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Prediction of the Immediate Effect of Traffic on Field Soil Qualities

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Prediction of the Immediate Effect of Traffic on Field Soil Qualities PREDICTION OF THE IMMEDIATE EFFECT OF TRAFFIC ON FIELD SOIL QUALITIES Ontvangen 28 Ml f994 UB-CARDEX CENTRALE LANDBOUWCATALOGUS 0000 0574 2693 Promotor: ir. H. Kuipers emeritus hoogleraar grondbewerking Co-promotor: dr.ir. A.J. Kooien universitair hoofddocent gronddynamica |JMog>2o', iBd3> P. Lerink PREDICTION OF THE IMMEDIATE EFFECT OF TRAFFIC ON FIELD SOIL QUALITIES Proefschrift ter verkrijging van de graad van doctor in de landbouw- en milieuwetenschappen op gezag van de rector magnificus, dr. CM. Karssen, in het openbaar te verdedigen op woensdag 29 juni 1994 des namiddags te half twee in de Aula van de Landbouwuniversiteit te Wageningen. Ufevi^S- CjCj ICJ( CIP-DATA KONINKLIJKE BIBLIOTHEEK, DEN HAAG Lerink, P. Prediction of the immediate effect of traffic on field soil qualities / P. Lerink. - [S.I. : s.n.]. -III . Thesis Wageningen. - With réf. - With summary in Dutch. ISBN 90-5485-267-4 Subject headings: soil compaction / field traffic. ölbUOIHEK« LAfNDBOUWÜNIYESS; WAGENINGEH Printed by Grafisch Service Centrum, Van Gils B.V. Acknowledgements finance, logistics Wageningen Agricultural University discussions J.B. Dawidowski, A.J. Kooien, H. Kuipers assistance L.C. Blanken, A. Boers, J.J. Klooster, B. Kroesbergen F.J.M, van Oorschot, B.W. Peelen f-> UOSZJD^ lôûg> STELLINGEN 1. Als gevolg van het toepassen van brede lagedruk banden neemt de berijdingsintensiteit toe. Het nadelige effect van berijden op de fysieke bodemgesteldheid, gemeten in het spoor waar dit effect maximaal is, neemt daarbij af. Dit proefschrift. 2. Een nauwkeurig en handzaam instrument voor het bepalen van de vochttoestand van de bouwvoor is een onmisbaar hulpmiddel bij het kiezen van het juiste bewerkings-tijdstip en/of het voorspellen van de effecten van berijding. Dit proefschrift. 3. Voor het bepalen van hetoptimal e bewerkingsfijdstip is het te verwachten effect van berijding op de fysieke bodemgesteldheid het belangrijkste criterium. Dit proefschrift. 4. Bij het onderzoek van het verdichtingsproces van landbouwgrond door berijding bevindt de kennis van de bodemvervorming zich nog in een begin stadium. Dit proefschrift. 5. Bijverdichtin g van gestructureerde gronden als gevolg van berijding is het verband tussen het poriënvolume en de fysieke bodemgesteldheid niet eenduidig. Dit proefschrift. 6. Dit onderzoek heeft (opnieuw) aangetoond dat onze banden met Moeder Aarde niet van dien aard zijn dat wij ongelimiteerd druk op haar kunnen uitoefenen. H.J. van Dijk. 7. De tijd- en plaatsafhankelijke variabiliteit van de fysieke gesteldheid van de bouwvoor op perceelsniveau wordt vooral bepaald doord eeffecte n van berijding. 8. Een auto werkt op zijn bestuurder als een morele kooi van Faraday. 9. Het denkbeeldige weerstandspunt van een ploeg met lange risters ligt dichter bij het geploegde dan in het algemeen wordt aangenomen. 10. Het feit dat jagers en vissers niet op gelijke voet bejegend worden komt vooral door het verschil in sociale status tussen beide groepen. 11. Begripsvernauwing omvat al datgene dat te maken heeft met geestverarming na kennisverrijking. Aan begripsvemauwing ontsnappen alleen onderzoekers met hobby's. W. Karsijns. 12. De natuurlijke vruchtbaarheid, de geringe onkruiddruk en de goede vochthuishouding van de Nederlandse zavel- en kleigronden vormen een belangrijke basis voor duurzame landbouwsystemen. Stellingen behorende bij het proefschrift "Prediction of the immediate effect of traffic on field soil qualities" van P. Lerink. Wageningen, 29 juni 1994. voor Margriet Abstract Lerink, P. (1994) Prediction of the immediate effect of traffic on field soil qualities. Ph.D. thesis, Department of Soil Tillage, Wageningen Agricultural University, The Netherlands, pp. 127, 22 figs, 16 tables, 129 refs, Dutch summary. Field traffic by heavy machinery and transport vehicles is an integral part of modern arable crop production systems. The greater part of the field area is trafficked once or several times per year during the successive field operations. The traffic induced effect on the soil physical condition isofte n considered detrimental andmus t beminimize d within the margins of practical and economical feasibility. The object ofthi s study is to establish a strategy for prediction of the effects of traffic to be used on a farm scale. The prediction method is based on a drastic limitation of the domain of prediction: a single field, two traffic systems, andtw o types offiel d operations. The effect ofcompactio n byfiel d traffic is expressed by so called soil qualities, i.e. soil physical properties which contain relevant information for the soil user. The soil condition atth e time a certain field operation is performed is described by a single soil characteristic only: the gravimetric water content. Field traffic is characterized by the type of field operation