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•CANADIANAGRICULTURAL

ENGINEERING

The Journal of the Canadian Society of Agricultural EngineeringLa Revue de la Societe Canadienne du Genie Rural

CAE 35(3) 157-236(1993)CN ISSN 0045-432X

Soil and Water

PRELIMINARY ESTIMATES OF THE ERODIBILITY OF TEN QUEBEC EASTERNTOWNSHIPS SOIL SERIES

F. Salehi, A.R. Pesant, A. Berard and R. Lagace 157

INFILTRATION UNDER NO-TILL AND CONVENTIONAL TILLAGE SYSTEMS INSASKATCHEWAN 165

C.P. Maule and W.B. Reed

EFFECTS OF ASUBSURFACE INTERCEPTION DRAINAGE SYSTEM ON SOILMOISTURE REGIME IN ASALINE-SEEP AREA 175

G.J. Beke, D.P. Graham and T. Entz

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Volume 35

C. LAGUE

(Power & Machinery)Departement de genie ruralUniversite LavalSainte-Foy, Quebec G1K7P4

J.J.R. FEDDES

(Structures & Environment)Department of Animal ScienceUniversity of AlbertaEdmonton, Alberta T6G 2H1

CANADIAN AGRICULTURAL ENGINEERING1993

July/August/SeptemberVolume 35, Number 3

EDITOR

n.b. MclaughlinCentre for Land and Biological Research

Research Branch, Agriculture CanadaBuilding 74, CEF

Ottawa, Ontario K1A0C6

ASSOCIATE EDITORS

S.F. Barrington(Waste Management)Department of Agricultural EngineeringMacdonald College of McGill UniversitySte. Anne de Bellevue, Quebec H9X 3V9

J. MILLETTE

(Soil & Water)Centre for Land and Biological ResearchResearch Branch, Agriculture Canada3039 K.W. Neatby Building, CEFOttawa, Ontario K1A0C6

D.S. JAYAS

(Food Engineering/Energy & Procesing)Department of Agricultural EngineeringUniversity of ManilobaWinnipeg, Manitoba R3T 2N2

L. GAUTHIER

(Information & Computer Technologies)Departement de genie ruralUniversite LavalSainte-Foy, Quebec G1K7P4

President

CSAE COUNCIL 1992-93

D.I. NORUM

Department of Agricultural andBioresource Engineering

University of SaskatchewanSaskatoon, Saskatchewan S7N 0W0

Secret/inManiloba

D.E. DARBY

Alberta AgricultureAgriculture CentreLethbridge, Alberta TIJ4C7

P. SAVOIE

Agriculture Canadapepartememt de genie ruralUniversite LavalSainte-Foy, Quebec G1K7P4J.K. HIGGINSNova Scotia Department of

Agriculture & MarketingPO Box 550 STruro, Nova Scotia B2N 5E3

Agriculture CanadaOttawa, Ontario K1A0C6

On^StryofAS^S'^-^Vmeland, Ontario LOR 2E0

Past President

R. MacDONALD14 Univeristy Ave. W.Guelph, Ontario NIG INI

REGIONAL DIRECTORS

am, , r ,South Fraser WayAbbotsford, British Columbia V2S 2C5

D.R.ST. GEORGEManitoba HydroP.O. Box 250Brandon, Manitoba R7A 5Y8S. NEGI

School ofEngineeringUniversity ofGuelphGuelph, Ontario NIG 2WI

J. GALLICHANDDepartement de genie ruralUniversite LavalSainte-Foy, Quebec G1K 7P4J-L. DAIGLELand Resources BranchP.aBBr6f»0kDePar,mem"fA8ri-''ureFredericton, New Brunswick E3B5H1

President-Elect.

L.J. RING

Raymond, Alberta TOK 2S0G.R. BAYNE19 Windfield RoadKegina, Saskatchewan S4V 0E6

Treasurer

Alberta

Saskatchewan

Ontaru

Quebec

Atlantic

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.nCTDirTo OF papfrs PRESENTED BY CANADIAN AUTHORS AT THE JOINT AMERICAN SOCIETY OFJS^™^E^SSS^SiA SOCIETY OF AGRICULTURAL ENGINEERING CONFERENCE,^C^o^of'pTpts^re avaikble for US $3.50 each for CSAE/ASAE members ($5.00 for non-members) plus $2.50 handling perorder from American Society of Agricultural Engineers, 2950 Niles Rd., St. Joseph, MI 49085-9659.

93-1002. SENSOR FOR MEASURING LOW VOLUMESPRAY DEPOSITR.C. Maze and K.T. Parekh, Alberta Farm Machinery Research Centre, Lethbridge, AB.

A spray deposit sensor, circuit and dataacquisition systemwas developed. The sensor provides a voltage output proportional to the number of spray drops deposited on the sensor.Spray deposits ranging from 1 to 10 (il were measured. Theability to accurately measure deposit volume was evaluated forvarious nozzles over a range of pressures. Constant line spacing sensors and variable line spacing sensors were used todetermine spray volumes and droplet size ranges. The sensorsand data acquisition system provided quick, accurate results ofspray deposits under 10 |xl.

93-1003. PREDICTION OF DROPLET TRAJECTORIESFROM AIR-BLAST SPRAYERS

M.M. Sidahmed and R.B. Brown, School of Engineering,University of Guelph, Guelph, ON.

A study of an air-blast sprayer designed for forestry application of herbicides is described. A computational fluiddynamics program was used to model the jet characteristicsand predict spray droplet trajectories with the sprayer. Thesimulation was validated with data collected from a smaller

centrifugal fan.

93-1008. AGRICULTURAL VEHICLE GUIDANCE SEN

SOR

N.D. Klassen, R.J. Wilson and J.N. Wilson, College of Engineering, University of Saskatchewan, Saskatoon, SK.

