AgroParisTech
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Recent publications
The estimation of irrigation water requirements (IWR) amount and timing is crucial for designing water management strategies at the regional scale. Irrigation requirements can be estimated with different types of models: very complex and detailed crop models, agent-based models, or simplified modeling approaches. Because simplified approaches are often preferred, in this study, we evaluate the consequences of using simplified approaches for IWR assessment at a catchment scale and the consequences of various modeling choices, providing information on the uncertainties. To this end, different simple modeling approaches based on the CropWat model are compared with an agent-based approach (MAELIA), which serves as a benchmark. To assess simulations in detail, partial variance is calculated for several indicators characterizing daily simulated irrigation. Our sensitivity analysis, applied over a sub-catchment of the Aveyron River (southwestern France), shows a high variability in simulations produced by CropWat between the modeling assumptions tested, principally explained by the rules for irrigation triggering and the quantification of daily irrigation. The analysis also shows that several simplified approaches are able to reproduce the irrigation simulated by the high-accuracy MAELIA model, but not necessarily corresponding to an optimal irrigation scheme. Hence, this study confirms the possibility of assessing daily irrigation with simplified approaches, but warns about high modeling uncertainties, reflecting uncertainty in effective irrigation practices. This uncertainty can be taken into account by water managers and modelers through the combination of a set of irrigation models.
Global change may have profound effects on soil nitrogen (N) cycling that can induce positive feedbacks to climate change through increased nitrous oxide (N2O) emissions mediated by nitrification and denitrification. We conducted a meta‐analysis of the effects of elevated CO2 on nitrification and denitrification based on 879 observations from 58 publications and 46 independent elevated CO2 experiments in terrestrial ecosystems. We investigated the effects of elevated CO2 alone or combined with elevated temperature, increased precipitation, drought, and N addition. We assessed the response to elevated CO2 of gross and potential nitrification, potential denitrification, and abundances of related functional genes (archaeal amoA, bacterial amoA, nirK, nirS, and nosZ). Elevated CO2 increased potential nitrification (+28%) and the abundance of bacterial amoA functional gene (+62%) in cropland ecosystems. Elevated CO2 increased potential denitrification when combined with N addition and higher precipitation (+116%). Elevated CO2 also increased the abundance of nirK (+25%) and nirS (+27%) functional genes in terrestrial ecosystems and of nosZ (+32%) functional gene in cropland ecosystems. The increase in the abundance of nosZ under elevated CO2 was larger at elevated temperature and high N (+62%). Four out of 14 two‐way interactions tested between elevated CO2 and elevated temperature, elevated CO2 and increased precipitation, and elevated CO2 and N addition were marginally significant and mostly synergistic. The effects of elevated CO2 on potential nitrification and abundances of bacterial amoA and nirS functional genes increased with mean annual temperature and mean annual precipitation. Our meta‐analysis thus suggests that warming and increased precipitation in large areas of the world could reinforce positive responses of nitrification and denitrification to elevated CO2 and urges the need for more investigations in the tropical zone and on interactive effects among multiple global change factors, as we may largely underestimate the effects of global change on soil N2O emissions.
Mammalian newborns depend on their mother’s milk to satisfy their initial needs of protection and nutrition. They reach the source of milk in following visual, tactile and olfactory cues. In particular, parturient ewes produce an odorous wax in the inguinal glands close to the teats. When presented separately to newly born lambs, this inguinal wax (IW) elicits arousal, head orientation, licking and increased respiratory rate indicative of their avidity for it. The present study assessed whether transferring IW into the environment of artificially fed lambs would improve their responses to the novelty of the situation. We first assessed whether suckled lambs preferred an IW-scented teat to a scentless control teat. Then, we assessed whether a teat odorized with IW was more easily learned as suckable relative to a control teat. Finally, the lambs’ growth performance from postnatal days (PND) 0 and 20 was compared in groups reared with or without IW spread on the milk-feeder in their home pen. The behavioral assays did not evidence any significant effect of IW odor on previously suckled lambs’ attraction and appetence responses. However, relative to the scentless control condition, being exposed to an IW-smeared milk-feeder led to a higher body weight at 20 days after birth. In the conditions of the present study, namely after suckling initiation, IW odor appeared not to be a strong determinant of short-term attraction or appetitive behavior in neonate lambs. The continued presence of IW, a familiar odor, in the artificial suckling context may improve artificially-reared lambs’ emotional state that may affect their weight gain.