and the type of traffic system. These characteristics are further described in terms of the tyre inflation pressure, the wheelload and the number of wheelings. The prediction functions, relating soil and traffic characteristics to the expected effect on soil qualities are established by means of a comparative method, and based on laboratory measurements onfiel d compacted soil. The prediction functions are presented by means of extended M-P-V diagrams. In the discussion of the experimental results, the significance of supplementary laboratory compaction methods are mentioned. Moreover, the extension ofth e prediction functions to situations beyond the domain considered in this study is briefly explored. Additional keywords: soil compaction, field soil characteristics, traffic characteristics, prediction, physical soil properties. Copyright P. Lerink, 1994. No part of this book (with the exception of the abstract on this page, and the appendices) may be reproduced or published in any form and by any means without permission from the author or the Department of Soil Tillage of the Wageningen Agricultural University. CONTENTS INTRODUCTION 11 SYNOPSIS 13 INTRODUCTION TO THE SYSTEMATICS OF FIELD TRAFFIC AND THE FIELD SOIL CONDITION 14 SYSTEMATICS OF FIELD TRAFFIC 16 4.1 Preliminary remarks 16 4.2 The occurrence of field traffic 17 4.3 Spatial aspects of field traffic 19 4.4 Time aspects of field traffic 21 4.5 Factors determining the compaction capability of field traffic 25 4.5.1 Preliminary remarks 25 4.5.2 Traffic characteristics 27 4.5.3 Traffic characteristics of a given set of farm machinery 32 4.6 Closing remarks on systematics of field traffic 35 SYSTEMATICS OF THE FIELD SOIL CONDITION 37 5.1 Preliminary remarks 37 5.2 Strength related soil properties 38 5.5.1 Macro-factors 38 5.5.2 Micro-factors 39 5.3 Mechanical processes 40 5.3.1 Compaction processes 41 5.3.2 Stress factors determining the compactibility in strength hardening processes 42 5.3.3 Soil factors determining the compactibility in strength hardening processes 44 5.3.4 Stress factors determining the flowability 48 5.3.5 Soil characteristics determining the flowability 48 5.3.6 The effect of compaction on soil physical properties 49 5.3.7 Closing remarks on compaction 52 5.3.8 Loosening processes 53 5.4 Natural soil processes 54 5.4.1 Preliminary remarks 54 5.4.2 The effect of some important natural soil processes on the soil strength 54 5.5 Soil characteristics of a given field 61 THE METHOD OF PREDICTION 65 6.1 Preliminary remarks 65 6.2 Methods of prediction 65 6.3 Closing remarks on existing prediction methods 68 6.4 Prediction based on empirical methods 69 6.4.1 The prediction function 69 6.4.2 Where to predict from (X;) 71 6.4.3 What to predict (Y) 73 PREDICTION FUNCTIONS BASED ON OBSERVATIONS ON TRAFFIC COMPACTED SOIL 75 7.1 Preliminary remarks 75 7.2 Experimental lay-out of the HGP/LGP research project 75 7.3 Experimental methods 79 7.3.1 Choice of field operations and sampling locations 79 7.3.2 Field sampling procedure 81 7.3.3 Laboratory preparation and measurements methods 83 7.3.4 Calculation and data processing 85 7.4 Results 88 7.4.1 Presentation 88 7.4.2 Estimation of the prediction function (F) 93 7.5 Analysis 93 7.5.1 The effect of the water content at compaction 94 7.5.2 The effect of the type of traffic system 98 7.5.3 The effect of the type of field operation 98 7.6 Analysis of factors causing disturbance 99 7.6.1 The reliability of the prediction curves 99 7.6.2 The effectiveness of the prediction curves 103 7.6.3 Variance of the compactibility 106 8 LABORATORY SIMULATION OF THE EFFECTS OF COMPACTION BY FIELD TRAFFIC 109 9 THE EXTENSIBILITY OF THE PREDICTION METHOD 111 10 CONCLUSION 112 11 SAMENVATTING (Dutch) 114 REFERENCES 118 CURRICULUM VITAE 127 APPENDICES I. Summation of shear deformation in stream tubes in soil under a moving tyre. by: F.G.J Tijink, P. Lerink and A.J. Kooien 131 II. Controlled distortion of soil samples with reference to soil physical effects. by: J.B. Dawidowski, P. Lerink and A.J. Kooien 154 III. Laboratory simulation of the effects of traffic during seedbed preparation on soil physical properties using a quick uni-axial compression test. by: J.B. Dawidowski and P. Lerink 170 IV. Prediction of the immediate effects of traffic on field soil qualities. by: P. Lerink 185 V. The kneading distortion apparatus. by: P. Lerink 199 VI. Prediction of aspects of soil-wheel systems. by: A.J. Kooien, P. Lerink, D.A.G. Kurstjens, J.J.H. van den Akker and W.B.M. Arts 206 INTRODUCTION The soil physical condition is only one of many factors determining the quality of agricultural field soils for crop production purposes. The physical condition of a field soil is not a constant, but changes continuously owing to man-induced and natural processes. In modern countries, the field activities by man are fully mechanized. In the Netherlands, scientific research on various aspects of soil- machine systems was started in 1959 by Emeritus Professor H.
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