The development of a sensor, consisting of a video cameraand image processing system, to detect the location of thedemarcation line between tilled-and-untilled soil and cut-and-

standing crop is presented. Hardware and softwaredevelopment to achieve real-time operation under a variety ofcrop, soil and ambient lighting conditions is described.

93-1011. FEEDRATE MEASUREMENT IN COMBINE

HARVESTERS

N.D. Klassen, R.J. Wilson and J.N. Wilson, College of Engineering, University of Saskatchewan, Saskatoon, SK.

The results of an investigation, using electrical capacitancesensing techniques for measuring feedrate in combine harvesters, are presented. The effects of material density, thicknessand moisture content on two sensor configurations were investigated.

93-1029. SOIL COMPACTION REDUCTION BY OVER

SIZE TIRES AND MULTIAXLES RUNNING GEAR

Y. Bedard, S. Tessier, C. Lague and L. Chi, Departement degenie rural, Universite Laval, Quebec, PQ.

We studied the effects of one pass of heavy liquid manurespreaders upon compaction of a clay soil. Five levels of vertical load (from 96.5 to 218 kN), two types of running gears(two- and three-axles) and two types of tires were used in the

experiment. Results show that compaction is limited to theupper 250 mm of the soil profile. Reducing the unit load peraxle by using multiples axles running gears allows todecreasethe risks of excessive soil compaction. It was however foundthat no running gear system can limit compaction within acceptable limits for total vertical load exceeding 154 kN.

93-1031. SLIP MEASUREMENT USING DUAL RADARGUNS

R.J. Turner, Alberta Farm MachineryResearchCentre,Lethbridge, AB.

Tire slip at operation load is an important parameterwhenoptimizing the performance of a tractor. However, accuratemeasurement of slip under working conditions is difficult inmost farm situations. Many new tractors and most older onesare not equipped with slip indicators and often "on the farm"tractor slip is either measured manually and crudelyor simplyestimated. This paper describes a method of obtaining accurateslip readings on a tractor through the use of two radar guns.The system is universal, portable, quickly attached and requires no modification to the tractor.

93-1041. EXPERIENCES WITH FORCED-AIR PRE-

COOLING OF SWEET CORN

H.W. Fraser, Ontario Ministry of Agriculture & Food,Vineland Station, ON; and Y. Lee, School of Engineering,University of Guelph, Guelph, ON.

An on-farm forced-air precooler was built and 1/2 CoolingTimes were found for sweet corn under different conditions

including room cooling and hydrocooling. Forced-air precool-ing was demonstrated to be an effective alternative forremoving field heat quickly after harvest.

93-1051. TESTING THE DYNAMIC RESPONSE OF A

DIGITAL CONTROL SYSTEM FOR VARIABLE RATE

NITROGEN FERTILIZATION

Y. Li, Mechanical Engineering Department; R.L. Kushwahaand G.C. Zoerb, Agricultural and Bioresource EngineeringDepartment, University of Saskatchewan, Saskatoon, SK.

In this study, a prototype digital control system for variablerate nitrogen fertilization was assembled in the laboratory. Thecontrol software was developed to test the dynamic responseof different controllers. The dynamic response obtained areanalyzed to verify the conclusions from the dynamic responsesimulation. It was found that the steady state offset error of thetested dynamic response is close to that of the simulated dynamic response. However, the settling time and overshoot ofthe tested dynamic response are different from that of thesimulated dynamic response. The test results showed that thePole-placement controller has the lowest steady state offsetand is more resistant to large torque disturbance than othercontrollers.

CANADIAN AGRICULTURAL ENGINEERING Vol. 35, No. 3, JULY/AUGUST/SEPTEMBER 1993 229

93-1057. DROPLET SPREADING AND PENETRATIONOF AQUEOUS PESTICIDE DROPLETS IN CUTICU-LAR WAX OF NATURAL AND SIMULATED FIRFOLIAGE

A.Sundaram, Forestry Canada, Forest Pest Management Institute, Sault Ste. Marie, ON.

Aqueous formulation of Bacillus thuringiensis var. kur-Staki, (BTK) were sprayed in a laboratory chamber overbalsam fir branches, andaluminum fir branches (foliar simulator) with and without a coating of the cuticular wax extractedfrom fir foliage. Drop size spectra, drops/cm2, and spray massdeposit/cm were assessed. Both natural foliage and foliarsimulator received similar drop sizes, drops/cm2 and deposits,butthe latter twoparameters were higher on thefoliar simulatorthat hadno wax coating. Theinvestigation provided a newmethod to determine the actualdrop sizesdeposited on a foliarsimulator. Thesimulator not onlyhad similar sizeand shape,butalsothesamesurface characteristics, as thenatural foliage.

93-1070. PRESCRIPTION MAPS FOR HERBICIDESPRAYER CONTROL

J.P. Steckler and R.B. Brown, School of Engineering, University of Guelph, Guelph, ON.

Weed maps of no-till corn fields were produced by imageanalysis of aerial conventional colour and colour-infraredpositive transparencies. They were imported into a GeographicInformation System (GIS) and subdivided into independentunits for spatially-variable herbicide application. Each subunitwas submitted to an external herbicide application decisionmodel. The resulting prescription maps can be used to controla field sprayer to significantly reduce herbicide use.

93-1079. EVALUATION OF VINEYARD SPRAYERS

FOR COVERAGE AND DRIFT

W. McFadden-Smith, Horticultural Research Institute of Ontario, Vineland Station, ON; and K. Ker and G. Walker,Ontario Ministry of Agriculture and Food, Vineland Station,ON.

Fow vineyard sprayers were evaluated for coverage anddrift. Air-blast sprayers gave superior coverage of upper andlower leaf surfaces and fruit compared to low volume or hydraulic recycling sprayers. Off-target drift was greater at 2 mandgroundlevel from the air-blast than the other sprayers 2.54m downwind from the target but not at greater distances.

