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Major field margin vegetation types in France and their relationships with climate, agricultural landscapes and management intensity
No full textThe raw data are the property of the Ministry of Agriculture and are open to French public research on request. The consolidated data used for this article were produced by the GT STEP and the GTP. The raw data are the property of the Ministry of Agriculture and are open to French public research on request. The consolidated data used for this article were produced by the GT STEP and the GTP. They are available on request from the authors and under conditions, by signing a charter of use.International audienceArable field margins are an important semi-natural habitat providing multiple functions in agroecosystems. Despite three decades of research, analyses of species assemblage and functional traits are lacking. Leveraging a national monitoring network in metropolitan France, we aim to provide a comprehensive taxonomic and functional synthesis of field margin flora, outline main field margin types and explore their associations with management practices, climate, and agricultural landscapes. We analysed data from 532 field margins surveyed between 2013 and 2017, using both uni- and multivariate analyses. Field margins exhibited great diversity with 711 distinct taxa (12% of all flora in mainland France) at the national scale and an average of 16 species per 10 m2 locally. While field margins contained few species of conservation value, they offered a refuge for many declining species as well as rare arable weed species. We identified seven main field margin types, each linked to distinct conditions of climate, soil, landscape and agricultural practices. Mediterranean field margins notably differed from all others. In the main cluster, vineyard margins also stood out as distinct from annual crop margins. Additionally, field margins in landscapes with a high proportion of grassland differed from those within intensively cultivated field crop plains in conventional agriculture. Overall, our study highlights the high botanical diversity of field margins and their interest for plant conservation in agricultural landscapes. Promoting the installation and/or maintenance of field margins through agri-environmental schemes should thus favour biodiversity conservation and associated ecosystem provision
Mediterranean vineyard soil seed bank characterization along a slope/disturbance gradient: Opportunities for land sharing
No full textInternational audienceThe Mediterranean region is predicted to experience more intense rainfall events separated by severe droughts due to climate change. In agrosystems, the intensification of rainfall on dry bare soils will lead to an increase in runoff and erosion rates, especially on slopes. A common method to reduce erosion is to cover the soil with vegetation. To save costs, this vegetation could be provided by the soil seed bank. Vineyards situated on slopes are part of the typical Mediterranean landscape; thus, developing vegetation cover inside vineyards could be a solution to fight growing erosion risks in addition to providing other valuable services. However, the relationship between slope, erosion and seed loss can vary. Another key ingredient in the development of spontaneous vegetation cover is the spatial dispersal of seeds from one place to another, but the amount of seeds displaced depends on their respective dispersal modes. In this study, we sampled the soil seed bank at two sites characterized by either a low or high frequency of vegetation removal. The soil seed bank was sampled along a transect starting upslope of the vineyards to the bottom of neighboring agricultural ditches. Germination trials were carried out to define the soil seed bank in terms of species and seed density. Each identified species was linked with a main dispersal mode. Our main objective was to assess the effect of vegetation cover on seed loss inside a vineyard, as well as the potential differences in the soil seed bank along our transect and the influence of dispersal mode on those differences. Despite previous contradictory literature, vegetation did not seem to protect interrows from seed loss caused by runoff. Overall, our results support the use of the soil seed bank to provide spontaneous vegetation cover to limit present and future erosion rates and advocate for relaxing vegetation removal operations
Transforming weed management in sustainable agriculture with artificial intelligence: a systematic literature review towards weed identification and deep learning
No full textInternational audienceHighlights: • AI in weed management potentials for transforming agricultural ecosystems. • AI influence in economic, social, technological, and environmental dimensions. • AI's role in enhancing food safety by reducing pesticides residues. • Digital literacy as a crucial enabler empowering stakeholders to use AI effectively.Abstract: In the face of increasing agricultural demands and environmental concerns, the effective management of weeds presents a pressing challenge in modern agriculture. Weeds not only compete with crops for resources but also pose threats to food safety and agricultural sustainability through the indiscriminate use of herbicides, which can lead to environmental contamination and herbicide-resistant weed populations. Artificial Intelligence (AI) has ushered in a paradigm shift in agriculture, particularly in the domain of weed management. AI's utilization in this domain extends