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The development of integrated crop-livestock systems (ICLS) is a major challenge for the ecological modernisation of agriculture but appears difficult to implement at a large scale. A participatory method for ICLS design has been developed and implemented in 15 case studies across Europe, representing a range of production systems, challenges, constraints and resources for innovation. Local stakeholders, primarily farmers, but also cooperatives, environmental-association representatives and natural-resource managers, were involved in the identification of challenges and existing initiatives of crop-livestock integration; in the design of new options at field, farm and territory levels; and then in qualitative multicriteria assessment of these options. A conceptual framework based on a conceptual model (crops, grasslands, animals) was developed to act as a boundary object in the design step and invite innovative thinking in 'metabolic' and 'ecosystemic' approaches. A diversity of crops and grasslands interacting with animals appeared central for designing sustainable farming systems at the territory level, providing and benefitting from ecosystem services. Within this diversity, we define three types of integrated systems according to their degrees of spatial and temporal coordination: complementarity, local synergy, territorial synergy. Moreover, the options for cooperation and collective organisation between farmers and other stakeholders in territories to organise and manage this diversity of land use revealed opportunities for smart social innovation. The qualitative multicriteria assessment identified farmer workload as the main issue of concern while demonstrating expected benefits of ICLS simultaneously for economic, agronomic, environmental and social criteria. This study concludes that participatory design of ICLS based on a generic multi-level and multi-domain framework and a methodology to deal with a local context can identify new systems to be tested. Further assessment and redesign work will be performed in later stages of the European FP7 CANTOGETHER project.

The relative importance of different binding mechanisms and associated biological binding agents on aggregate stability is still unclear. The aim of this study was to evaluate the role of various aggregate binding agents during the decomposition of cauliflower residues, wheat straw, cattle manure and poultry woody compost. We measured aggregate stability, hot-water extractable polysaccharide, C mineralization, fungal and microbial biomass dynamics in an amended silt loam soil, under controlled conditions. Soil aggregate stability was measured using three methods involving fast wetting, slow wetting and mechanical breakdown. Aggregate stability to slow wetting followed the same dynamics as C mineralization and was well correlated with polysaccharide content for cauliflower residues and wheat straw. This relationship is in agreement with the hypothesis that the rapid microbially induced improvement in aggregate stability that follows fresh organic residue additions at least partly involves labile polysaccharides. The transient increase in the two other types of stability was not directly related to C mineralization dynamics and seemed to be influenced by fungal hyphal length. Fungi would provide resistance to mechanical breakdown and slaking. The dynamic behaviour of biological binding agents was only partly explained by the initial quality of the organic materials, as characterized by Van Soest proximal fractionation.Dynamique de la stabilité structurale et des facteurs agrégeants biologiques associée à la décomposition de produits organiques. Résumé L'importance relative des diffe´rents me´canismes d'agre´gation et des facteurs agre´geants biologiques associe´s n'est toujours pas clairement e´tablie. L'objectif de cette e´tude est d'e´valuer l'effet de diffe´rents facteurs agre´geants sur la stabilite´structurale au cours de la de´composition de produits organiques: de re´sidus de chou-fleur, de paille de ble´, d'un fumier de bovin et d'un compost de fientes de volailles et d'e´corce de peuplier. Nous avons mesure´les dynamiques de stabilite´des agre´gats, de mine´ralisation du C et des biomasses microbienne et fongique d'un sol limoneux amende´pour des conditions controˆle´es. La stabiliteś tructurale est mesure´e par trois traitements d'intensite´s diffe´rentes correspondant a`une humectation rapide, une humectation lente et une de´sagre´gation me´canique sur des agre´gats. La stabilite´structurale soumise al 'humectation lente suit les meˆmes dynamiques que la mine´ralisation du C et est bien corre´le´e avec la concentration en polysaccharides pour les re´sidus de chou-fleur et la paille de ble´. Cette corre´lation confirme l'hypothe`se que les polysaccharides labiles participent au moins partiellement a`l'ame´lioration rapide de la stabilite´des agre´gats induite par l'activite´microbienne a`la suite d'apports de produits organiques frais. L'augmentation transitoire des deux autres types de stabilite´structurale n'est pas directement lie´e aux dynamiques de mine´ralisation du C et est plutoˆt influence´e par ...