Landscape design for soil conservation under land use and climate change

International audienceSoils and landscapes evolve simultaneously. Soil evolution is controlled by redistribution and transformation processes influenced by topographic and climatic parameters, with also a major contribution of management strategies. The perennial landscape features have a strong influence on soil spatial distribution (geometry) and soil genesis. Building landscapes which enhance soil resilience to degradation processes and increase soil services appears as a promising way to adapt to forthcoming climatic and land use evolutions. The presentation aims to synthetize major results from a research program nicknamed Landsoil which focused on the evolution of agricultural soils over medium time scales (decades to centuries) in relation to changing conditions of land use and climate. Precise study of the soil 3D organization in three contrasted landscapes (Brittany, Touraine, Languedoc-Roussillon) enabled to link soil redistribution in space to landscape components (field geometry, hedges or ditches network) and their past evolution. A dynamic and high resolution spatial modeling approach was developed coupling erosion processes and soil organic matter evolution and was calibrated over past evolution using dating techniques (Cs137, C14, OSL). The resulting Landsoil model was afterwards applied in a prospective manner under different scenarios of land use and climate change over the 21th century. Indicators of soil vulnerability and soil resilience were defined and tested by the comparison of several prospective scenarios applied on a same landscape and by comparison of the contrasted landscapes

Les cryoglobulinémies non liées au virus de l'hépatite C au centre hospitalier de Mulhouse

STRASBOURG-Medecine (674822101) / SudocPARIS-BIUM (751062103) / SudocSudocFranceF

Habiter et mieux vivre dans les non-lotis !: Fédérer les habitant.es du quatier précaire Doassa (Burkina Faso, Ouagadougou) pour leur donner accès à un habitat digne

International audienceFinancé par la Fondation Abbé Pierre et l’Agence française de développement, le projet « Habiter et mieux vivre dans les non-lotis ! » a été mené de 2020 à 2022 par l’association Yaam Solidarité et ses partenaires au Burkina Faso. L’objectif principal de ce projet était d’améliorer les conditions d’accès à un habitat décent dans le quartier non-loti (quartier informel) de Boassa à Ouagadougou en fédérant les habitant.es dans le processus de rénovation urbaine. Yaam Solidarité a mené une démarche de diagnostic et de planification concertée tout en renforçant les capacités locales de gestion territoriale. L’association s’est appuyée sur les instances citoyennes et les initiatives de développement local qu’elle a soutenues dans leur organisation. Le projet comportait un volet « multi-pays » qui a permis une concertation avec d’autres organisations travaillant sur les mêmes sujets : le Grdr en Guinée-Bissauet UrbaSEN au Sénégal. Ce partage d’expériences sur la production sociale de l’habitat a permis de mutualiser des connaissances, d’enrichir la réflexion et de développer des éléments théoriques et méthodologiques

Quantification et modélisation de l’impact des remembrements parcellaires et des bordures de parcelles sur la redistribution des sols des versants cultivés

National audienc

Impact of land consolidation and field borders on soil erosion and storage within agricultural landscapes

International audienceSoil erosion plays an important role in sediment and carbon storage within, and exports from, catchments. In cultivated landscapes, field borders can improve the temporary storage of eroded soil particles and associated carbon, by impeding lateral soil fluxes. These local soil accumulations can lead to the development of linear landforms (such as headlands and lynchets) which will keep evolving after field border removal. A recent study performed in a representative cultivated hillslope of the SW Parisian Basin showed that 39% of the area corresponds to landforms resulting from soil accumulation induced by former and present field borders. This study demonstrated that field borders influence greatly the landscape morphology, but also the spatial distribution of soil thickness, and locally the A-horizon thickness, which are essential parameters for the prediction of SOC stocks. This study aims at characterizing and quantifying the effect of field borders and their removal on medium term topsoil erosion and deposition rates in a cultivated hillslope of the SW Parisian Basin, consolidated in 1967. Here, we used the Cs-137 technique to assess recent patterns of soil redistribution. We measured the Cs-137 inventories of 68 soil cores sampled along transects covering the area and, more specifically, linear landforms identified along present and past field borders (i.e. lynchet and undulation landforms, respectively). Then, we used a spatially-distributed Cs-137 conversion model that simulates and discriminates soil redistribution induced by water and tillage erosion processes over the last fifty years. Finally, observations and model outputs were confronted. Our results show that tillage erosion dominate the soil redistribution in the study area for the 1954-2009 period and generated about 95% (i.e. 4.50 Mg.ha −1 .yr −1) of the total gross erosion. Soil redistribution was largely affected by the presence of current and former field borders, where hotspots areas of deposition and erosion (>20 Mg.ha −1 .yr −1), respectively, were observed. Land consolidation contributed to the local acceleration of topsoil erosion through the conversion of storing areas into sediment generating areas. Though the general patterns of Cs-137 inventories in the area were correctly reproduced by the model, this latter performed weakly with a r2 of 0.20. Important discrepancies were associated with sampling points located along current field borders where data suggests that tillage erosion processes cannot be described as elsewhere, i.e. as a diffusive process. These specific processes implied here should be characterised and implemented into erosion models for simulating rates and patterns of topsoil redistribution in fragmented cultivated landscapes. In addition, the use of a DEM of the present-day morphology leads to the underestimation of soil erosion and storing within linear landforms which morphology seems to have greatly evolved since 1967. This study highlights the importance of present and former field borders on the patterns and intensities of topsoil erosion and deposition processes at landscape scale. This is of particular interest concerning the improvement of our knowledge on soil organic carbon patterns and on estimation of SOC stocks