beyond mere innovation, offering precise and eco-friendly solutions for the identification and control of weeds, thereby addressing critical agricultural challenges. This article aims to examine the application of AI in weed management in the context of weed detection and the increasing impact of deep learning techniques in the agricultural sector. Through an assessment of research articles, this study identifies critical factors influencing the adoption and implementation of AI in weed management. These criteria encompass factors of AI adoption (food safety, increased effectiveness, and eco-friendliness through herbicides reduction), AI implementation factors (capture technology, training datasets, AI models, and outcomes and accuracy), ancillary technologies (IoT, UAV, field robots, and herbicides), and the related impact of AI methods adoption (economic, social, technological, and environmental). Of the 5821 documents found, 99 full-text articles were assessed, and 68 were included in this study. The review highlights AI's role in enhancing food safety by reducing herbicide residues, increasing effectiveness in weed control strategies, and promoting eco-friendliness through judicious herbicide use. It underscores the importance of capture technology, training datasets, AI models, and accuracy metrics in AI implementation, emphasizing their synergy in revolutionizing weed management practices. Ancillary technologies, such as IoT, UAVs, field robots, and AI-enhanced herbicides, complement AI's capabilities, offering holistic and data-driven approaches to weed control. Additionally, the adoption of AI methods influences economic, social, technological, and environmental dimensions of agriculture. Last but not least, digital literacy emerges as a crucial enabler, empowering stakeholders to navigate AI technologies effectively and contribute to the sustainable transformation of weed management practices in agriculture
Effect of the water content and the lengthening of fatty acids chain on the iCALB ‐catalyzed esterification in deep eutectic solvents
No full textInternational audienceFour Deep Eutectic Solvents (DES) based on choline chloride (ChCl) and different hydrogen bond donors (1,4‐butanediol, glycerol, isosorbide, and urea) were tested as reaction medium for the immobilized Candida antarctica B (iCALB) lipase‐catalyzed esterification of fatty acids with n‐butanol. Although the strong hydrogen bonds between DES components were expected to lower their reactivity, all except urea, competed in the esterification reaction. To study the effect of acyl group donor and water, different chain length of saturated fatty acids (ranging from 6:0 to 18:0) and water content (ranging from 0, 1, 2 or 3 molar ratio of water/ChCl) were tested in the lipase‐catalyzed esterification with n‐butanol in ChCl:urea (1:2, molar ratio). When the incubation was performed in the absence of water, the shorter the fatty acid chain length, the higher the conversion. Upon water addition, a drastic increase in the esterification rate of all the fatty acids was observed and, conversely to what occurred in the anhydrous media, the longer the fatty acid chain length, the higher the conversion. Results suggest that water concentration in the DES medium possesses a multifactorial effect, as it influences the enzyme activity, the solvent viscosity, the DES structure, and the interaction between DES components, substrates, and enzymes, thus determining the efficiency and yield of the esterification reaction
LoggingLab: An R package to simulate reduced-impact selective logging in tropical forests using forest inventory data
No full textInternational audienceEven where Reduced-Impact Logging (RIL) practices are applied, selective logging causes substantial damage to tropical forests. To further reduce selective logging damage, the practices that cause the most damage need to be identified and alternatives tested. To this end, we developed the R package LoggingLab, a spatially-explicit and individual tree-based selective logging simulator and demonstrated its functions using data from French Guiana. LoggingLab explicitly simulates damage during each stage of the selective logging process taking into account topography and hydrography, which are main constraints on logging. Most LoggingLab parameters can be easily adjusted to a wide range of local contexts. LoggingLab can also be coupled with forest dynamics models to simulate the long- term effects of different selective logging scenarios
Do farmers participating in short food supply chains use less pesticides? Evidence from France
No full textInternational audienceProponents of short food supply chains (SFSC) have lauded their environmental benefits. Nevertheless, most studies on SFSCs have focused on their climate impact, while the synthetic pesticide use by farmers participating in SFSCs has received little research attention. In this study, we investigate the effect of farmers' involvement in different SFSC channels on synthetic pesticide use and crop yields. This study relies on data obtained from the 2020 French agricultural census and a 2018 French national survey on the phytosanitary practices of representative market gardeners. This paper uses a multinomial endogenous treatment effect model in order to account for endogeneity. We demonstrate that the effect of SFSC participation on farmers' synthetic pesticide use varies depending on the type of SFSC channel employed. Farmers who sell part of their vegetable crops through direct-to-consumer (DTC) channels use significantly fewer synthetic pesticides than those who only sell their crops through long food supply chains (LFSC). However, there is no evidence that farmers involved in direct-to-retailer (DTR) channels use significantly fewer synthetic pesticides. In addition, we have not found any evidence that SFSC participation decreases crop yields
