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Monitoring pH and P K MG levels in French soils between 2003 and 2020 using the French soil analysis database (base de données des analyses de terre)
No full textInternational audienceThe continuing rise in energy prices is affecting fertilizer prices, and is accompanied by a general reduction in phospho-potassium fertilization of agricultural plots nationwide. In France, since 1990, the Base de Données des Analyses de Terre (BDAT INFOSOL INRAE Orléans) has brought together the results of soil tests of cultivated topsoil carried out throughout mainland France, at the request of farmers, by laboratories approved by the Ministry of Agriculture. This database contains over 3 million phosphorus (P) determinations and an equivalent number of exchangeable potassium (K) and magnesium (Mg) determinations. These data were mobilized as part of a spatio-temporal diagnosis to provide information on the spatio temporal trends of these three fertility parameters over the period 1990-2020, and to identify the consequences on the availability of these elements for crops.General trends in the evolution of agricultural soils in mainland France show an increase in pH and Mg content, and a decrease in K, but especially P, content. The spatial distribution of exchangeable P Olsen, K and Mg contents in soils seems to depend mainly on soil characteristics (texture, mineralogical nature of parent materials). The temporal trends observed for Olsen P and exchangeable K, on the other hand, seem to depend on economic factors (rising energy and fertilizer prices), the presence or absence of livestock farming, and recommendations for lower dose calculations as part of a rational fertilization approach.This work demonstrates the importance of collecting and collating this information, produced in an individual context for plot management, in order to reuse it in a general context and produce results on the statistical distributions of agricultural soil fertility indicators. However, these preliminary results should be treated with caution and should not be used for the fertilization of agricultural plots
Etude des principaux freins et leviers à la conversion et à l'installation en agriculture biologique des élevages porcins français du point de vue des éleveurs
No full textNational audienceOnly 1.8 % of French sows are certified organic. Consequently, a study was performed to understand the obstacles to and mechanisms for conversion to and installation of organic farming on French pig farms. Interviews were conducted in 2020 with four organic pig farmers and seven conventional pig farmers in southern France and in Brittany (northwestern France). The results of these interviews were used to construct a decision tree that summarized the mental path taken by a pig farmer when deciding whether to convert to organic farming or not. The main obstacle was the farmer's pre-existing opinion of the organic sector. One associated mechanism for addressing it was to increase dissemination of knowledge about the organic pig sector in agricultural training courses. The second obstacle was the uncertainty of outlets, related to the high price of organic pork. The associated mechanisms were to decrease the sales price and production costs, in particular by encouraging feed production on the farm and developing on-farm processing and direct sales, even if doing so changes the farmer's job and greatly increases the workload and investment required. Other obstacles to conversion to organic pig farming were identified, such as concerns about access to local organic feed ingredients and the availability of organic piglets. These obstacles echoed farmers' concerns about the profitability of their farms and their working time. The farmers also reported a lack of consistency by consumers, who want to eat locally but do not want pig farms close to their homes
Compréhension des mécanismes de formations des agrégats protéiques en solution sous l'effet du cisaillement