Most bread wheat is consumed after processing, which mainly depends on the quantity and quality of protein in the grain. Storage protein content and composition particularly influence the end use quality of milled grain products. Storage proteins are components of the gluten network that confer dough viscoelasticity, an essential property for processing. To explore grain storage protein diversity, 75 bread wheat accessions were grown with two replicates each at two locations. Grains were harvested at maturity and samples were phenotyped for each site and each replicate plant. Grain hardness, thousand-kernel weight and grain nitrogen content were measured. The protein composition of flour from each replicate was characterised by reverse phase-high performance liquid chromatography (RP-HPLC). The molecular distribution of flour polymers was determined by asymmetric flow field-flow fractionation (AF4) and dough technological properties were assessed using a Glutomatic system and a Chopin alveograph. In addition, the 75 accessions were genotyped by the BreedWheat 35k genotyping array (Axiom TaBW35K) containing 34,746 single nucleotide polymorphism markers (SNPs). The dataset produced by this work includes six files with raw data, two files with protocols and figures. Data show the genotypic and phenotypic variabilities of the material used and can be used to explore genetic and environmental effects on traits involved in grain protein quality. This dataset is associated to the research article “Differences in bread protein digestibility traced to wheat cultivar traits” [1].
Whilst the re-introduction of fire can contribute to biodiversity conservation in Fennoscandian forests, the effects on reindeer herding remain uncertain. To assess the short- and long-term effects of prescribed burning on lichen supply in a productive forest landscape, we developed a model simulating lichen biomass available for reindeer grazing, covering 300 years and 1500 pine stands, under different soil preparation scenarios, including different prescribed burning regimes and mechanical scarification. Our simulations revealed that burning 25–50% of yearly clear-cuts has the potential to stop, or even reverse, reindeer lichen decline at landscape scale after 70 years, greatly surpassing the short-term losses caused by burning. No burning or burning 5% of yearly clear-cuts, as required by the FSC certification, compounded the negative effects of fire suppression and scarification on lichen. Compared to the scenario with no soil preparation, all our simulations resulted in a continuous decrease of lichen supply in Lichen-type stands, indicating that any form of disturbance in these habitats can strongly limit future gains.
This article develops a multiscale institutional framework to shed light on the territorial dynamics of a sector. The case of the long-term transformation of the European dairy industry shows that, within a common European regulatory system, sectoral communities are structured territorially in Germany and nationally in France. Second, a change in public policies exerts pressure not only on firms’ adaptation capacities but also on sectoral communities. Third, territorial institutions appear primary in structuring sectoral dynamics when territorial players (public, private and collective) create, pool and sustainably manage productive resources, either for integration into a wider market or for developing a local means of competing.
Compared to bacteria of the gut microbiota, bacteriophages are still poorly characterized, and their physiological importance is far less known. Temperate phages are probably a major actor in the gut, as it is estimated that 80 % of intestinal bacteria are lysogens, i.e. they are carrying prophages. In addition, prophage induction rates are higher in the gut than in vitro. However, studies on the signals leading to prophage induction have essentially focused on genotoxic agents with poor relevance for this environment. In this review, we sum up recent findings about signals able to trigger prophage induction in the gut. Three categories of signals are at play: those originating from interactions between intestinal microbes, those from the human or animal host physiology and those from external intakes. These recent results highlight the diversity of factors influencing prophage induction in the gut, and start to unveil ways by which microbiota composition may be modulated. Gut signals inducing prophages
This paper analyses the policy changes occurring in the forest and palm oil sectors of Sabah, Malaysian Borneo, through the lens of the transformational change concept. The aim is to first examine whether Sabah is transforming and, if so, to identify the determinants enabling or hindering the change. To determine if Sabah is transforming, we used two criteria: - (i) an ambitious change in the policy framework, that promotes forest conservation and sustainable use, and is moving away from business-as-usual activities; and (ii) the level of implementation of the policies that we identified as supporting transformational change. We found that Sabah very likely did intend to transform. We made this conclusion based on comparing changes in policies occurring in Sabah, and we decided if it is ambitious by primarily comparing Sabah’s policies with other Malaysian states, the federal government, and internationally. We showed that: (i) Sabah decided to use voluntary international certification standards (private market instruments) like FSC and RSPO, while the other Malaysian states did not; (ii) they decided to protect more forest compared to national and international targets; and (iii) Sabah is an early mover as the state is one of the first in the world to adopt the RSPO Jurisdictional Approach. But intention needs to be followed by implementation, and this is where the state falls short. The policies in Sabah were not fully implemented because of the patronage system where the more powerful actors used their power to continue with business-as-usual activities, there is frequent political turnover in Sabah, and the state faced difficulty in meeting international standards. Our research shows that local leadership and a local transformational change coalition (civil society actively working in Sabah) mainly prompted the transformational change, although the promises of economic gains and better reputation also played a role. We conclude by emphasising the change must be made more compelling for political leaders, as part of a broader institutional structure, not only through the narrow focus on reducing deforestation but through the development of a more sustainable and equitable national economy, and that consumer countries should play a role in reducing pressures on forest by providing incentives to a state that manages its natural resources sustainably.
