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This report desribes the co-creation experience of the ALL-Ready pilot network, which aims to set up and run a small-scale pilot network in to test the approaches, tools and recommendations developed during the project for the implementation of the future European network. As experience grows throughout the project, this document will also be updated and can be seen as a living document that will be complemented by future versions.

This paper describes the genesis and the evolution of the French Scientific Group of Interest on Soil (GIS Sol), in charge of soil inventory and monitoring. It first recalls the central role of soils for multiple issues, their mapping and monitoring at all scales. Then it describes the history of French soil mapping, from the sixties until now. It shows the links between this history and contextual changes, among which public policies and the economical contexts. It describes changes in organizational, structural and technological dimensions, and demonstrates the progress ac-complished since the 1960’s as well as some difficulties encountered. Then, it explains how this history progressively led to the creation of the GIS Sol, the genesis, launching, objectives and organization of which are described. Finally, the main reasons of its progressive enlargement, the diversification of its objectives, and of its network of members and partners are discussed., Cet article retrace la genèse et l’évolution du Groupement d’Intérêt Scientifique Sol (GIS Sol), chargé de l’inventaire et de la surveillance des sols de France. Après avoir rappelé le rôle cen-tral des sols pour de multiples enjeux et l’importance de l’information sur les sols à toutes les échelles, nous retraçons l’histoire de la cartographie des sols en France, en la replaçant dans son contexte historique, politique et économique, ainsi que dans ses évolutions organisation-nelles et technologiques. Nous montrons les progrès accomplis depuis le début des années 60, ainsi que les principales difficultés rencontrées. Nous expliquons comment cette dynamique a progressivement conduit à la création du GIS Sol, en développant la dimension temporelle, celle de la surveillance. Nous décrivons ensuite la création, les objectifs et la structure du GIS Sol, en charge de l’inventaire et de la surveillance des sols de France, puis nous montrons et expliquons les raisons de son élargissement progressif, la diversité grandissante de ses pro-grammes et de leurs applications, de ses membres et de son partenariat.

International audience; Several interdisciplinary Scientific Foresight Reflection group (SFR) were conducted between 2017 and 2019 to help update INRAE's strategic directions for 2025 in response to the major challenges of agriculture for the 21st century. Two of them have produced elements that highlight the questions and scientific fronts of knowledge related to the reconnection between crops and livestock (SFRAgroecology and SFR-Livestock). They emphasized the design of new production schemes based on the principles and concepts of ecology in order to optimize productivity, while strengthening resilience to various hazards and maximizing the services likely to be provided by agrosystems by limiting dependence on inputs. After a presentation of the research ambitions and challenges developed in each of the two SRFs, the text presents the challenges of the complementarity between culture and livestock highlighted on this occasion and details the renewal of research questions that results by considering research for genetic selection, knowledge and integration of heterogeneity and diversity at different levels, knowledge and use of abiotic and biotic processes at the landscape scale and the governance of these new systems.; Plusieurs Ateliers de Réflexion Prospective (ARP) scientifique interdisciplinaire ont été conduits entre 2017 et 2019 pour contribuer à la réactualisation des orientations stratégiques à l’horizon 2025 d’INRAE en réponse aux grands enjeux de l’agriculture pour le 21e siècle. Deux ARP ont produit des éléments permettant d’éclairer les questions et fronts de science relatifs à la complémentarité entre cultures et élevages (ARP Agroécologie et ARP Sciences pour les élevages pour demain) pour concevoir de nouveaux modes de production qui reposent sur l’utilisation des principes et concepts de l’écologie afin d’optimiser la productivité, tout en renforçant la résilience face à divers aléas, en maximisant les services susceptibles d’être fournis par les agrosystèmes et en limitant la dépendance aux intrants. Après une présentation des ambitions et enjeux de recherche développés dans chacun des deux ARP, cet article présente les enjeux de la complémentarité entre cultures et élevages mis en lumière à cette occasion et détaille le renouvellement des questionnements de recherche qui en découle, en considérant les recherches pour la sélection génétique, la connaissance et l’intégration de l’hétérogénéité au sein des parcelles et des troupeaux et de la diversité aux différents niveaux, la connaissance et l’utilisation des processus abiotiques et biotiques à l’échelle des paysages et la gouvernance de ces nouveaux systèmes.

