25 research outputs found
Effects of two common fungicides on the reproduction of Aporrectodea caliginosa in natural soil
The use of pesticides in agroecosystems can have negative effects on earthworms, which play key roles in soil functioning such as organic matter decomposition. The aim of this study was to assess the effects of two fungicides (Cuprafor microÂź, composed of copper oxychloride, and Swing GoldÂź, composed of epoxiconazole (EPX) and dimoxystrobin (DMX)) on earthworm reproduction by exposing adults and cocoons. First, adult Aporrectodea caliginosa individuals were exposed for 28 days to 3.33, 10 and 30 times the recommended dose (RD) of Cuprafor microÂź corresponding to 25.8, 77.5 and 232.5âŻmgâŻkgâ1 dry soil of copper, respectively, and 0.33, 1 and 3 times the RD of Swing GoldÂź (corresponding to 5.2âŻĂâŻ10â2âŻmg DMX kgâ1 + 1.94 Ă 10â2âŻmg EPX kgâ1, 1.55âŻĂâŻ10â1âŻmg DMX kgâ1 + 5.81 Ă 10â2âŻmg EPX kgâ1 and 4.62âŻĂâŻ10â1âŻmg DMX kgâ1 + 1.74 Ă 10â1âŻmg EPX kgâ1 respectively), in addition to a control soil with no fungicide treatment. Cocoon variables (production, weight, hatching success, hatching time) were monitored. Second, ânaĂŻveâ cocoons produced by uncontaminated earthworms were exposed to soils contaminated by the same concentrations of the two fungicides, and we assessed hatching success and hatching time. In the first experiment, cocoon production was halved at the highest copper concentration (232.5âŻmg Cu kgâ1 of dry soil) as compared to the control. Cocoons took 5 more days to hatch, and the hatching success decreased by 35% as compared to the control. In the Swing GoldÂź treatments, cocoon production was reduced by 63% at 3 times the RD, and the hatching success significantly decreased by 16% at the RD. In the second experiment, only the hatching success of cocoons was impacted by Swing GoldÂź at 3 times the RD (30% less hatching). It is concluded that the cocoon stock in the soil is crucial for the renewal of populations in the field. The most sensitive endpoint was the hatching success of the cocoons produced by exposed adults. This endpoint and the effects observed on the ânaĂŻveâ cocoons could be taken into account in pesticide risk assessment
Indicateurs de biodiversitĂ© dans les exploitations agricoles biologiques et conventionnelles des VallĂ©es et Coteaux de Gascogne, cas dâĂ©tude français du projet europĂ©en BIOBIO
Dans le cadre du projet europĂ©en BIOBIO, nous avons comparĂ© entre pays les richesses en habitats et richesses spĂ©cifiques cumulĂ©es de quatre groupes taxonomiques (plantes, abeilles sauvages, araignĂ©es, vers de terre), de 169 exploitations biologiques ou conventionnelles appartenant Ă 10 pays. Pour le cas dâĂ©tude français, VallĂ©es et Coteaux de Gascogne, les corrĂ©lations entre indicateurs directs (richesses spĂ©cifiques des taxons et habitats) et indirects (pratiques agricoles) de biodiversitĂ©, relevĂ©s dans 8 exploitations conventionnelles et 8 biologiques, ont Ă©tĂ© recherchĂ©es. Les rĂ©sultats montrent que le nombre dâhabitats cultivĂ©s et surtout semi-naturels par exploitation est le principal facteur dĂ©terminant le niveau de biodiversitĂ© Ă cette Ă©chelle, pour le cas dâĂ©tude français comme pour les autres cas dâĂ©tude. Ce facteur explique en partie le plus haut niveau de biodiversitĂ© observĂ© pour le cas dâĂ©tude français. NĂ©anmoins, les pratiques, spĂ©cifiques ou non des modes de production biologique et conventionnelle, gouvernent gĂ©nĂ©ralement les paramĂštres de biodiversitĂ© Ă lâĂ©chelle de lâhabitat. In fine, le projet propose la mĂ©thode BIOBIO de suivi de la biodiversitĂ© dans les exploitations agricoles
Urban Climate, Human behavior & Energy consumption: from LCZ mapping to simulation and urban planning (the MapUCE project)
International audienceThe MApUCE project aims to integrate in urban policies and most relevant legal documents quantitative data from urban microclimate, climate and energy.The primary objective of this project is to obtain climate and energy quantitative data from numerical simulations, focusing on urban microclimate and building energy consumption in the residential and service sectors, which represents in France 41% of the final energy consumption. Both aspects are coupled as building energy consumption is highly meteorologically dependent (e.g. domestic heating, air-conditioning) and heat waste impact the Urban Heat Island. We propose to develop, using national databases, a generic and automated method for generating Local Climate Zones (LCZ) for all cities in France, including the urban architectural, geographical and sociological parameters necessary for energy and microclimate simulations.As will be presented, previous projects on adaptation of cities to climate change have shown that human behavior is a very potent level to address energy consumption reduction, as much as urban forms or architectural technologies. Therefore, in order to further refine the coupled urban climate and energy consumption calculations, we will develop within TEB (and its Building Energy Module) a model of energy consumer behavior.The second objective of the project is to propose a methodology to integrate quantitative data in urban