Allylation of phenols, a widely used reaction in multistep synthetic pathways, was herein investigated using mechanochemistry. This synthesis was first optimized on vanillin by varying key parameters including both chemical (e.g., stoichiometry, reaction time) and mechanical (e.g., rotational speed, material, size and number of beads, liquid additive) conditions, leading to the isolation of allylated vanillin at the gram scale in excellent yield (95%). The optimized procedure was also successfully implemented to another bio-based phenol of interest, ethyl ferulate (92% isolated yield). The environmental impact of these procedures was compared with more classical in-solution protocols by calculating E factors. When work-up solvents were not taken into account, E factor (sEF) clearly indicated superiority of the ball-milling approach over the solution-based procedure, underscoring the capacity of ball-mills to drastically reduce the need for “reaction” solvents. On the opposite, when work-up solvents were taken into consideration, E factors (cEF) were in favor of the solvent-based approach, which could be explained by the solvent quantities required to recover the reaction mixture from the ball-mill reactor. Overall, these results highlight i) the great potential of mechanochemistry to enable the development of both efficient and waste-less allylation of lignin-derived phenolic synthons and ii) the need to study higher-scale and continuous mechanochemical processes, such as by using extruders, to further improve efficiency and sustainability of such mechanochemical processes.
Context Recognized as a critical ecosystem service in farmland, pollination is threatened by the decline of pollinators, notably due the homogenization of the landscape and the decline of floral resources. However, there is still a limited understanding of the interplay between landscape features and the pulses of floral resources provided by mass-flowering crops. Objective The goals of this study were to (i) determine how pollination efficiency varies with the amount of floral resources at field and landscape scales through the oilseed rape (OSR) flowering period and (ii) quantify the magnitude of the pollination processes involved. Methods Pollination efficiency (fruiting success) was measured using OSR plant phytometers placed in grasslands, cereals and OSR fields varying in quantity of floral resources at both field and landscape scales. The individual contributions of different processes to pollination were determined using a bagging experiment on plant phytometers. Results Pollination efficiency was enhanced during both the temporal period and in landscapes with a high amount of OSR flowers, and semi-natural habitats as a result of higher pollinator presence. The bagging experiment also supported a complementarity between habitats for pollinators, as insect-pollination in grasslands and cereals was higher after OSR flowering, especially in OSR-rich landscapes, in regard to large-insect-pollination. Conclusions The floral resource availability drives insect-pollination through attraction, spillover, and spatial and temporal complementarities between habitats. These results suggest that maximizing pollination efficiency in farmland landscapes partly consisting of OSR fields should include a combination of habitats that provide continuous floral resources.
As decisions on climate change adaptation involve stakeholders with different values, beliefs and attitudes (VBA), decision outcomes depend on how stakeholders interact and how power is distributed. In this paper, we explore the VBA of stakeholders involved in three water management projects focusing on dams, micro-reservoirs, or wetlands in a Peruvian watershed facing droughts. We apply a framework with the core ideas of the hydrosocial cycle, the decision context perspective, and the VBA hierarchy to show how stakeholders’ perspectives and power influence practices on the ground. The analysis of VBA reveals three different perspectives on water management held by different stakeholder groups. First, a community-based perspective, frequent among local communities, favors micro-reservoirs managed by communities. Second, an infrastructure-based perspective, frequent among public sector stakeholders, shows a preference for dams managed by the private sector. Third, a nature-based perspective, with a preference for wetlands managed by the public sector, is found across stakeholder groups. In the three water management projects, different power distributions determine which VBA dominate and influence practices on the ground. Dams on the ground represent power from the public and private sectors, while micro-reservoirs represent local grassroot control. In the wetland project, the outcomes of the evolving hydrosocial cycle are still unclear and will depend on how multiple perspectives are considered. Examining and questioning the decision context in which adaptation occurs can help excluded stakeholders achieve more power and agency and tackle the fundamental question of ‘adaptation of what and for whom’.
