Biological Engineering Commons^™

Enhancing The Adoption Of Soil Conservation Practices With Targeted Educational Programs, David P. Shelton, Elbert C. Dickey, Paul J. Jasa, David A. Biere

Biological Systems Engineering: Papers and Publications

Two independent, but closely related, grant funded educational programs have been developed and implemented to reduce soil erosion in selected areas of eastern Nebraska, U.S.A. Traditional extension programming methods as well as other more nontraditional approaches have been extensively used. In one program, encompassing 220,000 ha of cropland, annual soil erosion has been reduced by 2.5 Mt and annual fuel savings of 1.5 ML have been achieved through a reduction in the number of tillage operations. During a one-year period in the second project, more than 81,000 m of terraces were constructed, which resulted in an annual soil erosion reduction …

Surface Cover Provided By Selected Legumes, John E. Gilley, J. F. Power, P. J. Reznicek, S. C. Finkner

Biological Systems Engineering: Papers and Publications

The use of legumes in conservation tillage systems may yield several benefits including reduced erosion resulting from establishment of surface cover. The effectiveness in furnishing surface cover of 18 plant species seeded on three different dates was evaluated over an 11-month period. For several of the legume species, planting date significantly influenced maximum surface cover and the number of days required to reach maximum cover. For each of the planting dates, hairy vetch achieved maximum cover as rapidly as any other legume and maintained the greatest cover throughout the study period. Relationships for estimating legume surface cover from vegetative mass …

Determining Crop Residue Cover With Electronic Image Analysis, Elbert C. Dickey, David P. Shelton, G.E. Meyer, K.T. Fairbanks

Biological Systems Engineering: Papers and Publications

Crop residue management is one of the best and most efficient soil conservation methods available to farmers. Determinations of the percentage of the soil surface covered with crop residue are often needed for: soil conservation research; erosion control demonstrations; and maintaining compliance with federal, state, or local soil conservation regulations. A number of methods can be used to estimate residue cover, however, many have limitations. To help overcome some of these limitations, a technique, which uses readily-available microcomputer-related hardware and standard video camera equipment has been developed to estimate crop residue cover from photographic slides. This procedure is relatively rapid, …

Performance And Design Of Vegetative Filters For Feedlot Runoff Treatment, Elbert C. Dickey, D. H. Vanderholm

Biological Systems Engineering: Papers and Publications

Installation of a zero-discharge, runoff-control system is one method for solving potential water pollution problems from many feedlot operations. Even though the zero-discharge system is required by regulation in several states, this approach may be economically prohibitive for many small operations. An alternative is to install a vegetative filter system to adequately control the runoff so that violations of water quality standards will not occur during storm runoff. Vegetative filters are systems in which a vegetative area such as pasture, grassed waterways, or even cropland is used for treating feedlot runoff by settling, filtration, dilution, adsorption of pollutants and infiltration. …

The Cost Of Misapplication Of Herbicides, Robert Grisso, Elbert C. Dickey, Larry D. Schulze

Biological Systems Engineering: Papers and Publications

A field survey of 103 private herbicide applicators was conducted during the spring of 1986 in 12 central and eastern Nebraska counties. The results showed that only 30% of the cooperators were applying herbicides within 5% of their intended application rate. Twenty-six percent of the cooperators over-applied herbicides during a single application, with an average cost due to misapplication of $3.11/ha ($1.26/a). If these values were extended over Nebraska, $4.26 million are expended for extra herbicides which were not necessary. The average cost of over application was in excess of $570 per application. Forty-four percent of the cooperators under-applied herbicides …

Measurement Of Flow Components On Upland Areas Using Dye Dilution Techniques, S. C. Finkner, John E. Gilley

Biological Systems Engineering: Papers and Publications

Dye dilution techniques can be used to measure rill and interrill-to-rill flow rates on upland areas. Procedures and equations for making flow measurements are described along with equations for estimating interrill length and width. If measurements of interrill length and rill width are available, use of simplified flow equations is possible.