policies. Lawyers analyze the potential levers in legal and planning documents. A few âbest casesâ are also studied, in order to evaluate their performances. Finally, based on urban planning agencies requirements, we will define vectors to include quantified energy-climate data to legal urban planning documents. These vectors have to be understandable by urban planners and contain the relevant information.To meet these challenges, the project is organized around strongly interdisciplinary partners in the following fields: law, urban climate, building energetics, architecture, sociology, geography and meteorology, as well as the national federation of urban planning agencies.In terms of results, the cross-analysis of input urban parameters and urban micro-climate-energy simulated data will be available on-line as standardized maps for each of the studied cities. The urban parameter production tool as well as the models will be available as open-source. LCZ and associated urban (and social!) indicators may be integrated within the WUDAPT database
Assessing landscape composition using visual assessment: accuracy of rapid description compared to digital mapping
International audienceWe compared the accuracy of visual assessment of landscape composition to that of Geographic Information Systems (GIS) mapping in (agro)ecology studies that focus on processes in which landscape factors are assumed to be insignificant and are often ignored. Seven land-use types were visually estimated from aerial photographs of contrasting rural landscapes in France. Visual assessment showed good agreement with results of GIS mapping for all land-use types, regardless of the observer. Estimates were accurate for forests and water areas, which are more visible than other land-use types. In contrast, observers often failed to distinguish crops from grassland, which decreased agreement for these land-use types; however, the estimate became fairly accurate when these land-use types were combined. Overall, this study confirms the relevance of using visual assessment to obtain simple landscape indices to improve studies that might otherwise ignore the landscape, provided that the loss of precision is compatible with the purpose of the study
Recommandations pour lâutilisation dâAporrectodea caliginosa s.s pour lâĂ©valuation du risque pesticide
Des bases de données urbaines aux simulations énergétiques - Le projet MApUCE
International audienceUrban energy is a domain that covers many complex processes thatinteract at all scales of the city: the microclimate (the heat island effect), building energy consumption for heating or cooling, inhabitantsâbehav-ior, renewable energyproduction, etc. Few tools take account ofthis level of complexity atthis scale, making the adaptation and mitigation to climate change very difficult to integrate into urban policies and design practices.Within the MApUCEresearch project, which proposes a methodology to carry out simulations of these urban energy processes across all towns and cities in France, we have developed an approach whose objective is to obtain accurate data onbuildingsâcharacteristics andmaterials. It is based on the implementationof an auto-matic method for determining the architectural and urban typologies for all cities of France and an architectural and historical database.The method for determining the typologiesis a comprehensive and automated methodto identify urban typolo-gies at the building and the city block scales. The method usesmorphologicalor sociodemographicindicators (determined from national databases)and makes a classification implementing a supervised learning method based on the "Random Forest".These typologies are coupled with the architectural databaseâs information, through the indication of the buildingsâusage, their date of construction and geographical location allowing to characterize each of the buildings in terms of materiality (albedo, constructive system thermal insulation, etc.), and HVAC systems.L'Ă©nergĂ©tique urbaine est un domaine qui couvre de nombreux pro-cessus complexes interagissant Ă toutes les Ă©chelles de la ville : le microclimat (l'effet d'Ăźlot de chaleur), la consommation Ă©nergĂ©tique des bĂątiments pour le chauffage ou la climatisation, les comportements Ă©nergĂ©tiques des habitants, la production d'Ă©nergie renouvelable, etc. Peu d'outils tiennent compte de ce ni-veau de complexitĂ© Ă cette Ă©chelle, rendant l'adaptation et l'attĂ©nuation aux changements climatiques trĂšs difficiles Ă intĂ©grer dans les politiques urbaines ou les pratiques de conception. Au sein du projet de recherche MApUCE, qui propose une mĂ©thodologie pour effectuer des simulations de ces processus d'Ă©nergĂ©tique urbaine Ă l'Ă©chelle de toutes les communes et villes de France, nous avons dĂ©veloppĂ© une approche dont l'objectif est de pouvoir obtenir des donnĂ©es prĂ©cises sur les caractĂ©ristiques et les matĂ©riaux des bĂątiments. Elle est basĂ©e sur la mise en oeuvre d'une mĂ©thode de dĂ©termination automatique des typologies architecturales et urbaines pour toutes les villes de France et d'une base de donnĂ©es architecturale et historique. La mĂ©thode de dĂ©termination des