultry manure and other fertilizer sources. The monitoring period described in this report was September 1, 1991 to April 30, 1993. One of each pair of fields was fertilized with inorganic fertilizer, and the other received either poultry litter or manure. Losses of fertilizer constituents were quite low from an agronomic standpoint, ranging from approximately 2-11 kg N/ha/year and 0.5-4.1 kg P04-P/ha/year. Annual losses of fertilizer constituents were dominated by only a small …

Go to article

Arkansas Agricultural Chemical Ground-Water Management Plan, Gerald King, Darryl Little, Tim Jessup, Charles Armstrong Oct 1992

Arkansas Agricultural Chemical Ground-Water Management Plan, Gerald King, Darryl Little, Tim Jessup, Charles Armstrong

Arkansas Water Resources Center Technical Reports

The Arkansas Agricultural Chemical Ground-Water Management Plan (SMP) is based on the Draft State Pesticide Ground- Water Management Plan Guidance and The Pesticides and Ground-Water Protection Strategy prepared by the U.S. Environmental Protection Agency (EPA). The need for a plan to protect ground water from contamination by agricultural chemicals and agents arises from evidence nationwide that using these chemicals can, in some instances, lead to contamination. In February 1988, EPA proposed a strategy to regulate certain pesticides by prohibiting their use in areas vulnerable to leaching unless a state develops and implements an acceptable management plan. The advantage of a …

Go to article

Arkansas Agricultural Chemical Ground-Water Management Plan - Appendices, Gerald King, Darryl Little, Tim Jessup, Charles Armstrong Jul 1992

Arkansas Agricultural Chemical Ground-Water Management Plan - Appendices, Gerald King, Darryl Little, Tim Jessup, Charles Armstrong

Arkansas Water Resources Center Technical Reports

The Arkansas Agricultural Chemical Ground-Water Management Plan (SMP) is based on the Draft State Pesticide Ground- Water Management Plan Guidance and The Pesticides and Ground-Water Protection Strategy prepared by the U.S. Environmental Protection Agency (EPA). The need for a plan to protect ground water from contamination by agricultural chemicals and agents arises from evidence nationwide that using these chemicals can, in some instances, lead to contamination. In February 1988, EPA proposed a strategy to regulate certain pesticides by prohibiting their use in areas vulnerable to leaching unless a state develops and implements an acceptable management plan. The advantage of a …

Go to article

Gis Characterization Of Beaver Watershed, H. D. Scott, J. M. Mckimmey Jun 1992

Gis Characterization Of Beaver Watershed, H. D. Scott, J. M. Mckimmey

Arkansas Water Resources Center Technical Reports

Beaver Reservoir watershed is located in Northwest Arkansas including portions of Madison, Washington, Benton, Carroll, Franklin and Crawford counties. This watershed is important to the Northwest Arkansas region because it supplies most of the drinking water for the major towns and cities, and several rural water systems. The watershed consists of 308,971 ha with elevations ranging from approximately 341 m to 731 m above mean sea level. It includes the Springfield Plateau and the Boston Mountains provinces within the Ozark Plateau physiographic region. There are approximately 581 km of streams, 532 km of shore line, and 3712 km of roads …

Go to article

Evaluation Of The Water Quality Impacts Of Land Application Of Poultry Litter, T. C. Daniels, D. R. Edwards Jun 1992

Evaluation Of The Water Quality Impacts Of Land Application Of Poultry Litter, T. C. Daniels, D. R. Edwards

Arkansas Water Resources Center Technical Reports

Evaluating the effect of land application of animal waste on water quality is fraught with inherent variability due to differing infiltration rates, slope, rainfall intensity and etc . Simulated rainfall technology has been used in erosion research for decades. Generally, this technology is used on plots of sufficient size (25 x 5 m) to develop rill and interrill erosion. The object of this investigation was to adapt and modify existing rainfall simulation technology used in soil erosion research for use in evaluating water quality impacts of land application of animal waste, and to test, evaluate and demonstrate it's scientific validity. …

Go to article

Effect Of Land Application Of Poultry Waste On Pesticide Loss, T. C. Daniel, D. R. Edwards Jun 1992

Effect Of Land Application Of Poultry Waste On Pesticide Loss, T. C. Daniel, D. R. Edwards

