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Clustering of Exogenous Organic Material Properties to Improve Their Efficient Recycling in European Agriculture
No full textInternational audienceExogenous organic materials (EOMs) are increasingly used as substitutes for mineral fertilizers and as tools to restore soil health within a circular bioeconomy context. However, the great diversity of EOMs in terms of origin, composition, chemical properties, and contaminant concentrations challenges their safe and efficient use in agriculture. The aim of the study was to establish a framework for the clustering of EOMs properties from several EU countries, enabling their categorisation according to their origin, characteristics, and chemical properties and trace elements (TE) profile. For that purpose, a dataset with chemical characteristics and TE concentrations from 118 EOMs was constructed from a database previously published. The EOMs included a wide range of organic residues and waste streams from agricultural, industrial, and urban origins representative of the diversity of European EOMs. Clustering analyses were carried out to distribute EOMs among clusters (i) of chemical properties based on their characteristics (dry mass, C‐to‐N ratio, pH, and concentrations of organic C, N, NNH 4 , P, K, Ca, and Mg), and (ii) of TE profile based on their concentrations of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn. Five practical scenarios of EOMs applications mixing amending and fertilizing EOMs were considered to estimate input fluxes of C, N, P, K, and TEs over a period of 10 years in contrasted areas (agricultural settings and peri‐urban areas). The present study clustered the EOMs according to their soil improver characteristics that is, from NK fertilizing to liming and organic amending properties. The clustering analysis on TEs classified EOMs according to their TE profiles, with (i) smaller concentration of TEs (i.e., three quarters of EOMs), and (ii) larger concentration of all TEs and especially for Cu and Zn. The various practical scenarios simulating the repeated applications of local EOMs from contrasted areas showed that input fluxes were in line with commercial organic fertilizer inputs and below the goal of 170 kg N per hectare per year, while TE input fluxes respected the French regulation thresholds, even in the scenarios including EOMs containing also greater TE levels
Do neighboring countries matter when explaining bilateral remittances?
No full textNational audienceWe measure to what extent neighboring countries affect the amount of remittances between a source and a recipient country, controlling for the commonly used macro determinants of remittances(such as, economic activity, inflation, distance and transaction costs). For the study, we rely on bi-lateral remittances’ data involving 67 source countries and 129 recipient countries all over the word. We provide novel evidence on the importance of neighbouring countries on remittance flows, with the parameter estimates capturing origin- and destination-spatial dependence being both positive and significant. This result is crucial, because disregarding the role of neighbouring countries leads to biased estimates for the determinants of remittances and misprediction. Indeed, prediction errors decrease by 67% when we correctly account for the role of neighbouring countries (relative to the standard non-spatial model for bilateral remittances). By properly accounting for the role of neighboring countries, we then re-examine the altruism and investment motives to remit. Finally, we apply our model estimates to quantify the expected negative impact of the COVID pandemic shock on the bilateral remittances. Interestingly, we find that remittances may be more resilient for low-and middle-income countries, which are the ones that rely on remittances the most
Mid-Term Lessons Learned from a Voluntary Carbon Footprint Reduction initiative in a Climate Lab Aiming for a 50% Reduction in 10 Years
No full textFive years ago, in 2020, 250 staff of a research laboratory in Grenoble, France signed a commitment to reduce their laboratory's greenhouse gas (GHG) emissions by 50% from 2019 to 2030, while continuing to carry out research on climate, the water cycle, glaciers, oceans and environmental pollution. This paper reports the mid-term (i.e. five years) impact of this reduction strategy on the research practices. It describes how the strategy was developed and adopted, and what was the subsequent trajectory on business travel, commuting, purchasing, energy consumption and computing. After five years of experimentation, the laboratory has reduced its overall carbon footprint by 35%, with a greater reduction in travel (-49% on