International audience; Colloids (11000 nm) have been widely suggested as important carriers of phosphorus (P) in agricultural soils.This suggestion is, however, so far based on colloids extracted from laboratory soil solutions, with no direct fieldevidence. Here, we conducted the first field monitoring study of colloidal P (Pcoll) release and transport dynamicsin a small agricultural headwater catchment located in Western France, during one hydrological year. Resultsevidenced that Pcoll is an important fraction of the total dissolved P (TP) fraction (

International audience; Colloids (11000 nm) are important carriers of phosphorus (P) in agricultural soil solutions and have been frequentlystudied by lab extraction experiments. However, little attention has been paid so far to evaluating how theproportion and composition of P-bearing colloids were affected by the water/soil ratio and the ionic strength of theextracting solutions used. Here, we conducted lab extraction of P-bearing colloids on surface soils from two transects(G and K) located in a small agricultural catchment from Western France, at different water/soil ratios (30:1,20:1, 10:1 and 4:1) and different ionic strength (H2O, 0.001M NaCl and 0.01M NaCl), and compared the resultswith colloidal P quantification performed on natural soil solutions from the two same transects. Ultrafiltration combinedwith inductively coupled plasma mass spectrometry (UF-ICP-MS) and XANES spectroscopy were used toevaluate the proportion of colloidal P and the composition of the colloidal carriers. During laboratory extractions,we observed that total dissolved (

International audience; Stream water quality exhibits dynamics at various time scales that are controlled by the spatiotemporal dynamicsof hydrobiogeochemical compartments, particularly by the dynamics of their connectivity to the stream. Basedon long-term catchment observations from the AgrHyS Observatory (France), we established relationshipsbetween stream water quality and groundwater storage dynamics on various time scales. Those observationscombine stream water concentrations of Dissolved Organic Carbon (DOC), Nitrates (NO3) and Phosphorus (SRP)concentrations, and a network of piezometers along 2 transects to characterize groundwater storage and quality inspace and time.At the annual scale, the rise of groundwater table is delayed between the riparian area (early autumn) andthe upslope area (winter). This time lag along the hillslope is identified as the dominant control of the seasonalsignal in stream base flow nutrient concentrations.-DOC and SRP are mobilized from organic upper soils layers when reached by the groundwater table. Firstly,groundwater table rises in the riparian area, and connects the C and P sources in the organic rich riparian soilsleading to high stream DOC and SRP concentrations. Then, while groundwater connectivity remains high inthe riparian area, these sources are depleted leading to a progressive decrease in stream base flow DOC andSRP concentration. In the recession and low flow periods, shallow groundwater contribution decreases and otherprocesses can influence stream concentrations.-NO3 are mobilized from upslope shallow groundwater and therefore nitrate annual dynamics follows the annualfluctuations of catchment water storage. At the start of the water year, the water table rise in the denitrified riparianarea leads to low stream nitrate concentrations. Then, the water table rise in the upslope area leads to suddenincrease in stream nitrate concentration. In the recession period, the nitrate concentration decreases variablydepending on the dynamics of the groundwater recession, itself controlled by climate and vegetation demand.Groundwater dynamics appear to control concentration dynamics not only during base flow period but alsoduring storm events. Most of the storms occur during winter when groundwater is high and sub-surface connectivitymaximal. Conversely, the events that occur during dry periods can depict very different stream concentrationresponse because of reduced subsurface connectivity due to deeper groundwater table, leading to more variablestorm flowpaths.The two studied hillslopes show contrasting groundwater nitrate concentrations, soil organic matter andsoil phosphorus content. These differences are mainly attributed to the difference in soils-groundwater interactionsand in past and current farming practices.This conceptual model of the effect of spatio-temporal variations of groundwater table depth on soil andstream water quality highlights the importance of shallow groundwater in controlling the non-stationarity and thespatial variability of water quality response in catchments. This offer new constrains for modelling water qualityat different time scales.