Water and dye continuity concepts were utilized to develop generalized interrill-to-rill flow relationships. Measurement of flow from interrill-to-rill areas requires information on the concentration and rate of dye injection, and flow rate and dye concentration on both rill and interrill areas at a downslope sampling location. Dye dilution techniques …

Comparison Of Bulk Density Beneath A Belt Track And Tire, Leonard L. Bashford, A. J. Jones, L. N. Mielke

Biological Systems Engineering: Papers and Publications

Wheel traffic is considered a major cause of soil compaction in production agriculture. Soil compaction depends on initial conditions, load, contact area and tire type and shape at the soil surface. The use of tractors equipped with tracks instead of tires has the potential of reducing soil compaction because of reduced surface contact pressure and difference in load distribution over a relatively long-narrow track. The introduction of a new agricultural tractor equipped with a rubber belt track permits a crawler tractor to compete with a large four-wheel drive tractor in both speed and mobility.
Soil bulk density was measured as …

A Timesaving Method For Labeling Figures, Tables And References, Randy Carlson

Biological Process Development Facility: Staff Publications

No matter how carefully an author outlines a manuscript, the figures, tables, and bibliographic citations are inevitably renumbered one or more times before the final draft. For example, the addition of a new reference to a late draft will sometimes entail the renumbering of all other references throughout the manuscript. A partial solution to this common technical problem in scientific writing is offered here. It is a refinement of an approach known to many scientists.

Biological Transformation And Detoxification Of 7,12-Dimethylbenzanthracene In Soil, K. Park, Ronald C. Sims, W. J. Doucette, J. E. Matthews

Biological Engineering Faculty Publications

Biological transformation and detoxification of 7,12-dimethylbenz(a)anathracene (DMBA) were studied in a nonacclimated sandy loam soil. Parent 14C DMBA biodegraded extensively (62% to 20%), accompanying an increase of metabolite 14C fraction (4% to 53%). Incorporation of DMBA into non extractable soil residue ,4C increased from 12 to 17%, but the increase was not statistically significant. DMBA was transformed into several metabolic products in the soil system, including 4-hydroxy-, 5-hydroxy-, and 10-hydroxy-DMBA and 7,12-dihydro 12-methyl-7-methylene-benz(a)anthracene-12-ol. High polarity transformation products of DMBA demonstrated a negative mu tagenic response with the Ames mutagenicity assay, strain TA 100, for both low and neutral pH soils. …

Human Health Effects Assays, Ronald C. Sims, J. L. Sims, R. R. Dupont

Biological Engineering Faculty Publications

Environmental health risk assessments based upon animal study results, epidemiology, quantitative structure activity relationships (QSARs), dose-response relationships, risk perception, and expert systems approaches, and the evaluation of mechanisms of carcinogenesis represent the focus for 1987. The term "biological risk assessment" was discussed by Clayson¹ to describe that part of risk assessment concerned with the relevance of specific animal results to the induction of human cancer. Guidelines for health assessment of suspect developmental toxicants addressed evaluation of data from animal testing studies.² Animal toxicity data on 200 chemicals and epidemiologic data on 30 chemicals was included within a data …

Fate And Transport Of Organics In Soil: Model Predictions And Experimental Results, B. D. Symons, Ronald C. Sims, W. J. Grenney

Biological Engineering Faculty Publications

Laboratory batch reactors were used to generate quantitative information about the fate of polynuclear aromatic hydrocarbon (PNA) compounds in soil systems. First-order degradation rates and equilibrium partition coefficients determined in laboratory studies were used in the Vadose Zone Interactive Processes (VIP) mathematical model to predict the fate and behavior of the PNA compounds as a function of time and soil depth. Predicted model results were compared with independent laboratory soil column studies for model validation. The VIP model provided a good approximation of the degradation and transport of the seven PNA compounds evaluated after 6 months of incubation in soil. …

Surface Cover From Corn Residue On Sandy Soils, R. Todd, Norman L. Klocke, Elbert C. Dickey, Dennis Bauer

Biological Systems Engineering: Papers and Publications

Corn residue left as surface cover after land preparation and planting by various combinations of tillage implements and surface planters, respectively, was measured on four research/ demonstration sites with sandy soils in Nebraska. Surface cover ranged from 51 to 80% for the no-till treatments to 14 to 53% for the twice-disked treatments. The wide range in cover was due to the amount of antecedent residues from the previous crop and the soil type which ranged from sandy loam to tine sands. Other tillage implements included a rolling cultivator, sweep-plow, and mulch-treader.

