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The rhizosphere is essential for crop growth and yields and can be affected by factors such as agricultural practices or fertilizers. The effect of the type of organic manure on the density of mycorrhizal spores in the tomato rhizosphere and on the agronomic parameters was evaluated in the Saguiya area. The experimental design comprised 48 plots treated with three types of organic manure (cow dung, goat dung and poultry manure) at three levels of fertilization (100%, 125% and 150%) with four replicates, during a campaign of three months. The exotic tomato variety Tropimech was grown with monitoring of agronomic parameters, and soil samples were taken for the extraction and counting of arbuscular mycorrhiza fungi spores. Treatment T3 of test 3 (i.e., 150% poultry manure plus organic matter) was the most effective, producing 38 t ha-1 for fruit yield, 13 t ha-1 yield for leaf part and 6 t ha-1 for the root part. The main genera of CMA spores found are Glomus sp, Gigaspora sp and Scutellospora sp. The density of Scutelospora sp was the highest also for the poultry manure treatment and a strong positive correlation was found between spore density and agronomic parameters. The results show that organic amendments, in particular poultry manure, improve fertility and the density of AMF spores in the soils of this region., La rhizosphère est très importante pour la croissance et les rendements des cultures et peut être affectée par des facteurs comme les pratiques agricoles ou les fertilisants. L’effet du type de fumure organique sur la densité des spores mycorhizogènes dans la rhizosphère de la tomate et sur les paramètres agronomiques a été évalué dans la zone de Saguiya (Niger). Le dispositif expérimental mis en œuvre comporte 48 parcelles traitées avec trois types de fumure organique (bouse de vache, bouse de chèvre et fumure de volaille) à trois niveaux de fertilisation (100%, 125% et 150%) en quatre replicats, pendant une campagne de trois mois. La variété de tomate exotique Tropimech a été cultivée avec suivi des paramètres agronomiques, et des échantillons du sol ont été prélevés pour l’extraction et le dénombrement des spores de champignons mycorhiziens arbusculaires (CMA). Le traitement T3 de l’essai 3 (soit 150% de la fiente de volaille plus matière organique) est le plus efficace parmi les traitements, avec 38 t ha-1 pour le rendement en fruits, 13 t ha-1 de rendement pour la partie foliaire et 6 t ha-1 pour la partie racinaire. Les principaux genres de spores CMA trouvés sont des Glomus sp, Gigaspora sp et Scutellospora sp. La densité de Scutelospora sp est aussi plus élevée pour le traitement avec fiente de volaille, avec une forte corrélation positive entre la densité des spores et les paramètres agronomiques. Les résultats ont montré que les fumures, en particulier la fiente de volaille, améliorent la fertilité du sol de cette région ainsi que la densité des spores CMA.

La pêche à l’électricité est une méthode classiquement utilisée pour les inventaires de biodiversité des poissons et crustacés dans le cadre de la surveillance réglementaire de l’état écologique des cours d’eau. Elle pose un certain nombre de difficultés en territoires ultramarins tropicaux, de par certaines spécificités physiques (conductivité de l’eau basse à très basse) et écologiques (communautés mixtes de poissons et de crustacés, biodiversité forte à très forte) qui les caractérisent. Issues du partenariat OFB-INRAE, les recherches menées en collaboration avec l’entreprise HYDRECO-Guyane ont permis de définir des conditions spécifiques d’application de la pêche à l’électricité pour les petits cours d’eau (< 6 mètres de large) tropicaux. Grâce à des essais au laboratoire et in situ, en Guyane, aux Antilles et à La Réunion, nous avons identifié les réglages électriques les plus efficaces pour la capture, l’estimation de la richesse spécifique et de l’abondance des espèces et le respect de la santé animale. Ces recherches se placent dans l’objectif plus large d’améliorer la qualité des données bancarisées pour le suivi environnemental des masses d’eau. Elles donnent lieu à des recommandations pour la maitrise d’œuvre et la maitrise d’ouvrage de la pêche à l’électricité en petits cours d’eau tropicaux.