No full textLicenceL’objectif du stage a été de d’évaluer l’impact de la concentration et du cisaillement sur la dénaturation et l’agrégation des protéines sériques du lait en solution, afin de mieux comprendre l’encrassement des matrices laitières dans des évaporateurs à flot tombants pendant la concentration par évaporation. Des solutions d’isolat de protéines sériques à 5, 10 et 12 % p/p ont été préparées et cisaillées aux taux de cisaillements différents (0, 50, 100 et 175 s-1), à 65 °C pendant 10 min, en utilisant un rhéomètre et une géométrie cône/plan. Les analyses chromatographiques, colorimétriques et spectroscopiques des solutions traitées ont permis de conclure sur un effet prédominant de la concentration en protéines sur leurs dénaturation et agrégation car le taux de dénaturation et l’agrégation indirectement observéeont augmenté avec l’augmentation de la concentration en protéines. Néanmoins, l’impact du cisaillement sur ces phénomènes a été peu significatif. En perspective, en comparant ces résultats à ceux qui ont été obtenus à l’interface solution/surface, il serait possible de mieux comprendre les mécanismes de formation des dépôts protéiques sous l’action du cisaillement
Ferments, Ils vont révolutionner la nourriture du futur
No full textNational audienceEn consommation croissante, les produits fermentés constituent désormais une sérieuse solution de transition vers une alimentation moins carnée et moins sucrée. Un nouveau centre de recherche en région parisienne va explorer ce monde encore méconnu des bactéries, levures et champignons
Evolution de représentations contemporaines de la nature de deux zones humides littorales et de leur paysage du XXe au XXIe siècles
No full textInternational audienceCoastal landscapes are influenced by many changes in their landscape dynamics. This article discusses about the evolution of representations of two coastal wetlands currently protected for their nature, and their interdependence with landscape formation. From iconographic documents, we notice that representations of nature changed between the XXe and XXIe centuries, linked to societal and cultural shiftsLes paysages littoraux sont marqués par de nombreux changements dans leur dynamique paysagère. Cet article s’intéresse à l'évolution des représentations de deux zones humides littorales protégées et leur interdépendance avec la construction de leur trajectoire paysagère. A partir de sources iconographiques, on constate qu'entre le XXe et le XXIe siècle les représentations de nature de ces sites ont changé en lien avec les évolutions sociétales et culturelles
Minimal processed infant formula vs conventional shows comparable protein quality and increased postprandial plasma amino acid kinetics in rats
No full textInternational audienceDuring industrial processing, heat treatments applied to infant formulas may affect protein digestion. Recently, innovative processing routes have been developed to produce minimally heat-processed infant formula. Our objective was to compare the in vivo protein digestion kinetics and protein quality of a minimally processed (T-) and a heat-treated (T+++) infant formula. Sixty-eight male Wistar rats (21 days) were fed with either a diet containing 40% T- (n=30) or T+++ (n=30), or a milk protein control diet (n=8) during 2 weeks. T- and T+++ rats were then sequentially euthanized 0, 1, 2, 3, or 6 h (n=6/time point) after ingestion of a meal containing their experimental diet. Control rats were euthanized 6 h after ingestion of a protein-free meal to determine nitrogen and amino acid endogenous losses. Nitrogen and amino acid true cecal digestibility was high for both T- and T+++ diets (> 90%), but a tendency toward higher nitrogen digestibility was observed for the T- diet (96.6 ± 3.1%) compared to the T+++ diet (91.9 ± 5.4%, P=0.0891). This slightly increased digestibility led to a greater increase in total amino acid concentration in plasma after ingestion of the T- diet (P=0.0010). Comparable protein quality between the two infant formulas was found with a Digestible Indispensable Amino Acid Score (DIAAS) of 0.8. In conclusion, this study showed that minimal processing routes to produce native infant formula do not modify protein quality but tend to enhance its true nitrogen digestibility and increase postprandial plasma amino acid kinetics in rats
Lignes directrices pour l’élaboration de listes d’espèces végétales et fongiques des milieux terrestres, aquatiques et littoraux à proposer à la protection
No full textClés de sol : un projet de sciences et recherches participatives.