93-1088. A CONE PENETROMETER EQUIPPED WITHA SINGLE CHIP MICROCOMPUTERJ. Shen and R.L. Kushwaha, Agricultural & BioresourceEngineeringDepartment, Universityof Saskatchewan,Saskatoon, SK.

Quick and accurate determination of soil strength values hasa great significancein agricultural,civil and military engineering applications. A small manually operated conepenetrometer equipped with single chip microcomputer wasdeveloped to quickly measure cone index, cohesion, 'c' andangle of internal friction, of soils.

93-1090. WEAR AND DRAFT OF CULTIVATORSWEEPS WITH HARDENED EDGESJ. Zhang and R.L. Kushwaha, Department of Agriculturaland Bioresource Engineering, University of Saskatchewan,

230

Saskatoon, SK.

Wear characteristics ofseveral cultivator sweeps were studied using the newly developed abrasive tester. Comparisonswere made between the regular sweep and hardfaced edgesweeps. The hardfaced sweeps proved to have better wearresistance in performance. The wear characteristics were alsoevaluated by measuring the profile change of the tillage toolsusing image analysis. The energy consumption of new andworn sweeps was evaluated in the conventional soil bin.

93-2001. AUTOMATED METHOD FOR FINDING THECAPILLARY PRESSURE-SATURATION RELATIONSHIP

R. Sri Ranjan, T. Karthigesu and G.E. Laliberte, Department of Agricultural Engineering, University of Manitoba,Winnipeg, MB.

The relationship between capillary pressure and saturationfor soil samples is a necessary input for understanding thehydraulic behaviour of soils. Traditional methods of determining this relationship are tediousand are subject to errors basedon the skill of the person making the measurements. Traditionally, each pair of measurements is taken after an equilibrationtime which is based on prior experience. The computer-controlled automated technique uses a non-destructive method tomonitor the capillary pressure and saturation and, therefore,eliminates the guess work out of the time to reach equilibrium.This method will be helpful in obtaining data from severalsamples in a consistent manner. The method has potential forwider use by computer modellers doing environmental remediation work who need better field data representative of thesite.

93-2002. NON-DARCY FLOW PHENOMENA IN SAND-

BENTONITE MIXTURES

T. Karthigesu and R. Sri Ranjan, Department of AgriculturalEngineering, University of Manitoba, Winnipeg, MB.

Darcy's law has been used to describe the saturated fluxversus hydraulic gradient relationship universally. However infine grained materials the saturated flow under gradients lessthan 0.2 have been found to be non-linear. Therefore, thevalidity of using Darcy's law to describe the flow at these lowgradients will result in over estimation of flux. Fine grainedmaterials are used as barriers for the containment of hazardous

waste. A measurement technique that is capable of accuratelydetermining very low flux is presented. A simplified flowmodel describes the non-linear flow behaviour.

93-2003. AUTOMATED TECHNIQUE FOR FINDINGTHE PERMEABILITY-CAPILLARY PRESSURE RE

LATIONSHIP

R. Sri Ranjan, T. Karthigesu and G.E. Laliberte, Department of Agricultural Engineering, University of Manitoba,Winnipeg, MB.

The relationship between relative permeability and capillary pressure of soil core samples is a necessary input formodelling the unsaturated hydraulic behaviour of the subsurface environment. Traditional methods for determining thisrelationship require an equilibration time which is based onprior experience. The computer controlled automated technique uses a non-destructive method to monitor the capillarypressure and the flow rate through the core sample and there-

ABSTRACTS

foreeliminates theguess work outof the timeto reach equilibrium. This method will be helpful in obtaining data fromseveral samples in a consistent manner. This method has potential for wider use by computer modellers, working onenvironmental rernediation projects, to get better field datarepresentative of the site. It could also be used as a teachingand demonstration tool in the laboratory.

93-2004. STOCHASTIC ANALYSIS OF INFILTRATIONRATES OBTAINED WITH RAINFALL SIMULATORR. Gupta, R.P. Rudra andW.T. Dickinson, School of Engineering, University of Guelph, Guelph, ON; N. Patni, ARC,Agriculture Canada, Ottawa, ON; and G.J. Wall, LRC, Agriculture Canada, Guelph, ON.

Rainfall simulation experiments were conducted at Agriculture Canada farm, Ottawa. Analysis of data indicates thatinfiltration rates vary substantially in spatial domain duringsummer and spring season. Further analysis of data revealedthat the spatial structure of these variations can be describedby a stochastic model involving deterministic and stochasticcomponents.

93-2006. NUMERICAL SIMULATION OF NON-ISOTHERMAL MULTICOMPONENT REACTIVESOLUTE TRANSPORT IN UNSATURATED/SATU-RATED SOILS

G. Wu and S. Chieng, Department of Bio-Resource Engineering, University of British Columbia,Vancouver, BC.

A computer program has been developed to simulate thesimultaneous processes of water flow, heat transfer and transport of a multicomponent reactive solute inunsaturated/saturated soils. The chemical reactions that can bemodeled include aqueous complexation, acid base reaction,redox ion exchange, and precipitation-dissolution.

93-2010. REDUCING MANURE OUTPUT TO STREAMSFROM SUBSURFACE DRAINAGE SYSTEMS

J.E. McLellan, R.J. Fleming and S.H. Bradshaw, Agricultural Engineering Section, Centralia College, Huron Park, ON.

An experiment in controlled drainage was performed inorder to assess the feasibility of using this technique to attenuate the loading of nutrients and bacteria to surface water bodiesafter application of liquid manure on farmland. A flat fieldunderlain by tight clay soil was divided into two equal sections. Header drains, with lateral subsurface drains feedinginto them, were fitted with observation wells for monitoringflow and water quality. Prior to the application of liquid pigmanure on the land, drainage under one of the sections wasblocked by a stand pipe and cap located in the observationwell. After 7 days, the blocked drain was released. Comparisonof the total loading of nitrate, chloride, ammonium, faecalcoliform, faecal streptococci, and E. coli for the two sectionsindicated that blocking the flow of subsurface drainage waterduring manure application resulted in an appreciable reductionof ammonium and bacteria.