business travel, -42% on commutes) than in purchases, which remained stable over the period. Notable changes in travel destinations have been observed, as well as a clear increase in very long train journeys (> 2000 km round trip), rising from 1% in 2018 to 13% in 2024. The strategy also motivated a major internal financial effort to replace the existing cold rooms refrigeration system that uses gases with a high global warming potential. A midterm survey (carried out in early 2025) indicate that the staff's perception of the overall trajectory (2020-2030) is largely positive and indicate a favourable agreement to the approach. Indeed, from past trajectory 74% of the respondents thought that the reduction had no (or very little) negative impact on the way they do research; and concerning future 98% of staff respondent wanted to continue with the current trajectory (-6%/year of GHG emission)
Plant-wax n-alkanes from the central Congo Basin as palaeo-environmental and -climatic proxies
No full textInternational audienceThe central Congo Basin is home to the world's largest tropical peatland complex and is covered with swamp forest. In the face of climate change and future human activities in the region, it is important to understand the factors that determine the nature and dynamics of the peatland vegetation cover. One way to gain insight into these factors is to reconstruct the history of the central Congo Basin peatlands. Analysing lipid biomarkers extracted from peat cores such as plant wax n-alkanes enables past environmental and climatic conditions to be reconstructed. However, there is currently no information on how the production of plant waxes by different plant species influences the abundance and isotopic composition of n-alkanes in peat and other archives in the Congo Basin. In this study we analysed plant wax n-alkane abundances, delta C-13 and delta D values according to photosynthetic pathways (C-3 vs. C-4), angiosperm subclasses (dicotyledons vs. monocotyledons), and source water delta D values in the dominant plant types (trees, shrubs, and herbs) in the peatland area of the Cuvette Department in the Republic of the Congo. Our dataset enables the definition of a new n-alkane distribution index, named GRIND, that distinguishes between C-3 (mostly dicotyledons) and C-4 (monocotyledons) plants as follows: (n-C-27 + n-C-33 + n-C-35)/(n-C-25 + n-C-27 + n-C-29 + n-C-31 + n-C-33 + n-C-35). This index may therefore be used to analyse Central African peat deposits and derive the relative abundance of C-3 and C-4 plant waxes in the past, independently of delta C-13 measurements. Furthermore, delta C-13 values from the central Congo Basin and other African sites suggest that environments with high relative humidity (> 80%) are characterised by very negative delta C-13 values (i.e., < -37 parts per thousand) of n-C-29 and n-C-31 alkanes. This observation highlights the potential of n-alkane delta C-13 in deriving climatic information under high relative humidity conditions in Central African lowlands, and contribute to palaeo-climatic reconstructions. Finally, the delta D values of n-C-29 and n-C-31 alkanes demonstrate that, despite contrasting apparent fractionation values associated with photosynthetic pathways and plant functional types - which can be accounted for using delta C-13 and pollen data in sedimentary deposits - they reliably reflect the delta D of environmental water. This confirms that plant wax n-alkane delta D values are effective tools for reconstructing palaeo-climatic changes in equatorial regions
Estimation of milk yield and lambs’ growth during the suckling period for the Sicilo-Sarde breed in Tunisia
No full textInternational audienc
Comparative seed physiological ecology in Coffea species highlights variation in germination strategies associated with climate and phylogeny
No full textSource Agritrop Cirad (https://agritrop.cirad.fr/617001/)International audienceBackground and Aims Seed functional traits are poorly understood in species of tropical origin with endospermic or desiccation-sensitive seeds. Species of the genus Coffea have colonized a broad range of forest habitats of Africa and Indian Ocean islands, from seasonally dry savannah woodlands to permanently humid evergreen forests. All Coffea species produce albuminous seeds, most of which are desiccation-sensitive, thereby offering a valuable model to identify adaptive seed traits in this understudied category of plants. Methods Several morphological traits (tissue masses and mass ratios, embryo depth inside the endosperm) and physiological traits (desiccation tolerance, germination and seedling establishment kinetics) were measured in 28 Coffea species, and associations with bioclimatic variables and