On February 2nd 2021, a Cuvier’s beaked whale (Ziphius cavirostris) stranded on the île de Ré (Northeast Atlantic, France). Preliminary analyses revealed that the death of the animal was probably caused by anthropogenic noise. Produced in the direct vicinity of an area where military tests were carried out by a vessel, this accident occurred within a marine protected area. This event became the starting point of an investigation aiming to trace its origin, and served as a basis for a broader collaborative work as part of the interdisciplinary research program of Esprit de Velox, Destination Ocean. At the confluence of several disciplines, our reflection highlights, through the lens of human-induced noise impacts on cetaceans, the complexity of the relationships between oceanic life and anthropic activities. In order to better understand and protect the ocean, we advocate for changes in the practices of ocean-related knowledge production, improvement of the legal norms governing the use and protection of the marine environment, and a transformation of our own anthropological relationship to the ocean., Le 2 février 2021, une baleine à bec de Cuvier (Ziphius cavirostris) s’échoue sur l’île de Ré (Atlantique nord-est, France). Les analyses préliminaires révèlent que la mort de l’animal est vraisemblablement liée à des bruits anthropiques. Le lieu probable de la mort de l’animal se situe à proximité directe d’une zone où un navire militaire effectuait des essais au sein d’une aire marine protégée. Point de départ d’une enquête visant à en retracer l’origine, cet événement cristallise la complexité des relations entre vie océanique et activités anthropiques. Il sert de point d’appui à une réflexion collaborative plus large à la confluence de plusieurs disciplines, en vue de faire évoluer la production des savoirs océaniques, les normes juridiques qui encadrent les usages et la protection du milieu marin, et notre rapport anthropologique à l’océan.

En Afrique de l’Ouest, les écosystèmes marins sont menacés par toute une série de pressions humaines, notamment le changement climatique, la surexploitation et la destruction des habitats. La perte d'espèces et de biodiversité qui en résulte peut entraîner des changements brusques et potentiellement irréversibles dans leur structure et leur fonctionnement. Ainsi, des groupes de travail ont été organisés dans le cadre du WP4 du projet DEMERSTEM, en vue d’estimer des indicateurs écosystémiques dans la sous-région ouest africaine sur les quatre dernières décennies. Ainsi 10 indicateurs écologiques sont calculés à partir des données de campagnes scientifiques et 05 indicateurs également calculés à partir des statistiques de pêche. En plus de ces indicateurs, d’autres descripteurs généraux des pêcheries (captures globales par ZEE et effort de pêche) ont été compilés à partir des données nationales disponibles et de la littérature et sont présentés dans le document. Le calcul de ces indicateurs a été fait sur trois (3) cas d’étude, à savoir la ZEE de la Mauritanie, la ZEE du Sénégal et la ZEE de la Guinée. Chacun de ces indicateurs a été présenté par pays et comparé entre eux pour une analyse à l’échelle régionale. Les résultats obtenus montrent que l'évaluation comparative des trois écosystèmes marins étudiés indique que la structure des écosystèmes d'Afrique de l'Ouest est différente, ce qui prouve les différents niveaux d'exploitation selon le système de gestion de la pêche. Les résultats de l'analyse des indicateurs montrent un état relativement stable de la biomasse et de la biodiversité dans la zone ouest-africaine. L'analyse des résultats recommande la mise en oeuvre d'une gestion écosystémique des pêches qui respecte la durabilité des ressources et l'état de santé des écosystèmes en Afrique de l'Ouest.

Due to the lack of studies about the sociocultural dimension of ecosystem services, we analyze in this work the perception of these benefits by family farmers who have agroforestry systems in the northeast of Pará, in the Amazon region. With this objective, we categorize forest restoration strategies based on primary data collection - interviews, semi structured questionnaire, illustrated questionnaire and Likert Scale. Through the relative perception based on the application of Likert scales, we observed that the farmers recognize the benefits provided by agroforest systems and natural landscapes, with high perception of ecosystem services in all the categories present in the Millennium ecosystem evaluation. Furthermore, the higher perceptions of ecosystem services are related to the group of farmers with a smaller area of forest reserve and bigger area of agroforest systems. The result suggests that loss of forest area, at the individual level, probably drives to a higher sense of the benefits of natural systems and thus, the increment in agroforestry systems constitutes an attempt to return to functions and benefits lost through environmental degradation over time. In general, support programs are necessary to strengthen the capacity of agroforestry systems to provide ecosystem services and increase biodiversity conservation.