93-2056. EFFECT OF IRRIGATION FREQUENCY ANDAPPLICATION VOLUME ON SOIL MOISTURE DIS

TRIBUTION FROM TRICKLE IRRIGATION

EMITTERS

P. Parchomchuk and G. Owen, Agriculture Canada Research

Station, Summerland, BC.Growth of alfalfa along dripper lines was used to measure

the width of canopy which could be irrigated with differentfrequencies andvolumes of applied water. Irrigation frequencies ranging from 3 times perdayto once every 3 days didnotaffect irrigated width. Increasing the volume of applied watercaused highly significant increases in irrigated width but themaximum practical width that can be irrigated is limited bydecreasing application efficiency as applied volume increases.

93-2065. HYDRAULIC CONDUCTIVITY DETERMINATION FOR DRAINAGE MODELINGR.P. Rudra, W.T. Dickinson and R.K. Gupta, School ofEngineering, Universityof Guelph, Guelph, ON.

Saturated hydraulic conductivity determined by ring infil-trometer, rainfall simulator, the Guelph Permeameter and theGuelph Infiltrometer during summer, fall and spring seasonswere compared with the best calibrated model obtained fromDRAINMOD. Analysis of the measured and calibrated saturated hydraulic conductivity values indicated that none of themodels gave hydraulic conductivity consistently suitable forcontinuous drainage modelling. The calibrated hydraulic conductivity varies with climatic characteristics.

93-2081. TILLAGE AND WATERTABLE MANAGEMENT TO ABATE HERBICIDE AND NITRATE LOSSIN SURFACE RUNOFF AND TILE DRAINAGE WATERC.S. Tan, J.D. Gaynor, C.F. Drury and T.W. Welacky,Agriculture Canada, Harrow, ON.

Corn management practices, incorporating annual ryegrassintercrop, conservation tillage, and watertable managementwere evaluated to reduce herbicide and nitrate losses throuehsurface runoff and tile drainage. Atrazine (1.1 ke«ha' ),metribuzin (0.5 kg»ha_1) and metolachlor (1.68 kg*ha" ) wereappliedpreemergence in a band over the seededrow to reduceherbicide input 50%. The soil saver with intercrop had thelowest losses of the three herbicides. The intercrop treatmentreducedaqueoustransportmost from surfacerunoff thanfromtile drainage. Watertable control increased aqueous herbicidetransport by surface runoff but decreased loss through tiledrainage so that total loss remained unchanged. Watertablecontrol systems have dramatically reduced the nitrate concentration in tile drainage water by 33-36% and nitrate loss by37% in the fall/winter period and by 66% in the spring/summerseason. Intercropping with annual ryegrass reduced nitrate lossin surface runoff especially with the watertable control system.Therefore watertable control with intercrop is the best management system to abate nitrate contamination of surface anddrainage waters.

93-2082. THE EFFECTS OF TILLAGE AND CROPRESIDUES ON WATER AND NITRATE MOVEMENT

IN SOIL COLUMNS

V.K. Serein and C.A. Madramootoo, Department of Agricultural Engineering, Macdonald Campus of McGill University,Ste-Anne de Bellevue, PQ.

Laboratory soil columns were used to study the effects ofthree tillage systems and two corn residue levels on nitrate andwater movement through a sandy loam soil. Rainfall wasartificially applied to the columns. Moisture content was measured and leachate sampled at 100, 200, 400, and 600 mm

CANADIAN AGRICULTURAL ENGINEERING Vol. 35, No. 3, JULY/AUGUST/SEPTEMBER 1993 231

depths. Preliminary results indicate that while conservationand conventional tillage allowed immediate nitrate movementinto the top 200 mmof the soil profile, deep leaching did notoccur. Ontheotherhand, thenotill treatment exhibited deeperleaching although the initial rate of movement was lower.

93-2090. LS FACTOR DERIVED FROM A GRID DIGITAL ELEVATION MODEL

S.M. Huddle, W.T. Dickinson and R.P. Rudra, School ofEngineering, University of Guelph, Guelph, ON.

This paper explores several characteristics of cellular drainage networks derived from regular grid DEM's to estimateslope length andslopegradient for the LSfactor. Thecompari-son of computer-generated and human-generatedrepresentations showed that both deterministic and stochasticcellular drainage algorithms generate drainage networks withrepresentation artifacts that hinder their use with distributedsoil loss modelling. For determination of site specific hydro-logic conditions, cellular networks poorly representedintra-area drainage relationships.

93-2097. SNOWMELT EROSIVITY OF THE CANADIANPRAIRIES

C.P. Maule, Agricultural and Bioresource Engineering Department, University of Saskatchewan, Saskatoon, SK; M.Black, Agriculture Canada, Regina, SK; and D. Chanasyk,Department of SoilScience,Universityof Alberta,Edmonton,AB.

Runoff erosivity maps for snowmelt for the agriculturalregions of the Canadian Prairies are presented. Erosivity values for stubble and fallow conditions from 80 climatic stationswere estimated using 30 years of daily temperature, precipitation, and evaporation data with a soil water budget model(Versatile Soil Moisture Budget, VSMB). Average erosivityvalues were low, relative to rain values, ranging from 8 to 20MJ»mm*ha" •h" for the spring snowmelt period. The erosivity values are to be used with RESLE which will accommodatesoil erodibility changes due to freeze-thaw conditions.

93-2113. NO-TILL EFFECTS UPON SOIL WATER

PROPERTIES

C.P. Maule and W.B. Reed, Agricultural and BioresourceEngineering Department, University of Saskatchewan, Saskatoon, SK.