Correlation Of Starch Recovery With Assorted Quality Factors Of Four Corn Hybrids, Curtis L. Weller, Marvin R. Paulsen, Marvin P. Steinberg

Biological Systems Engineering: Papers and Publications

A laboratory wet-milling process was developed for use in determining starch recovery of yellow dent corn. The effects of harvest moisture and drying air temperature on starch recovery were investigated for four hybrids. A split split-plot experimental design was used to evaluate the effects. Starch recovery was not significantly different among the hybrids; however, it did decreases both harvest moisture and drying air temperature increased. Starch recovery was correlated with quantitative measures of assorted quality factors. Regression analysis found starch recovery to be a function of starch content, test weight, and ethanol-soluble protein.

Monitoring Natural Air Corn Drying—A Demonstration Project, Richard O. Pierce, Gary L. Zoubek

Biological Systems Engineering: Papers and Publications

A demonstration project is described where natural air corn drying performance was monitored weekly and drying results were printed in a local newspaper. The newspaper articles also gave management recommendations for the upcoming week. Similar demonstration projects can be conducted using the procedures described in this paper.

Calibration Accuracy Of Pesticide Application Equipment, Robert Grisso, E. J. Hewett, Elbert C. Dickey, R. D. Schnieder, E. W. Nelson

Biological Systems Engineering: Papers and Publications

Afield survey of 140 private and commercial pesticide applicators was conducted during the spring of 1986 in 12 counties of central and eastern Nebraska. The results showed that one out of every three cooperators was applying pesticides within ± 5% of their intended application rate. Results indicated that applicators have reduced application errors from that of a similar survey conducted in 1979. However, most errors still can be traced to incorrect calibration. Ninety-four percent of the cooperators used some type of calibration method. Two-thirds used the "Known Area" method. Those using a calibration method more than once a year had …

Electronic Image Analysis Of Crop Residue Cover On Soil, George E. Meyer, Anthony Stepanek, David P. Shelton, Elbert C. Dickey

Biological Systems Engineering: Papers and Publications

Classification procedures for using both black and white and color imaging systems were developed and tested for determination of percent residue cover on the soil surface from video and slide images. A spectral analysis of the image components was used for determining applicable wavelengths and filters. Color imagery provided an acceptable replacement for manual visual procedures. Black-and-white imagery also worked when appropriate blocking filters were used.

Nebraska's Modified-Open-Front Farrowing Houses Design And Operation, Gerald R. Bodman, Donald G. Levis, Duane E. Reese

Biological Systems Engineering: Papers and Publications

Two modified-open-front non-mechanically ventilated farrowing houses with creep boxes were operated over a two year period. Annual energy requirements were in the range of 10.6 to 10.9 cents per crate per day. No adverse effects on pig performance were realized. In most instances pig performance exceeded national standards of excellent performance—survival rates in excess of 90% and 21-day pig weights of 5.9 to 6.8 kg (13 to 15 lb). The study verified that another alternative is available to producers who do not want additional mechanical equipment to operate and maintain.

Size Distribution Of Sediment As Affected By Surface Residue And Slope Length, John E. Gilley, S. C. Finkner, G. E. Varvel

Biological Systems Engineering: Papers and Publications

Runoff samples for determination of size distribution of sediment were collected under simulated rainfall conditions at selected downslope distances on plots covered with sorghum and soybean residue at rates ranging from 0.00 to 6.73 t/ha . The effects of surface residue and slope length on size distribution of sediment were evaluated. Substantial movement of sediment in the form of aggregates was found for each of the residue treatments. Significant differences in size distribution of sediment occurred between residue treatments. For a given residue rate, differences in sediment size distribution were found between sorghum and soybean residue. Size distribution of sediment …

A Mathematical Model For The Fate Of Hazardous Substances In Soil: Model Description And Experimental Results, W. Greeney, C. Caupp, Ronald C. Sims