phylogeny were investigated. Key Results The time required for seed germination was influenced by both the thickness of the micropylar endosperm and the relative mass of the endocarp to the seed. The time from germination to the unfolding of cotyledonary leaves was correlated with the endosperm mass. Finally, the time for seedling establishment, seed germination and drying sensitivity were positively associated with rain variables, suggesting that these physiological traits were driven by adaptation to seasonal water stress. Significant phylogenetic signal was detected for most seed traits with the exception of seed desiccation sensitivity, germination time and embryo depth inside the endosperm, which appeared to be evolutionarily labile, i.e. highly divergent between phylogenetically closely related species that occur in contrasted habitats. Conclusions The present study highlights the spectrum of coordinated seed traits shaped by phylogeny and/or ecological adaptation among Coffea species. This is illustrated by the co-option of several characteristics (small, thinly endocarp-coated, desiccation-tolerant and fast-germinating seeds) that enable fast seedling establishment and may confer an ecological advantage in the studied species of the East Africa clade that occur in seasonally dry habitats
Wine must yields as indicators of May to July climate in Central Europe, 1416–1988
No full textInternational audienceThe paper explores to which extent narrative documentary records on wine production in Central Europe can be used as a proxy for summer temperatures. Here, we compiled 11 regional series spanning from the early 15th century to 1988. We detrended the data to adjust for long-term biases such as warfare-related population decline. The homogenised regional series were subsequently merged into three supra-regional series: (1) the Mosel series, starting in 1416 and consisting of data from the former city-republic of Metz (France) and the Grand Duchy of Luxembourg; (2) the series for Germany, starting in 1511 and mainly originating from the former city-state of Heilbronn; and (3) the third series, starting in 1529 and representing production on the Swiss Plateau. The residuals of the supra-regional yield series were averaged, divided into seven classes, and multiplied by five quality classes. Yield quality indices (YQI) varying between 35 (large and excellent) and 1 (small and undrinkable) significantly correlated with temperatures between May and July. Regression analysis of the composite series revealed that yield and quality primarily depend on the climate conditions from May to July as well as on those in June of the previous year. Crops with a YQI > 28 (rated “good” by traditional winegrowers) were related to above-average May–July temperatures, early grape harvest dates and high tree-ring maximum latewood density values resulting from frequent anticyclonic weather situations. Crops with YQI > 10 could not be uncritically assigned to cold summers since severe winter conditions, and spring frosts sometimes substantially reduced yields without affecting quality, particularly during the Little Ice Age in the marginal Mosel and German areas. Extreme yield fluctuations challenged winegrowing communities. Overproduction induced wastefulness, while crop failures sometimes triggered witch hunts
Prognostic Value of Combining Serum Tryptase and Bone Mineral Density in Predicting Fractures in Systemic Mastocytosis
No full textInternational audienceNo abstract availabl
Adoption des programmes d'agriculture carbone : les risques comptent
No full textInternational audienceEnsuring that carbon farming credits accurately reflect actual carbon sequestration is a major challenge. Although activity-based schemes are the most common design in voluntary carbon farming schemes, the economic literature has shown that result-based schemes are more cost-effective. However, the risk induced by result-based schemes when carbon sequestration is not known with certainty ex ante is often overlooked. We propose a stylized economic framework that integrates soil science data and models to investigate how carbon accrual uncertainty affects farmers' adoption of carbon farming schemes. This framework is illustrated with a data set combining observations from a long-term experimental site (Ultuna, Sweden), multi-model ensemble simulations of soil organic carbon dynamics, and a wide range of economic assumptions. We investigate both analytically and quantitatively the conditions under which a farmer chooses to participate in a voluntary carbon farming scheme when the quantity of carbon eventually stored is uncertain. Various carbon are explored, farming schemes differing inmonitoring costs and accuracy, with contrasting