No-till systems are effective in reducing soil erosion; however their effects upon soil moisture conservation is not fullyknown. This study evaluated soil water retention and transmission properties of three different tillage systems, no-till (threefields of different ages), conventional tillage under fallow, andconservation tillage. Infiltration at 60 minutes, macroporosity,and pore continuity were greater for the no-till system andincreased with number of years of no-till. Organic mattercontent as opposed to bulk density provided the best explanation to changes in soil water properties.

93-2123. A FIELD DRAINAGE EXPERIMENT TO RE

DUCE NITRATE POLLUTION

C.A. Madramootoo, R. Tait and R.S. Broughton, Department of Agricultural Engineering, Macdonald Campus ofMcGill University, Ste-Anne-de-Bellevue, PQ.

A large scale field experiment, covering 4.5 ha, was established in Quebec, Canada, to assess the impacts of drainage,

232

watertable management, cropping systems andfertilizer practices on water quality. Eight treatments are replicated threetimes in a randomized complete blockdesign. Eachtreatmentis established on a plot 75m long by 15m wide. A subsurfacedrain is located in the center of each plot. Plots are isolatedwith plastic barriers. Drain flows, surface runoff and waterquality from conventionally drained andsubirrigated plots aremeasured year-round, in heated buildings. A state-of-the artdata acquisition and computer system monitors all functionsand collects data. Results of the experiment will be used to testcomputer simulation models and develop management practices for reducing nitrate pollution in runoff.

93-2126. EVALUATION OF DRAINMOD IN INDIAG.P. Gupta, RAJAD Research Project, Kota, Rajasthan, India; S.O. Prasher, Department of Agricultural Engineering,Macdonald Campus of McGill University, Ste-Anne-de-Bellevue, PQ; S.T. Chieng, Department of Bio-ResourceEngineering, University of B.C., Vancouver, BC; and I.N.Mathur, C.T.A.E., Rajasthan Agricultural University,Udaipur, Rajasthan, India.

The watertable management model DRAINMOD, wasevaluated for possible applications under semi-arid climaticconditions by comparing the predicted midspan watertableheights with the measured ones in four subsurface-drainedplotsin Kota,Indiaunderthe RAJAD(RAJasthanAgriculturalDrainage) Research project. In general, a good agreement wasfound between the measured data and the predicted values. Theaverage absolute deviations between the measured and predicted midspan table heights ranged from 140 to 240 mm forthe four test plots. The corresponding standard errors of estimate ranged from 150 to 300 mm. Based on our preliminaryinvestigations, it appears the DRAINMOD can be used todesign or evaluate subsurface drainage systems under thesemi-arid climatic conditions. However, further evaluationsare warranted before any concrete conclusions could be drawn.

93-2136. MEASURING AND SAMPLING SURFACERUNOFF AND SUBSURFACE DRAIN OUTFLOW VOLUME

M. Soultani, C.S. Tan, J.D. Gaynor, R. Neveu and C.F.Drury, Agriculture Canada, Harrow, ON.

An instrumentation system for automatically measuring andsampling surface runoff and subsurface drain outflow fromexperimental plots was developed. Surface runoff and subsurface drain outflow were channelled to a central collectionbuilding where volumes were measured and recorded by datalogger. The data stored in the datalogger were automaticallytransmitted to an IBM compatible computer at Harrow Research Station every 24 hours. Laboratory calibration and fieldverification of the system showed excellent agreement between actual and measured volume. The digital output from thewater measuring device was used to activate a water samplerat selected volumes.

93-2141. MODELING THE WATER BALANCE IN

COLD REGIONS

B.G. McConkey, Agriculture Canada, Swift Current, SK; D.J.Mulla, Washington State University, Pullman, WA; and D.K.McCool, USDA, Pullman, WA.

The Cold Region Agricultural Hydrology Model (CRAHM)

ABSTRACTS

was developed to integrate runoff and snow drifting with thesimulation of heat and mass transfer. One year is simulatedwithinoneminuteon a microcomputer usingsimple inputdataand parameters. The model provides good prediction ofrunoffand soil water content.

93-3030. IMAGE PROCESSING WITH "KHOROS" - APPLICATION TO GRAIN GRADINGJ.L. Hehn, P. Shatadal, D.S. Jayas and N.R. Bulley, Department of Agricultural Engineering, University of Manitoba,Winnipeg, MB.

This paper describes our experiences with an image processing package called Khoros from Khoral Research Inc. Itsvisual programming language (Cantata) and program development tool (Composer) are described. The application ofautomated grain grading research is used to demonstrate theusefulness of Khoros for conducting image processing research in Agricultural Engineering.

93-3031. CLASSIFICATION AND FEATURE MEASUREMENTS ON TOUCHING KERNELS OF WHEATAND BARLEY

P. Shatadal, D.S. Jayas, J.L. Hehn and N.R. Bulley, Department of Agricultural Engineering, University of Manitoba,Winnipeg, MB.

The images containing touchingkernels of wheat, barley,orboth were processed by a mathematical morphology basedkernel separation routine to remove the connecting pixels between the touching kernels. Morphological features wereextracted from the software-separated kernels. A Bayesianclassifier yieldeda correct classification for all the software-separated kernels.

93-3043. A DECISION SUPPORT SYSTEM FOR PESTICIDE USE MANAGEMENTD. Arjoon, R. Kok and S. Prasher, Department of Agricultural Engineering, Macdonald Campus, McGill University,Ste. Anne de Bellevue, PQ.

In this paper the authors describe a proposed decision support system which will be designed to aid managementpersonnelin their evaluationof groundwatercontamination bypesticides, and in making recommendations regarding alterations of, or additions to, on-farm management practices whichmay decrease the quantity of pesticide reaching groundwater.

93-3060. THREE-DIMENSIONAL COMPUTER AIDEDDESIGN OF FARM MACHINERY

J. Shen and R.L. Kushwaha, Agricultural and BioresourceEngineering Department, University of Saskatchewan, Saskatoon, SK.

