Designing and testing Danish Research Centre for Organic Farming crop rotations for organic farming Proceedings from an International workshop Jørgen E. Olesen, Ragnar Eltun, Mike J. Gooding, Erik Steen Jensen & Ulrich Köpke (Eds.) DARCOF Danish research in organic Farming The remit of Danish Research Centre for Organic Farming (DARCOF) is to initiate and co-ordinate Danish research in organic farming. DARCOF is a "centre without walls" meaning that scientists remain in their own environments but work across institutions. The activities at DARCOF comprise presently 20 institutes, around 140 scientists and 40 – 50 ongoing projects. Danish Research Centre for Organic Farming Foulum • P.O. Box 50 • DK-8830 Tjele Tel. +45 89 99 16 75 • Fax +45 89 99 16 73 E-mail: [email protected] Homepage: www.foejo.dk Designing and testing crop rotations for organic farming Proceedings from an international workshop DARCOF Report no. 1 Printed from www.foejo.dk Jørgen E. Olesen, Ragnar Eltun, Mike J. Gooding, Erik Steen Jensen & Ulrich Köpke (Eds.) Danish Research Centre for Organic Farming 1999 DARCOF Report No. 1/1999 Designing and testing crop rotations for organic farming Proceedings from an international workshop Editors Jørgen E. Olesen, Danish Institute of Agricultural Sciences Ragnar Eltun, The Norwegian Crop Research Institute Mike J. Gooding, The University of Reading, UK Erik Steen Jensen, The Royal Veterinary and Agricultural University, Denmark Ulrich Köpke, Institute of Organic Agriculture, University of Bonn, Germany Layout Cover: Enggaardens Tegnestue Content: Grethe Hansen, DARCOF Photos: E. Keller Nielsen Print: Repro & Tryk, Skive, Denmark Paper: 90 g. Cyklus print Paginated pages: 350 First published: December 1999 Publisher: Danish Research Centre for Organic Agriculture, DARCOF ISSN: 1399-915X Price: 100 DKK incl. consignment To be bought at Danish Research Centre for Organic Agriculture, DARCOF Research Centre Foulum P.O. Box 50 DK-8830 Tjele Tel. +45 89 99 16 75, fax +45 89 99 12 00 E-mail: [email protected] Homepage: www.foejo.dk Preface The interest in organic farming is increasing in many industrialised countries, both as a consequence of consumer demands and because organic farming is seen as one of the ways towards sustainable agriculture. Organic farming aims at establishing stable and harmonic farming systems, which integrate livestock and crop production. No industrial fertilisers, pesticides or growth regulators are used. The nutrient management is based on the use of animal manure, green manure, crop residues and on nitrogen fixation by legumes. Weeds, pests and diseases are controlled through the use of versatile crop rotations, mechanical weed control and a proper choice of varieties. The multifunctional crop rotation is thus a key component in organic farming. The design of these crop rotations is a major challenge for farmers as well as for agronomic research. The different aspects of crop rotations have been investigated by a range of methods, including long- term trials, factorial experiments and on-farm monitoring. However, there has been little effort into bringing these results and experiences together into a common understanding of the functioning of crop rotations and the methods by which they are best explored. In this context, there is a great need for international co-operation. A workshop on crop rotations for organic farming was therefore organised in Denmark in June 1999. The workshop aimed at bringing together researchers working with different aspects of crop rotations for organic farming. This proceeding presents the lectures given at the workshop, as well as summaries of the discussions. The desire is to contribute to the development of research in crop rotations in organic farming, and to promote the international co-operation in the area. This would not have been possible without the efforts of the individual authors, the editorial group and the organisers of the workshop. Our sincere thanks are therefore extended to all those involved in the workshop and in the creation of this book. Erik Steen Kristensen Head of Danish Research Centre for Organic Farming Foulum, December 1999 3 4 Contents Overview ................................................................................................................................................ 9 Perspectives for research on cropping systems............................................................................ 11 J.E. Olesen Crop rotations in organic farming: theory and practice.............................................................. 21 F.W.T. Wijnands Using plant species composition to restore soil quality and ecosystem function ................... 37 L.E. Drinkwater Long-term crop rotation experiments.............................................................................................. 47 Design of the Danish crop rotation experiment.......................................................................... 49 J.E. Olesen, I.A. Rasmussen, M. Askegaard and K. Kristensen Agronomic considerations and dilemmas in the Danish crop rotation experiment............... 63 M. Askegaard, J.E. Olesen and I.A. Rasmussen Ten years experience of all-arable rotations ................................................................................. 71 L. Philipps, J.P. Welsh and M.S. Wolfe Yield results during the first eight years crop rotation of the Apelsvoll cropping system experiment ......................................................................................................................................... 79 R. Eltun and O. Nordheim Designing crop rotations for organic farming: importance of the ley/arable balance........... 91 C.A. Watson, D. Younie and G. Armstrong Crop rotation research in Central Oltenia..................................................................................... 99 G. Paunescu and F. Ionescu Long-term crop rotations experiments in Latvia......................................................................... 107 L. Zarina and V. Mikelsons Whole crop rotation and farm studies.............................................................................................. 113 Testing a stockless arable organic rotation on a fertile soil........................................................ 115 W.F. Cormack Nutrient balances and yields during conversion to organic farming in two crop rotation systems ............................................................................................................................................... 125 Å. Asdal and A.K. Bakken 5 An organic vegetable crop rotation self-sufficient in nitrogen .................................................. 133 K. Thorup-Kristensen Crop yields from three organic farm systems at Rugballegaard ................................................ 141 F. Oudshoorn and I.S. Kristensen Partner farms: a participatory approach to collaboration between specialised organic farms 149 W.J. Nauta, G.J. v/d Burgt and T. Baars Crop rotations on organic farms in Northern Germany and development of the wide row system ................................................................................................................................................ 159 R. Holle and U. Untiedt Nitrogen cycling and crop production ............................................................................................ 163 Influence of 2-, 3-, 4- and 5-year stands of alfalfa on winter wheat yield ................................ 165 E. Campiglia, F. Caporali, B. Barberi and R. Mancinelli Measurement of nitrogen partitioning within different organic systems incorporating strip intercropping, sheep and crop rotation......................................................................................... 173 S.A. Jones and P.M. Harris Dinitrogen fixation and residue nitrogen of different managed legumes and nitrogen uptake of subsequent winter wheat................................................................................................ 181 R. Loges, A. Kaske and F. Taube Importance of varying management and environmental conditions in a long-term crop rotation trial. Effects on plant development, crop yield and nitrogen dynamics.................... 191 H. Schmidt and P.v. Fragstein External N sources in an organic stockless crop rotation - useful or useless additives? ....... 203 P.v. Fragstein and H. Schmidt Strategies to avoid nitrate leaching after potato crops by applying different cultivation methods to the following cereals.................................................................................................... 213 H.J. Reents and K. Möller The proportion of green fallow in stockless farming systems: Grain yield, nitrogen leaching and soil organic matter ..................................................................................................... 223 H. Høgh-Jensen Simulation of plant production and N fluxes in organic farming systems with the soil-plant atmosphere model DAISY.............................................................................................................. 235 L.S. Jensen, T. Müller, J. Eriksen, K. Thorup-Kristensen and J. Magid 6 Nutrient availability ............................................................................................................................. 249 The sulphur balance of organic crop rotations in Denmark...................................................... 251 J. Eriksen, M. Askegaard, J.E. Olesen and K. Thorup-Kristensen Nutrient management and plant