Quantifying and modelling the impact of land consolidation and field borders on soil redistribution in agricultural landscapes (1954–2009)

Soil erosion rates in cultivated areas have intensified during the last decades leading to both on and off-site problems for farmers and rural communities. Furthermore, soil redistribution processes play an important role in sediment and carbon storage within, and exports from, cultivated catchments. This study focuses on the impact of land consolidation and changes in landscape structure on medium term soil erosion and landscape morphology within a 3.7-ha field in France. The area was consolidated in 1967 and we used the Cs-137-technique to quantify soil erosion for the period (1954-2009). We measured the Cs-137 inventories of 68 soil cores sampled along transects covering the entire area and especially specific linear landforms located along both present and past field borders (i.e., lynchets and undulations landforms, respectively). These results were then confronted with the outputs of a spatially-distributed Cs-137 conversion model that simulates and discriminates soil redistribution induced by water and tillage erosion processes. Our results showed that tillage processes dominated the soil redistribution in our study area for the last 55 years and generated about 95% (i.e., 4.50 Mg.ha(-1).yr(-1)) of the total gross erosion in the field. Furthermore, we demonstrated that soil redistribution was largely affected by the presence of current and also former field borders, where hotspots areas of erosion and deposition (>20 Mg.ha(-1).yr(-1)) were concentrated. Land consolidation contributed to the acceleration of soil erosion through the conversion of depositional areas into sediment generating areas. Although the conversion model was able to reproduce the general tendencies observed in the patterns of Cs-137 inventories, the model performance was relatively poor with a r(2) of 0.20. Discrepancies were identified and associated with sampling points located along the current field borders. Our data suggests that tillage erosion processes near field boundaries cannot be described as a typical diffusive process. These processes near field boundaries should be characterised and taken into account in a future version of the model to accurately simulate rates and patterns of past soil redistribution in fragmented cultivated hillslopes. We also showed that the use of an accurate DEM resulting from LIDAR data, based on present-day topography, leads to the underestimation of soil redistribution rates by the model, especially in this landscape submitted to recent and important morphological changes. Our results have important implications for the simulation of tillage erosion processes and our understanding of soil redistribution processes in complex cultivated areas. This is of particular interest to improve our knowledge and prediction of patterns of soil physical parameters, such as carbon storage or water content, particularly sensitive to surface erosion and landscape structuration. Anglai

Deciphering of six blocks of Gondwanan origin within Eastern Indonesia (South East Asia)