On oceanic islands, strong human impacts on habitats, combined with introductions of exotic species, modify the composition of terrestrial bird assemblages and threaten their ecological functions. In La Réunion, an oceanic island located in the Madagascan region, a national park was established in 2007 to counter the ecosystem-level effects of three centuries of habitat conversion, native species destruction and exotic species introductions. Here, we investigated how bird assemblages were structured in these human-modified landscapes, 10 years before the national park set out its first conservation measures. We used a combination of multivariate statistics and generalized additive models to describe variations in the taxonomic and functional composition and diversity of 372 local bird assemblages, encompassing 20 species, along gradients of habitat composition and configuration. We found that native species were tied to native habitats while exotic species were associated with urban areas and man-modified landscape mosaics, with some overlap at mid-elevations. Species' trophic preferences were segregated along habitat gradients, but ecological traits had an overall weak role in explaining the composition of species assemblages. Hence, at the time of the survey, native and exotic species in La Réunion formed two spatially distinct species assemblages with contrasting ecological trait suites that benefited from antagonistic habitat compositions and dynamics. We conclude that our results support the analysis of historical data sets to establish reference points to monitor human impacts on insular ecosystems.

Human activities have a growing impact on global biodiversity. While our understanding of biodiversity worldwide is not yet comprehensive, it is crucial to explore effective means of characterizing it in order to mitigate these impacts. The advancements in data storage, exchange capabilities, and the increasing availability of extensive taxonomic, ecological, and environmental databases offer possibilities for implementing new approaches that can address knowledge gaps regarding species and habitats. This enhanced knowledge will, in turn, facilitate improved management practices and enable better local governance of territories. Meeting these requirements necessitates the development of innovative tools and methods to respond to these needs. Citizen science platforms have emerged as valuable resources for generating large amounts of biodiversity data, thanks to their visibility and attractiveness to individuals involved in territorial management and education. These platforms present new opportunities to train deep learning models for automated species recognition, leveraging the substantial volumes of multimedia data they accumulate. However, effectively managing, curating, and disseminating the data and services generated by these platforms remains a significant challenge that hinders the achievement of their objectives. In line with this, the GUARDEN and MAMBO European projects aim to utilize the Pl@ntNet participatory science platform (Affouard et al. 2021) to develop and implement novel computational services to enable the widespread creation of floristic inventories. In the pursuit of this project, various standards and reference datasets have been employed, such as the POWO (Plants of the World Online) world checklist and the WGSRPD (World Geographical Scheme for Recording Plant Distributions) standard, to establish a foundation for creating a global service that aids in plant identification through visual analysis. This service relies on a NoSQL (Not Only St

To document and halt biodiversity loss, monitoring, quantifying trends and assessing management and conservation strategies on wildlife populations and communities are crucial steps. With increasing technological innovations, more and more data are collected and new quantitative methods are constantly developed. These rapid developments come with an increasing need for analytical skills, which are hardly accessible to managers. On the other hand, researchers spend more and more time on research grant applications and administrative tasks, which leaves fewer opportunities for knowledge transfer. This situation tends to increase the gap between researchers and managers. Here, we illustrate how to fill this gap by presenting two long-term collaborations between a research unit—Centre for Functional and Evolutionary Ecology; CEFE—and a national agency—French Biodiversity Agency; OFB. The first example is a collaboration providing statistical support to national parks for the design and implementation of scientific monitoring protocols. It relies on the recruitment of a research engineer funded by OFB and physically based at CEFE, who works closely with OFB and managers. The second example is a collaboration on the management of large carnivores. For more than 10 years, it has involved several PhD students and post-doctoral fellows co-supervised by CEFE and OFB, and has recently resulted in the recruitment of a permanent OFB researcher who works half-time at CEFE and half-time at OFB. These case studies illustrate the modalities of collaborative work between public institutions acting at different levels of biodiversity conservation for the co-construction of research agendas and the exchange of knowledge. These collaborations also bring out some challenges. Inter-knowledge and mutual learning remain difficult at scales larger than that of the teams concerned. The staff working at this interface needs to possess good listening skills, respect all partners' needs and demo