Arkansas Water Resources Center Technical Reports

The poultry industry in Arkansas is a large, concentrated, growing industry that produces a high volume of fecal waste. Most of this waste is surface applied as pasture fertilizer. Pesticides are commonly used in the poultry industry for fly and litter beetle contro land are often a component of the surface-applied poultry waste. No information exists in the scientific literature regarding the transport of this pesticide component to nearby water supplies.Our research focused on cyromazine, a feed-through larvicide used to control flies in caged-layer hen houses. Tetrachlorvinphos and carbaryl are also used in poultry waste, but these pesticides have a …

Go to article

Determination Of Optimal Timing Of Poultry Waste Disposal By Meteorological, Hydrological, And Water Quality Modeling Techniques, D. R. Edwards, T. C. Daniel Jun 1991

Determination Of Optimal Timing Of Poultry Waste Disposal By Meteorological, Hydrological, And Water Quality Modeling Techniques, D. R. Edwards, T. C. Daniel

Arkansas Water Resources Center Technical Reports

Approximately one million Mg of broiler litter were generated in conjunction with Arkansas' 1989 broiler production. Common practices for disposal of the waste have the potential to damage the quality of downstream rivers and lakes. This possibility is enhanced due to the concentration of broiler production in areas of the state with shallow soils, steep slopes, and limited suitable disposal area. Since the risk of pollution is greatest immediately following disposal and increases with rainfall depth and intensity, adverse water quality impacts may be mitigated by timing the application to coincide with low probability of surface losses of the nutrients …

Go to article

The Aquatic Macroinvertebrates Of The White River National Wildlife Refuge, Steve W. Chordas Iii, George L. Harp Jun 1991

The Aquatic Macroinvertebrates Of The White River National Wildlife Refuge, Steve W. Chordas Iii, George L. Harp

Arkansas Water Resources Center Technical Reports

The primary purpose of this study was to survey the diversity of the aquatic macroinvertebrates of the White River National Wildlife Refuge (WRNWR). Determining relative abundance and distributional and seasonal patterns were secondary objectives. No comprehensive investigations of the WRNWR aquatic macroinvertebrates had been conducted previously, and it was hypothesized that this relatively undisturbed area may serve as a refugium. Further, this study provides base line data by which management programs can be composed. Thirty sampling stations were established within the WRNWR. Samples were collected from north to south at a basic rate of five stations per month. Revisit collections …

Go to article

Water Quality As Affected By Pesticides In Rice Production, W. G. Johnson, T. L. Lavy, J. D. Mattice, B. W. Skulman, R. E. Talbert, R. J. Smith Jun 1991

Water Quality As Affected By Pesticides In Rice Production, W. G. Johnson, T. L. Lavy, J. D. Mattice, B. W. Skulman, R. E. Talbert, R. J. Smith

Arkansas Water Resources Center Technical Reports

Studies were conducted to determine the environmental persistence of the rice pesticides triclopyr, 2,4-D, benomyl and quinclorac. Triclopyr half-lives ranged from <7 d to >100 d depending on depth within the soil profile and clay content. Triclopyr persistence increased as depth within the profile increased and clay content increased. The benomyl metabolite MBC was present at greater than 50% of the initial amount after 9 months in the field. In simulated carryover field studies quinclorac exhibited the greatest potential for injury to subsequent rotational crops. Cotton and soybean growth was reduced when planted at four weeks after quinclorac application. The adsorption of triclopyr …

Go to article

Determination Of The Abient Toxicity Of The Tailwater Of Nimrod Lake, John T. Knight Jun 1991

Determination Of The Abient Toxicity Of The Tailwater Of Nimrod Lake, John T. Knight

Arkansas Water Resources Center Technical Reports

The objective of this research was to determine if ambient toxicity exists in the receiving stream below a reservoir in which water from the hypolimnion is released. The Ceriodaphnia 7-day test was utilized to determine if toxicity existed. This test is routinely used in the monitoring of municipal and industrial effluent. It has also been utilized in determining if ambient toxicity exists within receiving streams. Nimrod Lake is a flood control impoundment on the Fourche LaFave River in west central Arkansas. The literature suggest that during stratification the hypolimnetic release contains high levels of iron, manganese, ammonia and sulfide during …

Go to article

First Prev Next Last