The French Indonesian research programs, both conducted on land and offshore in the Banda Sea basins area, have led us to formulate a new interpretation of the East Indonesian geological components. In this area we distinguish, within the three main tectonic plates (Eurasian, Indo-Australian and Philippine–Pacific), seven blocks. Six blocks are deciphered as issued from the north-eastern Gondwanan margin and only one (the Halmahera block) issued from the Pacific plate. Among the Gondwanan blocks, two of them, namely Timor(probably originates from “Greater India”) and Kolonodale (or the Argo block) came from the north-west Australian margin. The Lucipara, Seram and Banggai–Sula blocks originated from the western extension of the Papua-NewGuinea Island while the Irian Jaya block is still linked to the North Australian margin. The last one, the Halmahera block, originated fromthe Pacific plate, moved westward along the North Papua-New-Guineamargin up to its present position in the northern part of the Banda Sea area. Our interpretation is mainly based on the lithostratigraphic succession, the geological evolution and the Early Mesozoic paleoposition of these blocks with respect to the climatic environment deduced from micropaleontological studies. According to previous studies, the Timor and Kolonodale blocks were detached from Gondwana during the Jurassic whereas the Lucipara, Seram and Banggai–Sula blocks were detached from Papua-New Guinea Island during theNeogene period. All these Gondwanan blocks collided with the Eurasian active margin, in the vicinity of Sulawesi Island: Timor and Kolonodale had joined the Eurasian margin by the end of the Paleogene, while Lucipara, Seram and Banggai–Sula collided with Sulawesi Island between the MiddleMiocene to Middle Pliocene. After the collisions the last three blocks together with the Kolonodale block did not move again but suffered the opening of North and South Banda back-arc basins, by the Late Miocene. On the contrary, part of the Timor block moved south together with the southern margin of the south Banda basin and, later on during the middle Pliocene,collided with the northern Australian margin. The detachment of these blocks from the Gondwana margin, and their amalgamation with the Eurasian margin, are discussed and illustrated through palaeogeographic maps

Exploring necrotizing autoimmune myopathies with a novel immunoassay for anti-3-hydroxy-3-methyl-glutaryl-CoA reductase autoantibodies.

International audienceINTRODUCTION: Necrotizing autoimmune myopathies (NAM) have recently been defined as a distinct group of severe acquired myopathies, characterized by prominent myofiber necrosis without significant muscle inflammation. Because of the lack of appropriate biomarkers, these diseases have been long misdiagnosed as atypical forms of myositis. NAM may be associated to autoantibodies directed against signal recognition particle (SRP) or 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCR). The objective of this work was to quantify anti-HMGCR autoantibodies in patients with suspicion of NAM through the development of a new addressable laser bead immunoassay (ALBIA). METHODS: Recombinant HMGCR C-domain was bound to fluorescent beads. After incubation with serum, autoantibodies were revealed using class- or subclass-specific anti-human immunoglobulin G (IgG) antibodies. Anti-HMGCR levels were assayed in 150 patients with suspicion of NAM, 142 controls with different inflammatory/autoimmune diseases and 100 healthy donors. Inhibition with free recombinant HMGCR and immunoprecipitation experiments confirmed test specificity. Reproducibility and repeatability were determined from sera with various levels of anti-HMGCR autoantibodies. A multiplex assay (ALBIA-NAM) was also developed to permit the simultaneous quantification of anti-HMGCR and anti-signal recognition particle autoantibodies. RESULTS: No controls scored positive. Of 150 patients with suspicion of NAM, 24% were positive for anti-HMGCR autoantibodies with levels ranging from 24 to 2,656 AU/mL. Anti-HMGCR positivity could be associated to a cytoplasmic pattern in immunofluorescence assay on HEp-2 cells. Anti-HMGCR-positive patients had high creatine kinase (CK) levels (mean 6,630 IU/L) and only 40% of them had been exposed to statins. Multiplex ALBIA-NAM was equally as effective as monoplex anti-HMGCR and anti-SRP ALBIA. CONCLUSIONS: Both monoplex ALBIA-HMGCR and multiplex ALBIA-NAM reliably detect and quantify anti-HMGCR autoantibodies. A positive result allows ascribing patients with a necrotizing myopathy to an autoimmune form. Anti-HMGCR autoantibodies may be found in patients who have not taken statins

Terroir Influence on Polyphenol Metabolism from Grape Canes: A Spatial Metabolomic Study at Parcel Scale

International audienceThe composition of bioactive polyphenols from grape canes, an important viticultural byproduct, was shown to be varietal-dependent; however, the influence of soil-related terroir factors remains unexplored. Using spatial metabolomics and correlation-based networks, we investigated how continuous changes in soil features and topography may impact the polyphenol composition in grape canes. Soil properties, topography, and grape cane extracts were analyzed at georeferenced points over 3 consecutive years, followed by UPLC-DAD-MS-based metabolomic analysis targeting 42 metabolites. Principal component analyses on intra-vintage metabolomic data presented a good reproducibility in relation to geographic coordinates. A correlation-driven approach was used to explore the combined influence of soil and topographic variables on metabolomic responses. As a result, a metabolic cluster including flavonoids was correlated with elevation and curvature. Spatial metabolomics driven by correlation-based networks represents a powerful approach to spatialize field-omics data and may serve as new field-phenotyping tool in precision agriculture

Granulomatous Myositis: Heterogeneity and Response to Treatment

International audienc