For the shape and colour design of farm machinery, a package of AUTOLISP programs was developed which can be rununder AUTOCAD main environment. Based on AUTOCAD11.0 and AUTOCAD 12.0, the 3-D design functions of complex curved surface were enhanced in several main aspects. Asa demonstration, a tractor model was designed by using thepackage developed by the authors.

93-3063. A COMPUTER PROGRAM FOR CONTROL OF

CANNED FOOD STERILIZATION

A. Ryniecki and D.S. Jayas, Department of Agricultural En

gineering, University ofManitoba, Winnipeg, MB.Acomputer program, developed tocarry out experiments on

automatic determination of the step-response model parameters for computer control of canned food sterilization ispresented. The program was written using QuickBASIC forDOS environment (with Hercules, EGA, VGA, or SVGAgraphics adapter) and the Hewlett Packard 3852A data acquisition unit. This paper is the supplement to the paper ofRyniecki and Jayas published inthe Journal ofFood Engineering 19(l):75-94. All experiments described in thatpaper weredoneusing the computer program presented here.

93-3072. DYNAMIC RESPONSE SIMULATION OF ADIGITAL CONTROL SYSTEM FOR VARIABLE RATENITROGEN FERTILIZATIONY. Li, Mechanical Engineering Department; R.L Kushwahaand G.C. Zoerb, Agricultural and Bioresource EngineeringDepartment, University of Saskatchewan, Saskatoon, SK.

In this paper, the mathematical model and the digital controllers for the control system of variable rate nitrogenfertilization are introduced. The dynamic responses of thedigital controllers were simulated under certain conditions.The simulation results are analyzed in detail to determine thebest digital controller for the control process.

93-3076. IMPROVED DOUBLE EOR DRAWBAR PULLTRANSDUCER FOR 3-D FORCES MEASUREMENTS. Tessier, Departementde genie rural,UniversiteLaval,Quebec, PQ; and N. McLaughlin, CLBRR, Agriculture Canada,Ottawa, ON.

A drawbar force transducer dimensioned for tractor powerunder 100 kW is presented. This double extended octagonalring (DEOR) dynamometer is designed to simultaneouslymeasure drawbar draft, vertical and side loads without alteringthe tractor-implement hitch point configuration. Side loads arederived from the differential draft outputs of the two EORs.Two separate calibration runs demonstrate the good linearityof the EOR outputs. Individual EOR sensitivities are 1.7 and1.4mVtV"1 for draft and vertical drawbarfull loadsof 45 and13 kN, respectively. While output cross-sensitivity were expected this systematic source of error can be compensated byadding this effect to the predictive force equations.The doubleEOR dynamometer was used to measure drawbar force components of secondary tillage tools.

93-3081. EFFECT OF CHEMICAL PRE-TREATMENTSON MICROWAVE DRYING OF GRAPEST.N. Tulasidas, G.S.V. Raghavan and E.R. Norris, Department of Agricultural Engineering, Macdonald Campus ofMcGill University, Ste. Anne-de-Bellevue, PQ.

The microwave drying of grapes pre-treated with differentalkaline solutions was studied in a multimode cavity. Grapespre-treated with 2% ethyl-oleate in 0.5% sodium hydroxidesolution resulted into good quality raisins comparatively atlesser drying times. Pre-treatment with 3% ethyl oleate in 0.5%NaOH solution led to similar product without any major advantage over the former. Where as pre-treatment with 3% ethyloleate in 2.5% potassium carbonate resulted in slower dryingrate and was comparable to a pre-treatment with only 0.5%NaOH solution. Grapes pre-treated with pure NaOH solutionresulted in raisins of inferior quality in terms of colour and

CANADIAN AGRICULTURAL ENGINEERING Vol. 35, No. 3, JULY/AUGUST/SEPTEMBER 1993 233

appearance. Diffusion coefficients computed over the dryingperiod also suggest the effect ofthese chemical pre-treatments.Studies conducted on the effect ofwashing and time ofholdingafter the pre-treatment indicated that both of these factors haveno influence on drying time.

93-4002. STRESSES INDUCED BY THERMAL GRADIENTS IN CONCRETE LIQUID MANURE TANKS. Godbout and A. Picard, Civil Engineering Department,Laval University, Quebec, PQ; A. Marquis, Agricultural Engineering Department, Laval University, Quebec, PQ; andR.Jonas, Engineering Service, Agricultural Department, Quebec, PQ.

Temperature gradients across a concrete liquidmanure tankwall were monitored for a 16 month period in Quebec. Thetank was instrumented with 52 thermocouples installed oneach surface of a storage tank, 28 meter in diameter by 3.66meter deep. Inside and outside temperatures were measuredatthefourcardinalpoints. A temperature gradientof 30°Cacrossthe 200 mm wall thickness has been measured and should beconsidered for design. A similar gradient has been found between thermocouples 530 mm apart vertically on the samesurface. Thermal stresses resulting from the temperature gradients across the wall are presented. Impacts of thermalstresses on actual concrete liquid manure tank design guidelines are discussed.

93-4021. EFFECTIVENESS OF MANURE ADDITIVESN.K. Patni and P.Y. Jui, Research Branch, Agriculture Canada, Ottawa, ON.

Seven commercially available manure additives were testedfor their effectiveness in controlling the production of odour-producing chemicals, in reducing solids content, and inretaining nitrogen in stored swine manure slurry. None of theadditives showed a significant beneficial effect in controllingmanure slurry characteristics, although hydrogen cyanamide(H2NCN) was extremely effective in controlling hydrogensulfide gas production, and a 200 mm peat cover significantlyreduced the release of ammonia gas.