Biological Engineering Faculty Publications

A mathematical model (VIP) was developed and implemented for evaluating the fate of a hazardous substance in the unsaturated zone of the soil. The model simulates vadose zone processes including volatilization, degradation, adsorption/desorption, advection, and dispersion. Four physical phases in the vadose zone are considered including water, oil, soil grains, and soil-pore air (unsaturated pore space). The Vadose Zone Interactive Processes (VIP) model is appropriate for sites under RCRA and CERCLA (Superfund) categorization since site-specific soil-waste processes affecting transport of hazardous chemicals through the vadose zone are incorporated in the model. A RCRA land treatment system was chosen as the …

The Effect Of Temperature On Polycyclic Aromatic Hydrocarbon Persistence In An Unacclimated Agricultural Soil, M. P. Coover, Ronald C. Sims

Biological Engineering Faculty Publications

A laboratory study was conducted to investigate the effect of temperature on the persistence of polycyclic aromatic hydrocarbons (PAHs) incubated in an unacclimated agricultural sandy loam soil. Soil microcosms were spiked with 16 priority pollutant PAHs and placed in incubation chambers at 10, 20, and 30°C. Triplicate sets of microcosms at each temperature were periodically removed from incubation over the 240 day study period and solvent extracted. Concentrations of PAHs in the soil were determined by HPLC analysis of the extracts. Substantial loss of three-ring compounds was observed at all temperatures whereas there was very little apparent loss of five …

Conservation Tillage: Perceived And Actual Use, Elbert C. Dickey, Paul J. Jasa, Bryn J. Dolesh, Lisa A. Brown, S. Kay Rockwell

Biological Systems Engineering: Papers and Publications

A mail survey of farmers in Nebraska showed their perceived use of conservation tillage was about 55%. However, using the 30% residue cover criterion that the Conservation Tillage Information Center uses to define conservation tillage, a field survey of seven counties in 1984 showed that actual use of conservation tillage was less than 5%. Fewer than 20% of the producers surveyed had more than 20% residue cover remaining after tillage and planting. The field survey also showed disk tillage systems were used by almost 70% of the producers. The moldboard plow was used by only 15% of the producers, thus …

Slope Length And Surface Residue Influences On Runoff And Erosion, John E. Gilley, S. C. Finkner, G. E. Varvel

Biological Systems Engineering: Papers and Publications

Runoff rate, runoff velocity , sediment concentration and soil loss rate of rills or overland flow channels were measured at selected downslope distances on plots with varying rates of sorghum and soybean residue, runoff rate, runoff velocity and soil loss rate usually increased with downslope distance. In general, the presence of greater amounts of crop residue reduced sediment concentration and soil loss rate along the entire slope length. Substantial variations in runoff rate, runoff velocity, sediment concentration and soil loss rate were found with downslope distance on some residue treatments.

The Rate Of Benzo[A]Pyrene Apparent Loss In A Natural And Manure Amended Clay Loam Soil, M. P. Coover, Ronald C. Sims

Biological Engineering Faculty Publications

A study was conducted to evaluate the rate of Benzo[a]pyrene apparent loss from a previously uncontaminated agricultural clay loam soil and to determine the effect of cow manure, as organic substrate amendment, on B[a]P apparent loss. Soil microcosms were spiked with 10 μg/g B[a]P and incubated at 20°C. Triplicate sets of microcosms were periodically removed from incubation and solvent extracted. Concentrations of B[a]P in the soil were determined by HPLC analysis of the extracts. Under the conditions of this study manure was an ineffective amendment for increasing the rate of B[a]P apparent loss in the Durant clay loam soil. In …

Slot Injection Of Herbicides, Paul J. Jasa, Elbert C. Dickey, Thomas R. Peterson

Biological Systems Engineering: Papers and Publications

Injection of thiocarbamate herbicides into a slot created by a coulter was evaluated during a 3-year study in southeastern Nebraska. Control of shattercane, the dominant weed, with the slot injector was similar to conventional double disk incorporation. In both tilled and untilled surface conditions, the slot injector placed the herbicide into the soil with minimal disturbance of the soil and residue. Herbicides which are normally broadcast applied were band applied, reducing chemical costs by two-thirds.