risk implications for the farmer. In particular, hybrid schemes that are based on the expected SOC accrual, but include an uncertainty discount are examined. It is shown that the incentives to participate in a result-based scheme may decrease with increasing carbon prices, and that hybrid schemes may foster adoption by farmers.Veiller à ce que les crédits de carbone agricole reflètent fidèlement la séquestration réelle du carbone représente un défi majeur. Bien que les programmes basés sur les activités soient les plus courants dans les programmes volontaires de carbone agricole, la littérature économique a montré que les programmes basés sur les résultats sont plus rentables. Cependant, le risque induit par les programmes basés sur les résultats lorsque la séquestration du carbone n'est pas connue avec certitude ex ante est souvent négligé. Nous proposons un cadre économique stylisé qui intègre des données et des modèles de science du sol afin d'étudier comment l'incertitude liée à l'accumulation de carbone affecte l'adoption des programmes de culture carbone par les agriculteurs. Ce cadre est illustré à l'aide d'un ensemble de données combinant des observations provenant d'un site expérimental à long terme (Ultuna, Suède), des simulations multi-modèles de la dynamique du carbone organique du sol et un large éventail d'hypothèses économiques. Nous étudions de manière analytique et quantitative les conditions dans lesquelles un agriculteur choisit de participer à un programme volontaire de culture carbone lorsque la quantité de carbone finalement stockée est incertaine. Divers programmes de carbone sont explorés, avec des coûts de surveillance et des niveaux de précision variables, et des implications contrastées en termes de risque pour l'agriculteur. En particulier, les programmes hybrides basés sur l'accumulation prévue de carbone organique dans le sol, mais incluant une décote pour incertitude, sont examinés. Il est démontré que les incitations à participer à un programme basé sur les résultats peuvent diminuer avec l'augmentation des prix du carbone, et que les programmes hybrides peuvent favoriser l'adoption par les agriculteur
La distribution des champignons mycorhiziens sur les écorces d'arbres corrèle avec la préférence d'hôte de l'orchidée épiphyte tropicale Bulbophyllum variegatum sur l'île de La Réunion
No full textInternational audienceWhile host preference of tropical epiphytic plants is mainly driven by tree abundance and size, the distribution of mycorrhizal fungi among tree species is likely to influence host preference in orchids. Here, we investigated the host preference of ten epiphytic orchids in a one-hectare forest plot in La Réunion, revealing a strong preference in the orchid Bulbophyllum varigatum.Using an Illumina sequencing of the ITS-2 barcode of fungi, we identified fungal communities, including mycorrhizal Tulasnellaceae, both in the bark of host tree species in the area and in the roots of B. variegatum across the island. Bark-dwelling fungal and mycorrhizal communities varied between tree species, with fungal OTUs being specific to the host of B. variegatum. Three of them (one Serendipitaceae and two Tulasnellaceae) were found to be mycorrhizal at different stages of the orchid's life cycle. Our results suggest that the uneven distribution of mycorrhizal fungi between tree barks could influence the host preference of epiphytic orchids, a hypothesis that will require experimental testing.Alors que la préférence d'hôte des plantes épiphytes tropicales dépend principalement de l'abondance et de la taille des arbres, la répartition des champignons mycorhiziens sur les différentes espèces d'arbres est susceptible d'influencer celle des orchidées . Dans cette étude, nous avons étudié la préférence d'hôte de dix orchidées épiphytes dans une parcelle forestière d'un hectare à La Réunion, révélant une forte préférence d'hôte chez l'orchidée Bulbophyllum varigatum. À l'aide d'un séquençage Illumina du code-barre fongique ITS-2, nous avons identifié les communautés fongiques, notamment les Tulasnellaceae mycorhiziens, à la fois dans l'écorce des espèces d'arbres hôtes de la région et dans les racines de B. variegatum à travers l'île. Les communautés fongiques et mycorhiziennes vivant dans l'écorce varient selon les espèces d'arbres, certaines OTUs fongiques étant spécifiques à l'hôte B. variegatum. Trois d'entre elles (un Serendipitaceae et deux Tulasnellaceae) se sont avérées mycorhiziennes à différents stades du cycle de vie de l'orchidée. Nos résultats suggèrent que la répartition inégale des champignons mycorhiziens entre les écorces des arbres pourrait influencer la préférence d'hôte des orchidées épiphytes, une hypothèse qui devra être vérifiée expérimentalement