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R.H. Coupe

Publications and source records attributed to R.H. Coupe.

10 recordsLinked to original sources
USGS2007

Use of a watershed model to characterize the fate and transport of fluometuron, a soil-applied cotton herbicide, in surface water

The Soil and Water Assessment Tool (SWAT) was used to characterize the fate and transport of fluometuron (a herbicide used on cotton) in the Bogue Phalia Basin in northwestern Mississippi, USA. SWAT is a basin-scale watershed model, able to simulate hydrological, chemical, and sediment transport processes. After adjustments to a few parameters (specifically the SURLAG variable, the runoff curve number, Manning's N for overland flow, soil available water capacity, and the base-flow alpha factor) the SWAT model fit the observed streamflow well (the Coefficient of Efficiency and R2 were greater than 60). The results from comparing observed fluometuron concentrations with simulated concentrations were reasonable. The simulated concentrations (which were daily averages) followed the pattern of observed concentrations (instantaneous values) closely, but could be off in magnitude at times. Further calibration might have improved the fit, but given the uncertainties in the input data, it was not clear that any improvement would be due to a better understanding of the input variables. ?? 2007 Taylor & Francis.

International Journal of Environmental Analytical ↗
USGS2004

Water-soluble pesticides in finished water of community water supplies

To evaluate the effect of the treatment process on pesticide concentration, source water and finished (treated) water samples were collected from 12 community water systems (CWSs) and analyzed for water-soluble pesticides. The pesticides most frequently detected in the source water were the triazine herbicides (atrazine, cyanazine, prometon, and simazine) and the chloroacetanilide herbicides (acetochlor, alachlor, and metolachlor). Atrazine, metolachlor, prometon, and simazine were detected in the source and finished water of every system sampled. Deethylatrazine, a degradate, was detected in the source and finished water of every CWS but one. The triazine and chloroacetanilide herbicides were usually detected in the finished water after the treatment process, although for most treatment plants the concentrations were significantly less in the finished water. For other pesticides detected in source water—especially the organophosphate insecticides and other sulfur-containing pesticides (diazinon, chlorpyrifos, malathion, and metribuzin)—the treatment process either removed or degraded the pesticide completely.

Journal - American Water Works Association↗
USGS2000

Comparison of enzyme-linked immunosorbent assay and gas chromatography procedures for the detection of cyanazine and metolachlor in surface water samples

Enzyme-linked immunosorbent assay (ELISA) data from surface water reconnaissance were compared to data from samples analyzed by gas chromatography for the pesticide residues cyanazine (2-[[4-chloro-6-(ethylamino)-l,3,5-triazin-2-yl]amino]-2-methylpropanenitrile ) and metolachlor (2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl)acetamide). When ELISA analyses were duplicated, cyanazine and metolachlor detection was found to have highly reproducible results; adjusted R2s were 0.97 and 0.94, respectively. When ELISA results for cyanazine were regressed against gas chromatography results, the models effectively predicted cyanazine concentrations from ELISA analyses (adjusted R2s ranging from 0.76 to 0.81). The intercepts and slopes for these models were not different from 0 and 1, respectively. This indicates that cyanazine analysis by ELISA is expected to give the same results as analysis by gas chromatography. However, regressing ELISA analyses for metolachlor against gas chromatography data provided more variable results (adjusted R2s ranged from 0.67 to 0.94). Regression models for metolachlor analyses had two of three intercepts that were not different from 0. Slopes for all metolachlor regression models were significantly different from 1. This indicates that as metolachlor concentrations increase, ELISA will over- or under-estimate metolachlor concentration, depending on the method of comparison. ELISA can be effectively used to detect cyanazine and metolachlor in surface water samples. However, when detections of metolachlor have significant consequences or implications it may be necessary to use other analytical methods.

Journal of Agricultural and Food Chemistry↗
USGS1998

Relation of usage to the occurrence of cotton and rice herbicides in three streams of the Mississippi delta

During the 1995 growing season water samples were collected from three streams in the Mississippi delta and were analyzed for selected cotton and rice herbicides and metabolites. The purpose of the study was to relate the use of these herbicides to their occurrence in streams of the delta, to describe how the geochemistry of these herbicides affects their occurrence, and to report the occurrence of selected metabolites. The total concentration of eight herbicides and their metabolites exceeded 5 μg/L throughout most of the growing season with a median total of 15 μg/L. The order of occurrence was molinate > fluometuron > cyanazine > metolachlor > norflurazon > atrazine > prometryn > propanil. The distribution and duration of the total herbicide concentration found in this study are much different from that found in regional studies of herbicides in the U.S. Midwest. In the Midwest, the total herbicide concentration in surface water showed a sharp peak during the spring immediately after application of herbicides to crops, followed by a gradual decrease. In the Mississippi delta, the total herbicide concentration in surface water was more sustained, with multiple peaks due to different application times and postemergent applications to cotton and rice.