Introduction L’insuffisance rénale chronique est une maladie fréquente dont la prévalence augmente, entraînant un coût important pour la société. Cependant un grand nombre de patient est adressé encore tardivement au néphrologue. Description L’objectif de cette étude était de déterminer à quel taux de DFG les médecins généralistes adressaient leurs patients insuffisants rénaux chroniques (IRC) au néphrologue et quels facteurs influençaient leur adressage. Méthodes Étude épidémiologique descriptive type étude de pratique par analyse des dossiers médicaux informatisés concernant les patients IRC stade 3B et moins des 11 médecins exerçant dans différents cabinets d’un pôle de santé. Résultats Les médecins généralistes ont adressé 32,81 % de leurs patients IRC stade 3B ou moins au néphrologue avec un taux de DFG moyen de 34,1 ml/min/1,73 m² à l’adressage. Ils adressaient davantage les patients avec une protéinurie positive (p = 0,002), ceux avec un taux de potassium élevé (p = 0,023), plus la perte annuelle du DFG était rapide (p = 0,003), moins la tension artérielle était équilibrée (p = 0,011) et plus les patients étaient autonomes (p = 0,004). Inversement, plus les patients étaient âgés, moins ils les adressaient (p < 0,001). Conclusion Cette étude est la première étude quantitative sur analyse de dossiers effectuée chez les médecins généralistes étudiant l’adressage au néphrologue. Effectuée chez les 11 médecins d’un pôle de santé exerçant dans différents cabinets avec une activité semi-rurale, elle reste monocentrique. L’effectif total est faible avec une certaine dépendance à l’égard de la tenue des dossiers. Les médecins généralistes ont une attitude curative plutôt que préventive pour le recours aux soins secondaires en néphrologie. L’offre en néphrologue étant insuffisante sur le territoire étudié, une aide complémentaire dans la prise en charge de ces patients via l’infirmière ASALEE pourrait être envisagée pour les médecins en difficulté.
Coastal lagoons are known to host numerous resident and migrant fish species. Spatio-temporal variation in abiotic and biotic conditions in these ecosystems results, however, in a mosaic of microhabitats that could differently affect juvenile growth and survival. To deepen our understanding of juvenile fish habitat requirements and their spatio-temporal use of lagoons, microhabitat characteristics and fish assemblages were monitored jointly in a small temperate lagoon (the Prévost lagoon), from March to October 2019. A total of 2206 juvenile fishes belonging to 22 species were collected. Resident lagoon species, especially Atherina boyeri, dominated the assemblage (74%), while, among migrant species, Sparus aurata (8%) and Liza aurata (5%) were the most represented. Changes in overall juvenile abundance were mainly temporal, following the seasonal shifts in water temperature, salinity, and chlorophyll a concentration (44.9% of the co-inertia). However, our results revealed that distinct types of microhabitats exist in small lagoons and that juvenile fish distribution among them is non-random. Indeed, fish species richness mainly differed among sampling sites in relation to their distance from the inlet and the complexity of the three-dimensional habitat structure (36.5% of the co-inertia). Juveniles preferentially selected microhabitats with medium to high structural complexity, which were essentially created by macroalgae. However, microhabitat preferences were both species and ontogenetic stage dependent, with more contrasting microhabitat requirements in young juveniles. These results underline the need for conservation measures to consider each lagoon as a dynamic mosaic of microhabitats with radically different importance for the juveniles of the various fish species that colonize them.
Wheat grain storage proteins, i.e. the gluten proteins, and alpha-amylase trypsin inhibitors are partially resistant to gastrointestinal digestion. They figure among the wheat components that are potential triggers of non-celiac wheat sensitivity. To explore the digestibility of bread wheat proteins in relation to heritable plant traits, old and modern wheat varieties grown in two environments were genotyped, phenotyped, and processed into breads, which were partially digested in vitro in a system resembling human digestion. The extent of proteolysis measured after 2 h of digestion was variable. Digestion of proteins present in bread made from old wheat cultivars registered before 1960 and modern cultivars registered after 1960 was similar. No major plant trait was correlated to partial protein digestibility of bread from cultivars with high grain protein content. The protein digestibility of bread from high yield cultivars was influenced by protein composition, as well as the genetic distance per chromosome from a reference variety. Improving high yield cultivars by breeding for highly digestible proteins might help to mitigate adverse reactions to a range of wheat proteins in susceptible individuals.
