Life Sciences Commons^™

Formulation Enhanced Transport Of A Soil Applied Herbicide, V. P. Evangelou, Louis M. Mcdonald, Sandra Prima

KWRRI Research Reports

Because pesticides are applied as formulated particles and the affinity of the active ingredient for the formulation is higher than for the bulk water, we hypothesized that a formulation complex could affect active ingredient transport. Our objectives were to investigate the nature and extent of surfactant-atrazine-clay/oxide surface interactions. When atrazine and an anionic surfactant were dried onto plain or Fe-coated sand and leached, atrazine concentrations in the initial leachate were lower in the Fe-coated sand treatment. This was likely due to an electrostatic attraction between the sand and surfactant. When a nonionic surfactant was used, atrazine concentration in the initial …

Use Of Riparian Vegetated Filter Strips To Reduce Nitrate And Fecal Contamination In Surface Water, Mark S. Coyne, Robert L. Blevins, Rebecca A. Gilfillen

KWRRI Research Reports

This research assessed fecal bacteria trapping in surface runoff by grass filters and their potential to enhance NO₃^- removal via denitrification. Grass filter strips 9.0 m long trapped over 99% of the soil in surface runoff in 1992. Fecal coliform removal was less than 75%. In 1993, 9.0 and 4.5 m grass filter strips trapped 99 and 95% of the sediment, respectively. Fecal coliform trapping efficiency was 90% in 9.0 m grass filters and 75% in 4.5 m filters. Fecal streptococci trapping efficiency was 77% in 9.0 m grass filters and only 56% in 4.5 m filters. Fecal …

Potential Of Surface Water Contamination From Three Triazine Herbicides, William W. Witt, Kip W. Sander

KWRRI Research Reports

The movement of atrazine, cyanazine, and simazine from the site of application was monitored under conventional, reduced, and no-tillage conditions. Less water and soil was lost from the no-tillage and reduced tillage conditions. Conventional tillage conditions had about 66,000 L/ha runoff in 1986-87 and about 123,000 L/ha runoff in 1987-88. Seasonal rainfall was 885 mm in 1986-87 and 397 mm in 1987-88. The rainfall intensity was greater during the first two events in 1987 than the corresponding events in 1986. The first rainfall event in 1986 accounted for 91, 89, and 78% of the total seasonal loss of atrazine, cyanazine, …

Abatement Of Nitrate Pollution In Groundwater And Surface Runoff From Cropland Using Legume Cover Crops With No-Till Corn, M. Scott Smith, Jac J. Varco

KWRRI Research Reports

Agricultural practices can have a significant impact on water quality. The effects of leguminous winter cover crops on leaching of NO^-₃; from soil have been investigated in this project. Legume cover crops, by fixation of atmospheric N, can reduce the amount of fertilizer N required to produce summer grain crops. The methods initially used to evaluate cover crop effects on No; transport included suction probe lysimeters and measurement of NO^-₃; in soil samples collected to a depth of 90 cm. These measurements demonstrated extreme spatial variability in NO^-₃; distribution and water …

Effects Of Surface Application Of Dairy Manure On The Infiltration Rate And Quality Of Surface Runoff, Joseph L. Taraba, I. J. Ross, John D. Bottom, Bill J. Barfield

KWRRI Research Reports

Dairy manure was surface spread on 12 ft x 12 ft plots on an established fescue pasture in the summer and fall of 1981 and 1982. The soil was a Maury silt loam. A simulated rainfall was applied to plots to test the effects of nitrogen loading rate (75, 150, and 300 #N/acre) time delay between manure application and the simulated rainfall events (0, 3, 6, 24, 48, 96 hours and a 120 hour test repeated on 0 hr plot with 300 #N/acre), and type manure (semi-solid - 1981 and liquid - 1982) on the concentrations of pollutants in the …

Influence Of Nitrogen Fertilization On The Quality And Quantity Of Streamflow From A Forested Watershed, George B. Coltharp, Michael T. Shearer, Everett P. Springer, Robert F. Wittwer

KWRRI Research Reports

This project was designed to determine the effects of nitrogen fertilization on the quality and quantity of streamflow eminating from an eastern hardwood forest watershed. A 40.67 ha watershed, located in mountainous eastern Kentucky, was aerially fertilized in late April 1975. The forest stand was principally oak, hickory, and yellow poplar, 50 - 55 years of age and in a relatively undisturbed condition. A helicopter applied anunonium nitrate at a rate of 504 kg/ha. Because a large part of applied nitrogen fertilizer ends up in the highly mobile nitrate nitrogen.form, this is the principal ion monitored in this study. No …

Part I - Controlling The Soil Moisture Environment Of Transpiring Plants, Part Ii - Prediction Of Leaf Temperature Under Natural Atmospheric Conditions, Charles T. Haan, Billy J. Barfield, Robert Edling

KWRRI Research Reports

Part I

A technique for controlling the soil moisture potential in the root zone of transpiring plants was developed. The method uses the principles of unsaturated flow through a porous media to develop the desired moisture potential. In the case of non-steady state transpiration, the maximum possible fluctuation in the soil moisture potential can be determined by the techniques presented.

Part II

Two implicit leaf temperature prediction equations were derived from the energy balance approach. The equations define sensible and latent heat transfer from a plant population as a two step process:

1. Transfer between the plant leaf and the canopy …