Runoff And Erosion As Affected By Sorghum And Soybean Residue, John E. Gilley, S. C. Finkner, G. E. Varvel

Biological Systems Engineering: Papers and Publications

A rainfall simulator was used to measure the effects of varying rates of sorghum and soybean residue on runoff and erosion. In general, increased surface cover caused reduced runoff, sediment concentration and soil loss. Substantial reductions in erosion resulted from the use of small amounts of crop residue. Regression equations were obtained which related surface cover to residue mass. Equations describing relative runoff, sediment concentration and soil loss as a function of surface cover were also developed. Runoff, sediment concentration and soil loss were all found to be highly correlated to surface cover.

Size Distribution Of Sediment As Affected By Corn Residue, John E. Gilley, S. C. Finkner, R. G. Spomer, L. N. Mielke

Biological Systems Engineering: Papers and Publications

Size distribution of sediment was measured under simulated rainfall conditions at selected downslope distances on plots with corn residue rates ranging from 0.00 to 6.73 t/ha. The formation of rills caused increases in the percentage of larger sized sediment material. Greater surface cover usually resulted in an increase in the percentage of smaller sized sediment.

Considerable variation in the size of sediment from both rill and interrill areas was found with downslope distance. On interrill regions, the presence of residue served to reduce sediment size along the entire plot length. Transport of aggregated sediment occurred on each of the residue …

Tillage Systems For Row Crop Production, Elbert C. Dickey, Paul J. Jasa, Alice J. Jones, David P. Shelton

Biological Systems Engineering: Papers and Publications

Selecting the tillage system best suited to a particular farming situation is an important management decision. Formerly, the traditional system was a moldboard plow operation followed by several secondary tillage operations before planting. This system can be appropriate for poorly drained soils having little or no slope and low erosion potential. However, plowing has several disadvantages . The potential for soil erosion is high on sloping lands, and labor and fuel requirements can be substantially higher than with other tillage and planting systems.

Today, conservation tillage systems are used to reduce preplant tillage operations, thus reducing soil erosion and moisture …

Review And Evaluation Of Current Design And Management Practices For Land Treatment Units Receiving Petroleum Wastes, J. P. Martin, Ronald C. Sims, J. Matthews

Biological Engineering Faculty Publications

Land treatment is categorized in the Resource Conservation and Recovery Act of 1976 (RCRA) as one of the land disposal options for managing hazardous wastes. Land treatment relies on detoxification, degradation, and immobilization of hazardous waste constituents within the defined treatment zone to ensure protection of surface water, groundwater, and air. Under the authority of Subtitle C of RCRA, the U.S. Environmental Protection Agency has promulgated regulations governing the treatment of hazardous wastes in land treatment units (40 CRF, Part 264, Subpart M, July, 1982).

This paper describes the land treatment practices used by petroleum waste land treatment facilities in …

Sediment And Dye Concentration Effects On Fluorescence, S. C. Finkner, John E. Gilley

Biological Systems Engineering: Papers and Publications

Because of the relatively large sediment concentrations sometimes found on upland regions, adsorption of fluorescent dye onto sediment may be of concern. A laboratory study was conducted to identify the effects of sediment and dye concentration on adsorption. Sediment and dye concentration were both found to significantly affect adsorptive dye loss of rhodamine WT and sulpho rhodamine B.
Regression equations were developed which related dye adsorption to sediment and dye concentration. For a particular soil and dye material, regression equations may be used to correct for adsorptive dye loss. Sulpho rhodamine B is recommended as the dye of choice for …

Runoff And Erosion As Affected By Corn Residue: Prt Ii: Rill And Interill Components, John E. Gilley, S. C. Finkner, R. G. Spomer, L. N. Mielke

Biological Systems Engineering: Papers and Publications

Hydraulic and soil loss variables were measured under simulated rainfall conditions at selected downslope distances on plots with corn residue rates ranging from 0.0 to 6.7 t/ha. Application of corn residue produced substantial reductions in runoff rate, runoff velocity, sediment concentration and soil loss rate along the entire slope length. On those plots subject to rilling, runoff rate, sediment concentration and soil loss rate usually increased with downslope distance.

Rill and interrill sediment concentration and soil loss rate were also measured at selected slope lengths. lnterrill sediment concentration changed little with downslope distance while greater interrill soil loss rates were …