Effect of crop management and climatic factors on weed control in sugarcane intercropping systems
No full textInternational audienceContext: Cover crops in intercropping systems have a high potential to manage weeds in tropical agroecosystems as an herbicide alternative. However, it still needs to be better investigated in sugarcane cropping systems. Objective: This study assesses the weed control ability of cover crops in sugarcane intercropping systems depending on crop management and climate in tropical conditions. Methods: This study was based on a set of eight experiments, including ten cover crop species, performed from 2012 to 2021 in three areas in Reunion Island (France) and comparing three inter-row management treatments: i) chemical weed control, ii) cover crops sown in the inter-row, and iii) low weed control. Mean weed and cover crop ground cover were measured during the entire crop cycle, and the complementary weed management practices (herbicide, manual weeding) were also recorded. Sugarcane yield and crop management were evaluated to assess the economic impact of a change in practice. Results: Mean weed ground cover was reduced by 51 % in the cover crop and chemical treatments compared to low control. Additionally, the cover crop treatment had an herbicide treatment frequency index lower by 37 % compared to chemical treatment but a higher number of manual weedings. In all treatments, weed cover increased with rainfall and temperature. In the cover crop treatment, a structural equation modeling approach allowed us to highlight the influence of cover crop (sowing date and species) and sugarcane management (crop cycle - plant or ratoon crop) on weed cover. Weed cover decreased with an increase in cover crop ground cover, which was higher for the early sowing date. Additionally, weed cover was lower in ratoon crops than plant crops but increased over time since intercropping was implemented. Finally, sugarcane yield was lower by 6 % in cover crop treatment compared to chemical treatment. The change in operating costs and revenues between these crop management induced a decrease in profits in intercropping compared to chemical cropping systems, variable according to the degree of mechanization. Conclusions: This study highlights the predominance of management factors, compared with climate, to explain the effectiveness of weed control in sugarcane intercropping systems. Implications: Due to the change in weed cover over time, there is a need to assess the long-term sustainability of this practice and the potential change in weed communities
Reconstructing Vineyard Geography, Yields and The Profitability of Wine Production in The Roman Empire: New Insights from Spatial Analysis, and Agent-Based and Climate-Vegetation Modelling
No full textInternational audienceBringing together a wide array of modern scientific techniques and interdisciplinary approaches, this book provides an accessible guide to the methods that form the current bedrock of research into Roman, and more broadly ancient, wine. Chapters are arranged into thematic sections, covering biomolecular archaeology and chemical analysis, archaeobotany and palynology, vineyard and landscape archaeology and computational and experimental archaeology. These include discussions of some of the most recent techniques, such as ancient DNA and organic residue analyses, geophysical prospection, multispectral imaging and spatial and climatic modelling. While most of the content is of direct relevance to the Roman Mediterranean, the assortment of detailed case studies, methodological outlines and broader ‘state of the field’ reflections is of equal use to researchers working across disparate disciplines, geographies, and chronologies. The study of ancient Roman wine has been dominated until recently by traditional archaeological analyses focused upon production facilities and ceramic evidence related to transport. While such architecture and artefact-focussed approaches provide a fundamental foundation for our understanding of this topic, they fail to provide the requisite nuance to answer other questions regarding grape cultivation and wine production, consumption, use and trade. As the first compendium of its kind, this book supports the embedding of modern scientific and experimental techniques into archaeological fieldwork, research and laboratory analysis, pushing the boundaries of what questions can be explored, and serving as a launching point for future avenues of interdisciplinary research. This volume presents an array of cutting-edge scientific and archaeological methodologies used in the study of vine-growing and winemaking in the Graeco-Roman Mediterranean. Recent work on this subject tends to be dominated by traditional archaeological analyses of press facilities and, above all, ceramic evidence. These approaches lack the nuance to answer several vital questions about Greek and Roman grapevine cultivation and wine production, consumption, use and trade. In response, modern scientific techniques are increasingly filling these gaps in both fieldwork and laboratory contexts. By bringing together a wide range of disciplinary approaches in one location, this book provides an accessible guide to the scientific methodologies that form the new bedrock of current research on ancient wine. Arranged into thematic sections covering biomolecular archaeology and chemical analysis, archaeobotany and palynology, vineyard and landscape archaeology, and computational modelling and experimental archaeology, its detailed exemplary case studies and ‘state of the field’ chapters can be immediately utilized by researchers working across disparate fields, chronologies and research contexts as reliable points of reference. As the first compendium of its kind, it aims to foster interconnection of modern scientific technologies with archaeological fieldwork and analysis, pushing the boundaries of what questions can be explored and serving as a foundation for future avenues of research into ancient wine production