93-4022. APPLICATION OF A MANURE-N MANAGEMENT MODEL UNDER MANITOBA CONDITIONS

R. Sri Ranjan, T. Karthigesu and N.R. Bulley, Departmentof Agricultural Engineering, University of Manitoba, Winnipeg, MB.

A manure management model originally developed in British Columbia has been modified to be used under conditionsprevailing in Manitoba. The model uses soil type, weatherdata, the type of animals and the crop grown in Manitoba asinput parameters. The model incorporates the water and nutrient balance and takes into account the Nitrogen that is appliedboth as inorganic fertilizer and organic form. Based on cropgrowth characteristics it calculates the amount of nitrate that islost along with deep percolation. The model is capable ofcomparing different manure application strategies to minimizethe leaching of the nitrates to the ground water.

93-4024. EFFICIENT MANURE-N USE IN SILAGE

CORN PRODUCTION

B.J. Zebarth and J.W. Paul, Agriculture Canada AgassizResearch Station, Agassiz, BC; O. Schmidt, Dairy Producers'

234

Conservation Group, Abbotsford, BC; and R. McDougall,Hog Producers' Sustainable Farming Group, Abbotsford, BC

Preliminary results arepresented from a study on theinfluence ofthe rate and time ofliquid manure application onsilagecornyieldandNusein thelowerFraserValley, BritishColumbia. The results suggest that manure can be used to supply allorpartoftheNrequirement ofsilage corn with noloss inyield,or short term increase in thepotential fornitrate leaching.

93-4025. ON-FARM MEASUREMENT OF AVAILABLEMANURE-N

R.J. Fleming, J.E. Mclellan and S.H. Bradshaw, AgriculturalEngineering Section,CentraliaCollege,HuronPark,ON.

Two on-farm manure test procedures were evaluated todetermine their accuracy in predicting the concentration ofNH4-N in liquid manure. Onehundred andsixmanure samplesfrom swine, beef, dairy, and poultry farms were evaluated.Boththenitrogen meterandtheelectrical conductivity methodyielded reasonably accurate results. The estimates were farsuperior to those obtained using standard tables.

93-4026. NITRATE LEACHING AND DENITRIFICA-TION FOLLOWING FALL MANURE APPLICATIONJ.W. Paul and B.J. Zebarth, Agriculture Canada AgassizResearch Station, Agassiz, BC.

Three rates of dairy cattle slurry were applied to coarse andmedium textured soil in early October. The soil inorganic Nwas leached or denitrified from the soil during the fall andwinter. Denitrification rates were higher in manured plots onboth sides and highest for the coarse textured soil which had ashallow watertable.

93-4029. GRAIN WASTE COMPOSTING

M.T. Jacob, LH Resource Management Inc., Walton, ON.The Hensall Compost Facility (HCF) processes grain

screening wastes generated by three large grain cleaning/processing elevators. The HCF utilizes an in-vessel, open channelcomposting system which can handle 25 tonnes of feedstockmaterials daily. Finished compost is sold in bulk to farmers,nurseries and top soil companies.

93-4041. MEASURING AND MODELING GREEN

HOUSE MASS BALANCES

M. Trigui and L. Gauthier, Agricultural Engineering Department, Horticulture Research Center, Laval University,Quebec, PQ; and S. Barrington, Agricultural EngineeringDepartment, Macdonald Campus of McGill University, Ste.Anne de Bellevue, PQ.

Appropriate control of humidity in greenhouses is requiredto maintain crop transpiration and growth and to avoid diseasedevelopment or nutrient deficiencies. In the case of tomatocrops, humidity is usually in excess and must be extracted fromthe air. Since dehumidification under cold climates is essen

tially an energy consuming process, means to optimize thehumidity regimes are required. An approach involving transpiration models and management heuristics was developed andis presented. The proposed control strategy is based on target24 hour accumulated transpiration levels that can be set by thegrower and dynamically adjusted vapor pressure deficit set-points.

ABSTRACTS

93-4043. SIMULATION-BASED DETERMINATION OFGREENHOUSE TEMPERATURE SETPOINTSR. Lacroix andR. Kok, Department of Agricultural Engineering, Macdonald Campus of McGill University,Ste-Anne-de-Bellevue, PQ; and L. Gauthier, Department ofAgricultural Engineering, Laval University, Ste-Foy, PQ.

Aprototype simulation-based controller was developed andimplemented in a (simulated) greenhouse system, equippedwith a thermal screen. The role of the controller was to determine the setpoint path for the next 24 hours. This was doneoncea day by simulating the greenhouse behaviorin responseto anticipated meteorological conditions, with different set-point scenarios. Simulation-based control allowed thegreenhouse system to adapt itself to the anticipated disturbances and to behave more optimally than with a traditionalcontroller. High night temperatures were maintained whenoutside temperature and solar radiation intensity were anticipated to be high. This control approach reduced the heatingload by amounts varying from 5 to 14%.

93-5009. GREENHOUSE EFFECT: RESPONSIBILITYOF AGRICULTURAL ENGINEERSA. St.-Yves, Sainte-Foy Research Station, Agriculture Canada, Sainte-Foy, PQ.

Studies show that agriculture contributes mainly in emission of greenhouse gases from diffuse sources and from largeterritories. Greenhouse effect is an important public concern.Many countries agreed to work on this issue in Brasilia, lastyear. By virtue of their ability, agricultural engineers have amajor role to play and must contribute in their field of practice,in setting minimisation strategies and finding suitable solutions to the problem.

93-6011. ARGON EFFECT ON GAS ANALYSIS FORCONTROLLED ATMOSPHERE STORAGE

B. Goyette and C. Vigneault, Agriculture Canada ResearchStation, Saint-Jean-sur-Richelieu, PQ; and G.S.V. Raghavan,Agricultural Engineering Department, Macdonald Campus ofMcGill University, Ste. Anne de Bellevue, PQ.

