Quality of Life and Management of Living Resources Dupraz C., Burgess P., Gavaland A., Graves A., Herzog F., Incoll L.D., Jackson N., Keesman K., Lawson G., Lecomte I., Liagre F., Mantzanas K., Mayus M., Moreno G., Palma J., Papanastasis V., Paris P., Pilbeam D.J., Reisner Y., Van Noordwijk M., Vincent G., Werf Van der W. The SAFE European Project SILVOARABLE AGROFORESTRY FOR EUROPE This final report is dedicated to Jacques Maffert. Jacques was one of the most enthusiastic farmer and partner. This tree (top, left) was his tree at the Pys farm near Lezat/Leze in Haute- Garonne (France). He planted some superb new agroforestry plots on his farm in 2000 (top, right). He died in a car crash in July 2001. He would have been a key SAFE partner. Those who met Jacques will never forget him. The SAFE European Project SILVOARABLE AGROFORESTRY FOR EUROPE Page 3 List of authors Dupraz Christian, Lecomte Isabelle. INRA , UMR Systèmes de Culture Méditerranéens et Tropicaux, 2, Place Viala, 34060 Montpellier, France. Content CONTENT 5 SUMMARY 9 INTRODUCTION 15 MATERIAL AND METHODS 17 WP1: The SAFE modelling platform 18 WP2: European silvoarable knowledge 18 WP3: European silvoarable experimental network 18 WP4: Modelling above-ground tree-crop interactions 19 WP5: Modelling below-ground tree-crop interactions 19 WP6: Production of an integrated model of tree-crop interactions 19 WP7: Economic modelling at the plot scale 20 WP8: Up-scaling to the farm and region scale 20 WP9: Developing European guidelines for policy implementation 21 RESULTS 22 WP1: A platform for modelling silvoarable systems 23 WP2: Extant silvoarable systems in Europe 25 The agroforestry publication database 25 The extant silvoarable systems in Europe database 25 Survey of farmers' reaction to modern silvoarable systems 27 WP3: European silvoarable experimental network 31 Providing field experimenters with a forum for exchanging know-how and expertise. 32 Managing field experiments in a sound and concerted way 32 Providing data from field experiments in a standardised format for model parameterisation and testing. 34 Collecting data from the Experimental Sites 37 Reporting the results of silvoarable experiments 45 WP4: Modelling above-ground tree-crop interactions 59 Characterisation of tree and crop competition for light 59 The Hi-sAFe light competition module 72 Interactions between trees and crops through the modification of the microclimate 75 The tree growth module of the Hi-sAFe model 75 Summary - Page 5 WP5: Modelling below-ground tree-crop interactions 77 Field evidence calling for a new approach to below-ground competition modelling in silvoarable systems 77 An innovative dynamic model of tree fine roots 80 An innovative water and nitrogen competition model between trees and crops 83 WP6: Production of integrated models of tree-crop interactions 85 The Hi-sAFe model 85 The Yield-sAFe model 92 WP7: Economic modelling at the plot scale 108 Review of existing financial models 108 Selection and development of a plot- and farm-scale economic model 109 Use of templates to identify and quantify inputs, outputs, costs and revenues for the silvoarable system network systems, and existing arable and forestry enterprises for different parts of Europe 114 Use of the model to identify the most profitable agroforestry systems for the network sites and their sensitivity to changes in prices and grants 114 Use of the Yield-sAFe model to determine the optimum silvoarable system for high potential locations 130 Use of an LER-based-generator model to determine the optimum silvoarable system for high potential locations in France 150 WP8: Up-scaling to the farm and region scale 154 Assessing the environmental effects of agroforestry at the landscape scale 154 Defining target regions for silvoarable agroforestry for Europe 162 WP9: Developing European guidelines for policy implementation 171 Documenting the problems of farmers establishing new silvoarable plots in 5 European countries. 171 Comparing eligibility of silvoarable systems for Government financial 172 Proposing changes in forestry and agroforestry policy based on scenario testing using models. 174 Co-ordinating the establishment of silvoarable plots as a ‘social experiment’ by user participants in 3 countries. 176 DISCUSSION 180 WP1: A platform for modelling silvoarable systems 181 WP2: Extant silvoarable systems in Europe 182 The extant silvoarable systems in Europe database 182 Survey of farmers' reaction to modern silvoarable systems 182 WP3: European silvoarable experimental network 188 WP4: Modelling above-ground tree-crop interactions 189 About the consistency of the above-ground modules in Hi-sAFe 189 The failure to provide a micro-climate module 190 Future Improvements and potential issues 191 WP5: Modelling below-ground tree-crop interactions 193 About the characterization of the root systems of trees in silvoarable fields 193 About novel approaches to modelling the dynamics of tree root systems in heterogeneous soils 193 Summary - Page 6 About container experiments to validate the root voxel automata 194 About the novel approach to water and nitrogen competition introduced in Hi-sAFe 195 WP6: Integration of biophysical models of tree-crop systems 197 About the detailed Hi-sAFe model. 197 About the simple Yield-sAFe model. 197 WP7: Economic modelling at the plot scale 199 About the sensitivity analysis of the silvoarable systems 199 About the use of an LER-based-generator model to determine the optimum silvoarable system for high potential locations in France 202 WP8: Up-scaling to the farm and region scale 210 About target regions for silvoarable systems 210 Critical remarks 210 About the up-scaling of the profitability assessment at the Land Test Sites across Europe 21 WP9: Developing European guidelines for policy implementation 214 SAFE Proposal 1. The following definition of agroforestry is suggested by the SAFE consortium and could be included in the new RDR regulation. 214 SAFE Proposal 2. The total area of the agroforestry parcel is eligible for the Single Payment Scheme. 