Beyond variance: simple random distributions are not a good proxy for intraspecific variability in systems with environmental structure
No full textThe role of intraspecific variability (IV) in shaping community dynamics and species coexistence has been intensively discussed over the past decade and modelling studies have played an important role in that respect. However, these studies often implicitly assume that IV can be represented by independent random draws around species-specific mean parameters. This major assumption has largely remained undiscussed, although a great part of observed IV is structured in space or time, in particular when environmental dimensions that influence individual performance are imperfectly characterised or unobserved in the field. To test the impact of this strong assumption on the outcome of community dynamics models, we designed a simulation experiment where we varied the level of knowledge of the environment in virtual communities, resulting in different relative importance of explained vs unexplained spatial individual variation in performance. We used a community dynamics simulator to generate communities where the unexplained individual variation is, or is not, added as an unstructured random noise. Communities simulated with unstructured IV never reached the community diversity and composition of those where all the variation was explained and structured (perfect knowledge model). This highlights that incorporating unstructured IV (i.e. a random noise) to account for unexplained (but structured) variation can lead to incorrect simulations of community dynamics. In addition, the effects of unstructured IV on community diversity and composition depended on the relative importance of structured vs unstructured IV, i.e. on the level of knowledge of the environment, which may partly explain the contrasting results of previous studies on the effect of IV on species coexistence. In particular, the effect of unstructured IV on community diversity was positive when the proportion of structured IV vs unstructured IV in the model was low, but negative when this proportion was high. This is because unstructured random noise can either limit the competitive exclusion of inferior competitors in low dimensions or destabilise tight niche partitioning in high dimension. Our study suggests that it is crucial to account for the sources and structure of observed IV in real communities to better understand its effect on community assembly and properly include it in community dynamics models
Responses of the hyper‐diverse community of canopy‐dwelling Hymenoptera to oak decline
No full textThe data that support the findings of this study are openly available in Recherche Data Gouv at https://entrepot.recherche.data.gouv.fr/dataset.xhtml?persistentId=doi:10.57745/H8CBG1. Representative specimens of Braconidae, Ichneumonidae, Halictidae, Andrenidae, Crabronidae and Pemphredonidae are housed at the Orléans Museum for Biodiversity and Environment (MOBE, Orléans, France).International audience1. Forest decline and dieback are growing phenomena worldwide, resulting in severe, large-scale degradation of the canopy. This can profoundly alter the provision of trophic resources and microhabitats for canopy-dwelling arthropods.2. In 2019, we assessed the effect of oak decline on the community of canopy-dwelling Hymenoptera. We selected 21 oak stands and 42 plots, located in three forests in France, presenting contrasting levels of decline. Insects were sampled at the canopy level with green multi-funnel and flight-interception traps.3. We collected a particularly diverse community of 19,289 insect individuals belonging to 918 taxa, 10 larval trophic guilds and 7 nesting guilds.4. Oak decline had no effect on the abundance or richness of the overall community but significantly reshaped the community assemblages. Decline had contrasting effects depending on the taxa and guilds considered. Specialist parasitoids were more abundant at intermediate levels of decline severity while generalists were negatively affected. Taxa depending on ground-related resources and microhabitats were promoted. Saproxylic taxa were more abundant while xylophagous insects were negatively impacted.5. Reduced leaf area index promoted several guilds and the diversity of the overall community. While an increasing tree mortality rate enhanced the abundance and diversity of deadwood resources, it had negative impacts on several Hymenoptera guilds. Our results suggest that micro-environmental changes at the ground level due to canopy decline have major cascading effects on the communities of canopy-dwelling Hymenoptera.6. Our study highlights the relevance of studying Hymenoptera communities to investigate the outcomes of disturbances on forest biodiversity