Les milieux humides font partie des écosystèmes les plus menacés au monde. Dans les paysages boréaux, les milieux humides fournissent des services écologiques précieux et constituent des habitats de qualité pour plusieurs espèces. Dans le nord du Canada, les écosystèmes des milieux humides se transforment sous l’effet combiné des perturbations naturelles, du changement climatique et de l’utilisation des sols par l’humain. Ces territoires nordiques représenteront dans un avenir proche un potentiel croissant d’accès aux ressources naturelles, en particulier pour l’exploitation du bois, le développement hydroélectrique et les activités minières. Par conséquent, il peut en résulter une perte ou une réduction de l’habitat des espèces qui dépendent de certains types de milieux humides. Les milieux humides contenant de petits étangs (< 8 ha) sont particulièrement importants pour plusieurs vertébrés qui choisissent ces habitats pour se reposer, se nourrir et se reproduire, notamment les amphibiens, les oiseaux et les mammifères. Cependant, peu d’études ont porté sur la présence de vertébrés au sein des petits étangs et les connaissances sont donc encore fragmentaires. Nous manquons de connaissances sur les préférences en matière d’habitat, et sur l’influence des facteurs biotiques et abiotiques sur les espèces boréales. L’examen de ces facteurs est une première étape pour aborder la gestion des milieux humides et des espèces associées dans les milieux nordiques. L’objectif général de cette thèse était de comparer l’utilisation des étangs de tourbières et des étangs de castors, et de quantifier l’influence des facteurs qui caractérisent ces habitats, ainsi que les interactions biotiques sur trois groupes de vertébrés: les amphibiens, les oiseaux et les mammifères. La région d’étude est située dans la forêt boréale canadienne, dans la région Eeyou-Istchee Baie James, dans le nord-ouest du Québec. Nous avons échantillonné 38 étangs de tourbières et 12 étangs de castors de mai

Les connaissances sur les relations entre les communautés écologiques et le climat sont importantes pour anticiper les impacts que les changements climatiques auront sur elles. Toutefois, les processus opérant à différentes échelles qui interagissent entre elles compliquent notre compréhension. Les lichens étant étroitement liés aux conditions d’eau et de température de leur environnement, les gradients macro-climatiques peuvent participer à façonner leurs communautés. L’objectif général de notre étude était d’évaluer l’effet d’un gradient climatique sur les communautés de macrolichens. Spécifiquement, nous cherchions à 1) identifier les déterminants de la composition en espèces à l’échelle du site et à l’échelle du substrat le long du gradient climatique, et 2) établir si la richesse spécifique à l’échelle du site et à l’échelle du substrat est déterminée par le gradient climatique. Pour ce faire, nous avons effectué des inventaires de macrolichens sur quatre types de substrats (épinettes, bouleaux, chicots et roches) le long du gradient climatique généré par le lac Supérieur. Nous avons inventorié 54 sites situés à différentes distances de la rive dans les forêts boréales mixtes de la côte nord du lac. Nos résultats ont démontré que la composition à l’échelle du site et à l’échelle du substrat était avant tout déterminée par la latitude. En sus, l’échelle du site était surtout déterminée par la distance du lac Supérieur, tandis que l’échelle du substrat était surtout déterminée par la structure forestière, notamment par le diamètre à hauteur de poitrine (DHP) maximal du site et par le pourcentage de couvert forestier. La distance du lac Supérieur n’avait pas d’impact direct ou indirect sur la richesse spécifique, et ce à aucune des deux échelles. Cependant, les effets des facteurs locaux et des variables liées aux substrats étaient moindres près du lac. Nos résultats soulignent l’importance de considérer l’échelle spatiale dans l’analyse de la composition en espèc