Environmental Science & Technology↗
USGS1998

Cotton herbicides in the surface waters of the Mississippi Alluvial Plain (the Delta)

The U.S. Geological Survey is conducting two studies to assess the environmental fate of herbicides used in cotton producing areas of the southeastern United States. The first study is evaluating surface-water quality on a regional basis and relating water quality to land use. The second study is examining the use of Best Management Practices to reduce off-site movement of agricultural chemicals in surface-water runoff. Maximum concentrations of the herbicides fluometuron and norflurazon in samples from surface water in edge-of-field studies were 23 and 7 micrograms per liter, respectively. Also, they were detected in the runoff of nearly every sampled storm for the 1997 water year at concentrations higher than 1.0 microgram per liter. Fluometuron and norflurazon were measured frequently in samples from rivers and streams in cotton producing areas, but the frequency of occurrence and the maximum concentrations were less than those in the edge-of-field studies.

Conference Paper↗
USGS1993

Surface-water and streambed-sediment quality of streams draining surface-mined land reclaimed with sewage sludge, Fulton County, Illinois, 1972-89

Sewage sludge has been used to reclaim surface- mined land in Fulton County, Ill. The sludge contains substantial concentrations of nutrients and significant concentrations of toxic organic compounds. Because of the concern of the fate of these toxins, the U.S. Geological Survey in cooperation with the Metropolitan Water Reclamation District of Greater Chicago began an analysis of historical data in 1989 to compare the quality of water and streambed sediments to determine whether the application of sludge is adversely affecting the quality of surface water. Trend analyses on surface-water-quality data suggest that sludge application is affecting the quality of water in Evelyn Branch in the form of increased concentrations of nitrite plus nitrate and kjeldahl nitrogen. However, the concentrations of these constituents in Evelyn Branch, the stream draining the sludge-application field, are small compared to the concentrations upstream from the project area. Analysis of the streambed-quality data indicates that, for the constituents measured, the application of sludge is not affecting the streambed quality in Evelyn Branch. Trend analyses of streambed constituents did not indicate any adverse effects that could be related to the application of sludge. However, the avail- able data are not adequate to determine if the quality of the streambed has been adversely affected by the sludge application. A refinement of the sampling scheme would be necessary to rule out the possibility of present and future adverse effects of sludge application on streambed quality.

Water-Resources Investigations Report↗
USGS1984

Water quality of the tidal Potomac River and Estuary; hydrologic data report supplement, 1979 through 1981 water years

This report is a companion report to the U.S. Geological Survey 1979, 1980, and 1981 Hydrologic Data Reports of the tidal Potomac River and Estuary. It contains values of biochemical oxygen demand and specific rate constants, incident light and light attenuation measurements; numbers of phytoplankton, fecal coliform and fecal streptococci, cross-sectional averages from field measurements of dissolved oxygen, pH, specific conductance , and temperature data; and cross-sectional averages of chlorophyll data. Sewage treatment plant loads are also included. (USGS)

Open-File Report↗
USGS1982

Water quality of the tidal Potomac River and estuary hydrologic data report, 1980 water year

This report contains data on the physical and chemical properties measured in the Tidal Potomac River and Estuary during the 1980 Water Year. Data were collected routinely at five stations, and periodically at 17 stations including three stations near the mouth of the Potomac River in Chesapeake Bay. Each of the five stations represent a cross section through which the transport of selected dissolved and suspended materials can be computed. The remaining stations represent locations at which data were collected for special synoptic studies such as salt water migration, and dissolved oxygen dynamics. Routinely, samples were analyzed for silica, nitrogen, phosphorus, chlorophyll-a, pheophytin, and suspended sediment. Additional samples were analyzed for organic carbon, calcium, manganese, magnesium, sodium, alkalinity, sulfate, iron, potassium, chloride, fluoride, seston, algal growth potential, adenosine triphosphate, nitrifying bacteria and dissolved-solids residue. In addition, solar radiation measurements and in-situ measurements of dissolved oxygen, specific conductance, pH, temperature, and Secchi disk transparency are reported. (USGS)

Open-File Report↗