215 SAFE Proposal 3. Planting and maintenance costs of new agroforestry plantings should be met within the new RDR, and improvement of existing agroforestry systems be supported by agri-environment payments. 216 SAFE Proposal 4. Ensure that the EU Action Plan for Sustainable Forest Management emphasises the need to very greatly increase the presence of scattered trees in farmed landscapes (agroforestry) 216 CONCLUSIONS 218 WP1 recommendations 220 WP2 recommendations 220 WP3 recommendations 220 WP4 recommendations 221 WP5 recommendations 221 WP6 recommendations 221 WP7 recommendations 221 Use and improvement of the biophysical and economic model 221 Plot-scale economic analysis 221 General recommendation 222 EXPLOITATION AND DISSEMINATION OF RESULTS 224 POLICY RELATED BENEFITS 226 Contribution to EU policies 226 European dimension of the problem 226 Contributing to policy design or implementation 227 Summary - Page 7 Contribution to EU social objectives 229 Improving the quality of life in the Community: 229 Creating jobs in the Community 230 Supporting sustainable development, preserving and/or enhancing the environment 230 LITERATURE CITED 231 LIST OF THE SAFE PROJECT PUBLICATIONS 242 Papers published or accepted for publication 243 Papers submitted 245 Papers in preparation 246 Extension papers 247 In French 247 In English 249 In German 249 In Spanish 249 In Dutch 249 In Italian 249 In Portuguese 250 Internal reports 251 Posters 252 Communications to congresses 253 Summary - Page 8 Summary The SAFE research project was sponsored by the European Union, and was coordinated by INRA (France). More than 70 scientists from eight European countries participated in the project from August 2001 to January 2005. The SAFE project explored how trees could be maintained or re-introduced in agricultural systems of Europe. In agroforestry systems, trees and crops (or pastures) are mixed purposefully. The most prominent results are detailed below. 1. Many traditional European agroforestry systems disappeared th during the 20 century. Intensification, mechanisation and land consolidation were the most important incentives for tree removal from cultivated areas. Isolated trees, trees in hedges, and low-density tree stands (such as traditional high-stem low density orchards) were massively removed. 2. The Common Agriculture Policy (CAP) was another reason for the removal of trees from agricultural systems in Europe during the last 30 years. Trees are not considered part of the cropping systems, and CAP payments for crops or pastures are often reduced for parcels with scattered trees (including boundary trees). This negative impact was not an objective of the CAP, but was the consequence of regulations that do not take into account the positive impact of rural trees. In the new member states, CAP regulations may induce the destruction of millions of trees in the coming decade. 3. The loss of many traditional agroforestry systems in Europe has had unfortunate consequences: loss of know-how by farmers, simplification and standardization of landscapes, increased environmental problems such as soil erosion and water pollution, significant carbon release, reduction of biodiversity, loss of habitat for natural enemies of crop pests, and the loss of a source of alternative income for farmers. Summary - Page 9 4. For the past four years, accurate monitoring of trees and crops in various silvoarable systems has been performed in experimental plots in France, England, Spain and Italy. The impact of tree density, tree size and tree pruning schemes on crops productivity was analysed, quantified and modelled. 5. The SAFE project has demonstrated that modern agroforestry systems are compatible with present-day agricultural techniques. Specific tree management schemes are necessary (such as tree alignment and stem formative pruning). In modern agroforestry systems, low final tree densities (30-100 trees/ha) allow crop production to be maintained until tree harvest. The SAFE project similarly has demonstrated that the average productivity of silvoarable systems is higher than the combined productivity of separate tree and crop systems. Productivity increases of up to 30% in biomass, and 60% in final products have been observed. 6. Biophysical models have been constructed to simulate the dynamics of tree-crop systems in various soil and climatic conditions. These models allow predictions of competition for light, water and nitrogen between trees and crops. They also predict how many years the crops will be profitable, and how fast the trees will grow. Finally model outcomes exemplify some very favourable environmental impacts of tree-crop systems, such as a reduction in nitrogen leaching or an increase in carbon sequestration. Management practices for silvoarable systems can thus be evaluated through ‘virtual experiments’ on computers using these models. 7. A key result of the SAFE project is that tree-crop systems are able to capture more resources from the environment than pure crop or pure tree systems: competition induces adaptation, and adaptation results in facilitation, a process that explains why mixed plots are significantly more productive than pure plots. 8. Using the SAFE models, optimum management schemes can be derived for tree stand densities, tree spacing, tree row orientation, tree species choice, intercrop rotation choice, and specific tree and crop management techniques, such as tree root pruning. 9. Economic calculations show that agroforestry plots are often as profitable as agricultural plots in no-grant scenarios, and that they are often more profitable when including high value timber trees (such as walnut or Sorbus trees). Annual crops maintain the annual income for the farmer, while managed low density tree stands provide capital for the future. 10. However current policies totally prevent European farmers from adopting silvoarable agroforestry: in most cases, farmers will loose the crop payments and are not eligible for any subsidy to plant the trees. This is why at the moment agroforestry is artificially unattractive for European farmers (with the exception of France who recently has adapted its regulations). 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