typologies est une mĂ©thode globale et automa-tisĂ©e, dĂ©rivĂ©e de GENIUS, pour identifier les typologies urbaines Ă l'Ă©chelle du bĂątiment et de l'Ăźlot urbain. Elle utilise des indicateurs morphologiques ou so-ciodĂ©mographiques (eux-mĂȘmes dĂ©terminĂ©s Ă partir des bases de donnĂ©es natio-nales) et rĂ©alise une classification mettant en oeuvre une mĂ©thode d'apprentissage supervisĂ© basĂ©e sur les « Random Forest ». Ces typologies sont croisĂ©es avec les informations de la base de donnĂ©es archi-tecturale, au travers de l'indication de l'usage des bĂątiments, leurs dates de construction et leur localisation gĂ©ographique permettant ainsi de caractĂ©riser chacun des bĂątiments en terme de matĂ©rialitĂ© (albĂ©do, systĂšme constructif, isolation thermique, etc.) et de systĂšmes CVC
A biology-based model to analyze growth data of earthworms exposed to copper at different development stages
Assessing effects of a contamination on populations require getting data on the whole life cycle and accounting for differences of sensitivity throughout this life cycle. Copper contamination is one of the greatest concerns in agricultural soils, especially in vineyards. This contamination may have negative effects on soil fauna, such as earthworms, which are recognized as ecosystem engineers providing very valuable ecosystemic services. To assess effects of copper on earthworm populations, we tested the impact of a commercial formulation of copper fungicide, i.e., Cuprafor MicroÂź (50% copper oxychloride), on different endpoints, including growth, for the earthworm species Aporrectodea caliginosa, one of the dominant earthworm species in agricultural fields. We performed original tests assessing the impact of copper on the growth at 3 different development stages with many times of measurements: new hatchling individuals (10-15 mg), small juveniles (90-110 mg) and large juveniles (260-340 mg). To analyze simultaneously all the data, we developed and used a biology-based model. This model is based on the DEB (Dynamic Energy Budgets) theory. A DEB model was set up and validated under controlled conditions, using different food conditions. The growth data were then analyzed with a toxicokinetics model (accounting for the influence of growth and differences between development stages) coupled with a DEB-based toxicodynamic model. Our results showed a drastic inhibition of growth once a No Effect Concentration, estimated at 65 mg kg-1 of copper for all stages, was exceeded. The time-profile of the effects was fully accounted for by the model. In conclusion, our model provided a relevant analysis of the toxicity data and provided understanding of the mechanisms of copper toxicity to earthworm growth, throughout development. The next step of our research will be to combine our biology-based model and reproduction data in a dynamic population model
A two-year field study to assess the effects of two fungicides and their mixture on oligochaete communities and the soil functioning
Agriculture intensification and in particular pesticide use can affect soil fauna and its affiliated ecological functions (e.g. organic matter decomposition). Adapted from the ISO standard method for earthworm field studies (ISO 11268-3, 2014), we tested the effects of two fungicides, i.e., Cuprafor MicroÂź and Swing GoldÂź - used respectively in organic and conventional agriculture - on oligochaetes (Lumbricidae and Enchytraeidae) and the soil functioning (i.e., feeding activity and organic matter decomposition with the bait lamina and tea bag methods, respectively). The trial consisted on four replicates of six experimental treatments (control, Cuprafor MicroÂź and Swing GoldÂź at x 1 and x 10 the recommended dose, and a mixture of both pesticides at the recommended dose, 1,5 l.ha-1 of Swing GoldÂź and 4 kg.ha-1 of copper) in a meadow located near the Palace of Versailles (France). After 1, 6, 12, and 18 months of experiment (i.e., t1, t6, t12, and t18), we compared the species composition of annelids and functional endpoints between treated and non-treated plots. A lower Shannon diversity index was found for earthworms in the treatment with the mixture of both pesticides at t1 and t6. However, no effect on earthworm abundance was observed in the mixture treatment mainly explained by the compensation of earthworm species. We also found a lethal effect of Swing GoldÂź on anecic earthworms at t1, while an effect of copper on annelids at ten times the recommended dose (40 kg.ha-1 of copper) was observed only after 12 months. These results could be explained by the various pesticide mechanisms on life history traits (i.e., growth, reproduction). However, we showed no overall significant difference in total feeding activity, enchytraeid density and diversity between treatments with or without pesticide at t1, t6, t12 and t18. In the Swing GoldÂź treatment, earthworm community did not fully recovered 18 months after pesticide application. This study underlines the need to study pesticide effects on non-target organisms as well as functional endpoints for more than one year after pesticide application. Another sampling campaign will be performed in spring 2018