No full textInternational audienceLe projet Clés de Sol est un projet de sciences et recherches participatives (SRP) sur la connaissance des sols, en particulier des propriétés intrinsèques des sols (propriétés pédologiques relativement stables dans le temps). Il vise à enrichir les bases de données sur les sols, à développer les méthodes de cartographie des sols aux échelles territoriales à partir d’informations hétérogènes, tout en contribuant à propager dans la société une meilleure connaissance des sols et des enjeux dont ils sont porteurs. La première phase du projet, financée dans le cadre de l’appel à projet CO3 (2019-2022), avait pour objectifs de i) stabiliser les protocoles participatifs par des tests sur 8 sites divers se distinguant par les structures d’animation et le contexte pédologique ; ii) tester la qualité des informations collectées par des non experts et créer les supports pédagogiques nécessaires pour l’accompagnement, la mise en œuvre ; iii) préparer la phase de déploiement du projet.A l’issue de la première phase du projet, des perspectives ont été dressées à trois niveaux : 1) celui de tirer les enseignements sur les travaux réalisés (passer des propriétés des sols à des enseignements qui font sens pour les bénévoles ; simplifier plus encore les protocoles, ou en proposer deux niveaux...) ; 2) celui de poursuivre le projet par le déploiement sur deux territoires de démonstration, avec des partenaires locaux plus impliqués et en lien avec des enjeux locaux ; 3) celui de tirer parti des dynamiques actuelles sur les approches de sciences participatives sur le sol issues d’autres projets (reprendre certains protocoles, certains outils…). Le projet Clés de Sols 2 (2023-2025) financé par l’ADEME propose de répondre à ces perspectives.Pour ce faire, notre démarche s’appuie sur le déploiement d’une recherche participative sur les sols sur deux démonstrateurs territoriaux, mettant en œuvre une offre enrichie et concertée de caractérisation des sols faisant sens pour les animateurs et bénévoles de ces territoires
Spider community in cereal–legume association
No full textInternational audienceSpiders are a major and rich community of generalist natural predators in agricultural landscapes. This community has the potential to provide general and simultaneous natural regulation of several crop pests, depending on the species present and their ecological traits. Many factors can influence their community composition and abundance, and this knowledge could enable us to better assess, predict and manipulate their contribution as crop auxiliaries. Here, we study the spider community living in cereal-legume fields, a mixed crop that is currently a major challenge in France, as it could make it possible to offset soybean imports, but suffers from multiple pest damage. We describe spider community at different time in the cropping season and at different place in the field (at the border or in the center) and in multiple conventional and organic fields of faba beans-cereal. We make the link between the functional groups of spiders present and their potential involvement in prey consumption, especially of crop pests (aphids, bruchids and sitones)
Dernière étape avant la mise en œuvre d'un suivi complet de la biodiversité des sols en France
No full textInternational audienceDespite its improtance for human activities, soil biodiversity remains largely unknown and threatened. The French Soil Quality Monitoring Nerwork (RMQS) has a significant impact in removing the grey areas through its survey of soil microorganisms and enzymatic activities.These surveys have deepened our knowledge of the biogeographyof microorganisms, the link with soil use and agricultural pratices, and identified bioindicators of soil quality. But the RMQs could also support long-term monitoring of other components of soil biodiversity.In 2017, the French office for biodiversity expressed the need to buid a survey of soil biodiversity, which will be part of the larger survey of terrestrial biodiversity.A first experimentation based on the monitoring of 30 RMQS sites around France started in 2019, taking into account scientific and practical aspects. Biodiversity sampling was carried out all year long, by the same 12 teams as for the RMQS program, simultaneously with soil sampling and description. Bacteria, fungi and protists were monitored by DNA extraction and sequencing, as well as environmental DNA. Nematodes, mesofauna (particularly springtails), below-ground (earthworms) and surface (beetles and spiders) macrofauna were monitored by sampling and identification of specimens. This study demonstrated the feasibility of monitoring all components of soil biodiversity and lead to the writing of a manual of specifications. However, contrasting to soil microorganisms which can be monitored all along the year, results showed that soil fauna should be monitored during spring.In spring 2024, a second experimentation based on the monitoring of 72 sites will start, involving 3 soil biodiversity experts teams to monitor the same groups as in the first test, from March to June. This experimentation will assess the feasibility of sampling more sites during a shorter period of time. The objective would be to reach the sampling of 180 sites per year, i.e. the routine level of sampling of the second RMQS campaign, to implement a comprehensive monitoring of soil biodiversity for French soils