Special section: Continuous nutrient sensing in research and management: applications and lessons learned across aquatic environments and watersheds; International audience; We tested an empirical modeling approach using relatively low‐cost continuous records of turbidity and discharge as proxies to estimate phosphorus (P) concentrations at a subhourly time step for estimating loads. The method takes into account nonlinearity and hysteresis effects during storm events, and hydrological conditions variability. High‐frequency records of total P and reactive P originating from four contrasting European agricultural catchments in terms of P loads were used to test the method. The models were calibrated on weekly grab sampling data combined with 10 storms surveyed subhourly per year (weekly+ survey) and then used to reconstruct P concentrations during all storm events for computing annual loads. For total P, results showed that this modeling approach allowed the estimation of annual loads with limited uncertainties (≈ −10% ± 15%), more reliable than estimations based on simple linear regressions using turbidity, based on interpolated weekly+ data without storm event reconstruction, or on discharge weighted calculations from weekly series or monthly series. For reactive P, load uncertainties based on the nonlinear model were similar to uncertainties based on storm event reconstruction using simple linear regression (≈ 20% ± 30%), and remained lower than uncertainties obtained without storm reconstruction on weekly or monthly series, but larger than uncertainties based on interpolated weekly+ data (≈ −15% ± 20%). These empirical models showed we could estimate reliable P exports from noncontinuous P time series when using continuous proxies, and this could potentially be very useful for completing time‐series data sets in high‐frequency surveys, even over extended periods.

International audience; Riparian vegetated buffer strip (RVBS) are currently used to protect surface waters from phosphorus (P) emissionsbecause of their ability to retain P-enriched soil particles. However, this protection role may be counterbalancedby the development in these zones of conditions able to trigger the release of highly mobile dissolved or colloidalP forms. Rewetting after drying is one of these conditions. So far, the potential sources of P mobilized duringrewetting after drying are not clearly identified, nor are clearly identified the chemical nature of the releaseddissolved P species, or the role of the soil P speciation on these forms. In this study, two riparian soils (G andK) showing contrasting soil P speciation (65% of inorganic P species in soil G, as against 70% of organic P)were submitted to three successive dry/wet cycles in the laboratory. Conventional colorimetric determination ofP concentrations combined with ultrafiltration, and measurements of iron (Fe) and aluminum (Al) and dissolvedorganic carbon (DOC) contents using ICP-MS and TOC analyzers, respectively, were used to study the responseof the different P forms to rewetting after drying and also their release kinetics during soil leaching.For both soils, marked P release peaks were observed at the beginning of each wet cycles, with the organic-rich Ksoils giving, however, larger peaks than the inorganic one (G soil). For both soils also, concentrations in molybdatereactive P (MRP) remained quite constant throughout each leaching episode, contrary to the molybdate unreactiveP (MUP) concentrations which were high immediately after rewetting and then decreased rapidly during leaching.A speciation change was observed from the beginning to the end of all leaching cycles. Colloidal P was found tobe a major fraction of the total P immediately after rewetting (up to 50-70%) and then decreased to the end of eachwet cycle where most of the eluted P was true dissolved inorganic P. Colloidal-P exhaustion was tightly associatedwith DOC, Fe and Al exhaustions. Colloids were larger in size at the beginning than at the end of all cycles. Peakat the beginning of each wet cycles remained quite constant even after two drying/leaching cycles, evidencing theexistence of mechanisms able to rebuild a pool of leachable P during drying process.Thus, there was clearly a control of soil characteristics on the released P forms in leachates. Colloidal P carriersappeared to consist of Fe and/or Al oxyhydroxide nano/microparticles associated with organic matter. Mostimportantly, a survey of colloidal size distribution during leaching indicated that the rapidly exhausted MUP poolconsisted of larger size MUP and colloidal P phases, which probably originated from soil macropores, while therelatively infinite MRP pool consisted of smaller size colloidal P and true dissolved MRP phases, which wasmobilized from soil micropores. These results further demonstrate the ability of rewetting after drying to lead topulses of dissolved and colloidal P in riparian soils, thereby evidencing the risks that P-enriched soil particlesaccumulated in RVBS could constitute a long-term threat for surface water