Maintenance practices in agricultural ditches influence their abiotic and biotic functioning in the short and medium term, leading to modifications of plant communities. These modifications might in turn affect the water transport regulation and seed retention functions of ditches. The effects of maintenance practices on ditch plant communities have been poorly studied in terms of (i) functional response traits to maintenance practices (ii) functional effect traits driving ecosystem functioning. We designed an experiment to compare the effects of different maintenance practices (mowing, burning, chemical weeding and dredging) in an agricultural Mediterranean ditch. We measured the plant species richness (i.e. alpha diversity or number of species), stem densities, and plant traits/community functional parameters affecting water transport and seed retention (height, blockage factor and surface vegetation ratio), every year during two years before and after applying contrasting maintenance practices. All the plants growing in the bottom and on the banks of the studied ditch were identified. We characterized the differences between treatments using linear mixed‐effects models. Maintenance practices differently affected plant communities and resulting ecosystem functions. After two years, burning was the poorest practice regarding seed retention and the best practice regarding hydraulic transport capacity, on the basis of a water‐depth of 60 cm in the ditch. Mowing was the poorest practice regarding water transport and was an averaged practice for seed retention. Mowing was also the practice favoring the highest richness. Chemical weeding did not really differ from the control in terms of studied traits and parameters, although a slight decrease in water conveyance ability and increase in seed retention was assessed after two years. The results pave the way to developing easy to implement maintenance solutions with the potential to optimize ecosystem functions, relying both on historical agricultural practices for farmers (involving no new know‐how) and on non‐introduced plant species.
Probiotics which are beneficial microorganisms for humans provide several health benefits including immunomodulation of the intestines and gut microbiota. In vitro safety assessment of the probiotic isolates that are used for human consumption needs to be performed which includes screening for hemolytic, gelatinase, DNAse activities, etc. We provide the method for determining DNAse activity by these candidate probiotics using in vitro studies.Key wordsProbioticsIn vitro safety assessmentDNaseDNase activity
Background Anthropogenic activities have increased the inputs of atmospheric reactive nitrogen (N) into terrestrial ecosystems, affecting soil carbon stability and microbial communities. Previous studies have primarily examined the effects of nitrogen deposition on microbial taxonomy, enzymatic activities, and functional processes. Here, we examined various functional traits of soil microbial communities and how these traits are interrelated in a Mediterranean-type grassland administrated with 14 years of 7 g m ⁻² year ⁻¹ of N amendment, based on estimated atmospheric N deposition in areas within California, USA, by the end of the twenty-first century. Results Soil microbial communities were significantly altered by N deposition. Consistent with higher aboveground plant biomass and litter, fast-growing bacteria, assessed by abundance-weighted average rRNA operon copy number, were favored in N deposited soils. The relative abundances of genes associated with labile carbon (C) degradation (e.g., amyA and cda ) were also increased. In contrast, the relative abundances of functional genes associated with the degradation of more recalcitrant C (e.g., mannanase and chitinase ) were either unchanged or decreased. Compared with the ambient control, N deposition significantly reduced network complexity, such as average degree and connectedness. The network for N deposited samples contained only genes associated with C degradation, suggesting that C degradation genes became more intensely connected under N deposition. Conclusions We propose a conceptual model to summarize the mechanisms of how changes in above- and belowground ecosystems by long-term N deposition collectively lead to more soil C accumulation.
It was time to take stock. We modified the humipedon classification key published in 2018 to make it easier and more practical. This morpho-functional taxonomy of the topsoil (humipedon) was only available in English; we also translated it into French and Italian. A standardized morpho-functional classification of humipedons (roughly the top 30–40 cm of soil: organic and organomineral surface horizons) would allow for a better understanding of the functioning of the soil ecosystem. This paper provides the founding principles of the classification of humipedon into humus systems and forms. With the recognition of a few diagnostic horizons, all humus systems can be determined. The humus forms that make up these humus systems are revealed by measuring the thicknesses of the diagnostic horizons. In the final part of the article, several figures represent the screenshots of a mobile phone or tablet application that allows for a fast recall of the diagnostic elements of the classification in the field. The article attempts to promote a standardized classification of humipedons for a global and shared management of soil at planet level.
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Jean-Pierre Chery
  • UMR TETIS (Territoires, Environnement, Télédétection et Information Spatiale)
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