The distribution of plant communities in hot desert ecosystems is discontinuous and resembles the pattern of heterogeneous resource patches, known as “fertility islands”. Understanding the key factors that allow plants to establish in these conditions, as well as their associated microbial diversity, is crucial to the comprehension and preservation of these ecosystems. Saudi Arabia in the Arabian Peninsula, is one of the driest regions in the world, with a very low water regime and low soil nutrient contents. The establishment of ecosystems in these arid desert conditions is therefore subject to numerous constraints. Understanding the biotic and abiotic factors linked to the formation of fertility islands, from the perspective of soil composition and its associated microbiome, both in the soil and in the roots of associated plant community, is therefore a fundamental issue for the preservation of these ecosystems. In this study, we analyzed the soil composition between a fertility island and bare soil. The proportions of micro- and macro-elements important for plant nutrition, namely magnesium, phosphorus, potassium and iron were higher in the fertility island. We also observed that soil bacterial and fungal diversity increased in the fertility island. Key taxa such as Rhizobia and Glomeraceae which play important roles in ecosystem functioning were identified in both the fertility island soil and in the roots of the established plant community. These results confirm that plant establishment is linked to soil conditions, in line with the fertility island hypothesis, and that the microbial community in the fertility island differs both in diversity and in composition from that of the bare soil. Fertility islands soils and the roots of established plant community harbor a microbiome potentially crucial to ecosystem functioning, and are of major interest for conservation and agronomy programs.

Growing pressure from climate change and agricultural land use is destabilizing soil microbial community interactions. Yet little is known about microbial community resistance and adaptation to disturbances over time. This hampers our ability to determine the recovery latency of microbial interactions after disturbances, with fundamental implications for ecosystem functioning and conservation measures. Here we examined the response of bacterial and fungal community networks in the rhizosphere of Haloxylon salicornicum (Moq.) Bunge ex Boiss. over the course of soil disturbances resulting from a history of different hydric constraints involving flooding-drought successions. An anthropic disturbance related to past agricultural use, with frequent successions of flooding and drought, was compared to a natural disturbance, i.e., an evaporation basin, with yearly flooding-drought successions. The anthropic disturbance resulted in a specific microbial network topology characterized by lower modularity and stability, reflecting the legacy of past agricultural use on soil microbiome. In contrast, the natural disturbance resulted in a network topology and stability close to those of natural environments despite the lower alpha diversity, and a different community composition compared to that of the other sites. These results highlighted the temporality in the response of the microbial community structure to disturbance, where long-term adaptation to flooding-drought successions lead to a higher stability than disturbances occurring over a shorter timescale.

The future of most tropical sectors is clouded by growing constraints linked to, among many other parameters, climate change, price volatility and labour scarcity. Perpetuating agricultural systems inherited from the colonial era (a time of abundant arable land, protected markets, and cheap and disciplined labour) will not be enough to prepare these sectors in facing immediate crucial challenges unless substantial structural transformations are made. Implementing a successful agroecological transition in a 70-billion USD sector, covering 25 million ha worldwide, calls for drastic changes in mind-sets and practices. The key issue is no longer simply to increase productivity, but to foster innovations designed to support endangered tropical biodiversity, while providing a decent living for shrinking agricultural communities in the Global South. Agroforestry practices have a role to play in providing substantial climate change mitigation with an impact comparable to other climate-focused solutions, such as reforestation. The expected contribution of oil palm-based agroforestry relies on agro-environmental services, as basic agricultural functions such as soil preservation, pollination, or pest control can be ensured by living organisms inside and around the plantation. Diversified systems are able to achieve both economic and environmental gains, as they use land more efficiently than monocultures. Building on regenerative agriculture, new plantation designs are emerging and deserve to be thoroughly assessed to establish evidence-based advocacy for change.