The conventional gas chromatographic method used tomeasure the gas composition of controlled atmosphere storageor modified atmosphere packing of fruit or vegetable does notconsider the argon. The conventional method used does notseparate the argon from the oxygen resulting in an overestimate of the oxygen generally ranging between 5 to 80% of thereading. This error mainly depends on the CA technique usedand the airtightness of the storage system. A new method ofgas chromatography was developed and tested to evaluate thegas concentration contained in a CA room. The results of thetwo methods are compared.

93-6019. DISTRIBUTION OF INTRODUCED CARBON

DIOXIDE IN FARM GRANARIES: AN EXPERIMEN

TAL INVESTIGATION

K. Alagusundaram, D.S. Jayas and W.E. Muir, Departmentof Agricultural Engineering, University of Manitoba, Winnipeg, MB; and N.D.G. White and R.N. Sinha, AgricultureCanada Research Station, Winnipeg, MB.

Experiments were conducted in three 5.56-m-diameterbolted metal bins, either empty or filled with wheat, to determine the distribution and maintenance of carbon dioxide

(CO2) gas. Bins 1, and 2 were filled with wheat to adepth of2.50 m and 2.10 m respectively, and Bin 3 was empty in theexperiments. Dry ice was used as a source of CO2 gas. Theeffects of the point application of dry ice, the amount andfrequency ofapplication ofdry ice, the grain surface left openor covered with polyvinylidene chloride sheets (PVC) andsealing various portions ofthe bin inprogression on the distribution and retention of CO2 were studied.

93-6021. EFFECTS OF OIL TREATMENT AND STORAGE TEMPERATURE ON MILLING QUALITY OFHRS WHEATW. Lang, J. Irudayaraj and S. Sokhansanj, Department ofAgricultural and Bioresource Engineering; and F.W.Soulski,Department of Crop Science andPlantEcology, University ofSaskatchewan, Saskatoon, SK.

No. 1 HRS wheat (Triticum aestivum) Kenyon variety weretreated with five application levels of canola oil: 0 (control),200, 400, 800, 1600 and 2000 ppm. The treated samples werestored at 22 and -25°C. Effects of oil treatments and storagetemperature on qualitiesassessedafter 18monthsof storage insealed containers were largely prevented by the cold temperature. Increasing rates of oil application up to 2000 ppmresulted in greater losses in flour yield and darkening of wheatkernel but whitening of the bran. Oil treatment at any levelreduced gluten strength of the flour proteins but these effectswere largely controlled by the cold storage temperature. Except for flour yield, storage of oil-treated wheat in WesternCanada for prolonged periods would be adversely affected,butstorage at room temperature reduced wheat, flour and glutenquality, even at the recommended 200 ppm of oil applicationfor dust control.

93-6030. COMBINED FIELDS DEWATERING OF SEAWEED (NEREOCYSTIS LUETKEANA)D.G. Lightfoot, C.P.I. Equipment Ltd, Parksville, BC; andG.S.V. Raghavan, Department of Agricultural Engineering,Macdonald Campus, McGill University, Ste. Anne deBellevue, PQ.

Increasing pressures on our agricultural systems necessitatethe investigation of alternative food and feed sources. Theocean coasts of the world provide one potential alternative, asthey provide a habitat for millions of tonnes of brown marinealgae, or kelp. In this study, a combined fields (mechanicalpressure and electro-osmosis) dewatering technique was investigated for dewatering kelp. Electro-osmosis has beenshown to significantly improve conventional press dewateringof kelp. Dewatering kelp, was found to significantly reduce itsash contents and available carbohydrates, and increase its protein, fat, and uronic acid contents. Furthermore, energy costsfor producing dried kelp meal were found to be significantlylower if dewatering precedes thermal drying.

93-6051. COMPRESSION CHARACTERISTICS OF AL

FALFA CUBES

R.T. Patil, S. Sokhansanj and M.H. Khoshtaghaza, Department of Agricultural and Bioresource Engineering, Universityof Saskatchewan, Saskatoon, SK.

The mechanical properties of alfalfa cubes influence theirchewability and durability. The effect of crosshead speed,probe size and orientation of cubes for testing mechanical

CANADIAN AGRICULTURAL ENGINEERING Vol. 35, No. 3, JULY/AUGUST/SEPTEMBER 1993 235

properties indicated that only probe diameter is an importantfactor. Three modes of compression tests such as penetrationwith cylindrical probe, bending andcompression under 750Nwere selected to simulate various handling practices. For firsttwo methods the load deformation relationship was expressedas modulus of deformability and modulus of rupture, respectively. For third method of compression under 750 N, thepercent deflection was measured. The method of penetrationwith the cylindrical probe at 20 mm/min was found suitablemethod to specify relative hardness of alfalfa cubes.

93-6052. HEAT TRANSFER COEFFICIENTS ASSOCIATED WITH ROTATIONAL PROCESSING OF FOODMODELS

H.S. Ramaswamy, S.S. Sablani and C. Abbatemarco, Department of Food Science, McGill University, Macdonald

236

Campus, Ste. Anne de Bellevue,PQ.Heating transfer characteristics ofcanned models food (ge

latinized starch, water and oil) processed in rotationalautoclaves were evaluated in relation to various factors (retorttemperature, 110-130°C; rotation speed 0-20 rpm, and productviscosity, 0.001 to 0.6Pa*s). Time-temperature data gatheredduring processing were used to gather the heating rate index(fh) which was related to overall heat transfer coefficient (U)using the lumped capacity approach. The fluid-to-particle heattransfer coefficient (hfp) values were obtained from the solution to transient heat conduction equations involving finitesurface convection. The U values varied from 180 to 550W^m'Vc"1 for starch, 120 to 160 W^m'Vc1 for oil and510 to 930 W»m" ^C"1 for water. hfp values ranged from20-120 W»m" •°C" under the various operating conditions.

ABSTRACTS

NOTES TO CONTRIBUTORS

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