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International audience; Soils are at the crossroads of many existential issues that humanity is currently facing. Soils are a finite resource that is under threat, mainly due to human pressure. There is an urgent need to map and monitor them at field, regional, and global scales in order to improve their management and prevent their degradation. This remains a challenge due to the high and often complex spatial variability inherent to soils. Over the last four decades, major research efforts in the field of pedometrics have led to the development of methods allowing to capture the complex nature of soils. As a result, digital soil mapping (DSM) approaches have been developed for quantifying soils in space and time. DSM and monitoring have become operational thanks to the harmonization of soil databases, advances in spatial modeling and machine learning, and the increasing availability of spatiotemporal covariates, including the exponential increase in freely available remote sensing (RS) data. The latter boosted research in DSM, allowing the mapping of soils at high resolution and assessing the changes through time. We present a review of the main contributions and developments of French (inter)national research, which has a long history in both RS and DSM. Thanks to the French SPOT satellite constellation that started in the early 1980s, the French RS and soil research communities have pioneered DSM using remote sensing. This review describes the data, tools, and methods using RS imagery to support the spatial predictions of a wide range of soil properties and discusses their pros and cons. The review demonstrates that RS data are frequently used in soil mapping (i) by considering them as a substitute for analytical measurements, or (ii) by considering them as covariates related to the controlling factors of soil formation and evolution. It further highlights the great potential of RS imagery to improve DSM, and provides an overview of the main challenges and prospects related to digital soil mapping and future sensors. This opens up broad prospects for the use of RS for DSM and natural resource monitoring.

International audience; Le changement climatique accentue les phénomènes extrêmes comme les sécheresses. À l’échelle mondiale, la concurrence pour l’usage de l’eau sera donc exacerbée. Des progrès considérables ont été réalisés récemment concernant le réservoir utile en eau des sols et ses modes d’estimation, tant dans les techniques d’évaluation de ce réservoir et de sa cartographie, que dans le suivi du stress hydrique des plantes. La vigne est un cas particulier en raison de son système de conduite et de son mode d’enracinement, ainsi que de l’influence du régime hydrique sur la qualité organoleptique et sanitaire des raisins. Sous un climat comparable, des sols très différents peuvent avoir des effets similaires sur la régulation de l’alimentation estivale de la vigne. Nous évoquons les progrès et les lacunes en matière de suivi de l’alimentation en eau de la vigne. Nous soulignons leurs possibilités et leurs limites d’extrapolation, d’utilisation et de transfert vers des outils d’aide à la décision (OAD). Nous explorons les principaux verrous de connaissance à lever en priorité et les interrogations relatives à la gestion de l’eau en contexte viticole.

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; As digital soil mapping (DSM) applications have been developed at multiple extents over the two last decades, large areas of the world are now covered by several DSM products with similar resolution and targeted soil properties. Thus, from these products, end-users must carefully select the one that will best meet their needs. The aim of this study was to evaluate three DSM products obtained at different scales (global, national and regional) over three local territories of increasing area selected in three contrasting regions of France (Alsace, Brittany and Languedoc-Roussillon). Three topsoil (5–15 cm) properties were evaluated: clay content, pH in water and soil organic carbon content. Evaluations were done at both point and soil mapping unit supports, the latter corresponding to quantitative assessment of visual accordance between DSM products and conventional local soil maps of acknowledged quality. The ability to predict soil properties well increased from global to national to regional DSM products. However, none of the DSM products tested was able to predict satisfactorily at the most local (1:25,000) scale. Evaluations of DSM products using local soil maps were generally in accordance with those using points. Evaluations using local soil maps also provided additional information about the utility of DSM products for small areas with too few soil measurements to perform punctual evaluation and for issues concerning areal-support uses of DSM products. These results suggest that when focusing on local areas, users of DSM products should evaluate their performance and, if unsatisfactory, invest in development of local DSM.

International audience; Since the beginning of 21th century, soil microbial diversity is intensively studied gathering ahuge knowledge at local and global scales. Nevertheless, the microbial habitats have beenpoorly investigated, limiting our ability to link biodiversity description and regulation. In our study,we used a pyrosequencing approach targeting 16S rRNA genes directly amplified from soil DNAto have a comprehensive view of soil bacterial and archaeal community composition across thelargest spatially explicit soil sampling available in France (2173 soils, area covered = 5.5x105km2). Based on the multivariate regression tree (MRT) method, we designed 16 distinctterrestrial microbial habitats at the territory scale, delineated by the association of soil pH, C:Nratio, land use and minorly climatic conditions. The heterogeneous spatial distribution of habitatsdrew up a complex mosaic across France. As for plants and animals, each habitat hostsgeneralist and specialist taxa and a specific interaction network, directly or indirectly impacted bythe Human activities. Overall, our results stressed the importance of the integration of microbialhabitats for upgrading the biodiversity conservation policies in a context of global change

International audience; "THE HIDDEN LIFE OF SOILS" BROCHURE AND CARD GAME : Feedback on two tools for raising awareness among young people on soil biodiversity Raising awareness among the general public, especially young people, about the importance of soils for our environment and our societies is one of the keys to their preservation. Between 2010 and 2018, the GESSOL research program "Sustainable soil management" of the French Ministry of Ecology has produced and distributed a brochure and a card game on the theme of "The hidden life of soils". These educational tools are available in French, English and Portuguese. The feedback shows that they met an expectation in the context of teaching and environmental animation. In particular, the card game is an effective awareness tool to arouse the curiosity of the young people. This confirms the interest of a playful approach around the "Biodiversity of the soils" to sensitize more generally to "Soils".