Agroforestry systems can potentially increase tree diversity within agricultural landscapes, but to date, there is little understanding of the patterns of shade plant diversity within different agroforestry systems (AFS) at large spatial scales. Using compiled plant inventory data (from 23 sources, 2517 plots, and 148,255 individuals) encompassing four AFS (shaded coffee; shaded cocoa; dispersed trees on pastures; and live fences) across six countries in Central America we estimated different metrics of diversity to assess the conservation value of different AFS for shade plants. 458 shade plant species were recorded across the four agroforestry systems. Primary forest species accounted for 28% of the shade species recorded, but only 6% of the recorded individuals. No single AFS was consistently the most diverse across countries when considering rarefied species richness. Trees on pastures can potentially reach a similar species richness as cocoa and coffee systems but require sampled areas 7–30 times larger. In terms of composition, 29 species were shared across the agroforestry systems in different countries, illustrating the strong selection pressure of farmers for species that provide timber, firewood, and fruit. Our study highlights the potential contribution and limitations of different AFS for tree diversity conservation within agricultural landscapes.

Background: The savannah ecosystems of Sahel have experienced continuous and heavy grazing of livestock for centuries but still, their vegetation response to grazing pressure remains poorly understood. In this study, we analysed the herbaceous plant dynamics, measured by species diversity, composition, cover, and biomass in response to grazing pressure in the savannah ecosystems of Sahel. In Senegal, we selected four savannah sites represented with high, moderate, light and no grazing intensity levels. Transect survey methods were used for sampling the vegetation data within each of the sites. Species richness and composition were analysed using species accumulation curve and multivariate analyses. Furthermore, we used General Linear Models and a piecewise Structural Equation Model (pSEM) to examine the relationships between grazing intensity, vegetation cover, diversity and biomass. Results: The herbaceous species diversity and composition varied significantly among the different grazing intensity levels (p <0.001). The plant species composition shifted from the dominance of grass cover to the dominance of forb cover with increasing grazing pressure. Moreover, the attributes of species diversity, herbaceous biomass, and ground cover were higher on sites with low grazing than sites with high and moderate grazing intensity. Across all sites, species diversity was positively related to total biomass. The pSEM explained 37% of the variance in total biomass and revealed that grazing intensity negatively influenced total biomass both directly and indirectly through its negative influence on species diversity. Conclusions: Managing grazing intensity may lead to higher plant production and higher mixed forage establishment in the dryland savannah ecosystems. This information can be used to support land management strategies and promote sustainable grazing practices that balance the needs of livestock with the conservation of ecosystem health and biodiversity.

The Global Plant Health Assessment (GPHA) is a collective, volunteer-based effort to assemble expert opinions on plant health and disease impacts on ecosystem services based on published scientific evidence. The GPHA considers a range of forest, agricultural, and urban systems worldwide. These are referred to as (Ecoregion × Plant System), i.e., selected case examples involving keystone plants in given parts of the world. The GPHA focuses on infectious plant diseases and plant pathogens, but encompasses the abiotic (e.g., temperature, drought, and floods) and other biotic (e.g., animal pests and humans) factors associated with plant health. Among the 33 (Ecoregion × Plant System) considered, 18 are assessed as in fair or poor health, and 20 as in declining health. Much of the observed state of plant health and its trends are driven by a combination of forces, including climate change, species invasions, and human management. Healthy plants ensure (i) provisioning (food, fiber, and material), (ii) regulation (climate, atmosphere, water, and soils), and (iii) cultural (recreation, inspiration, and spiritual) ecosystem services. All these roles that plants play are threatened by plant diseases. Nearly none of these three ecosystem services are assessed as improving. Results indicate that the poor state of plant health in sub-Saharan Africa gravely contributes to food insecurity and environmental degradation. Results further call for the need to improve crop health to ensure food security in the most populated parts of the world, such as in South Asia, where the poorest of the poor, the landless farmers, are at the greatest risk. The overview of results generated from this work identifies directions for future research to be championed by a new generation of scientists and revived public extension services. Breakthroughs from science are needed to (i) gather more data on plant health and its consequences, (ii) identify collective actions to manage plant systems, (iii) e

Sustainability science needs new approaches to produce, share, and use knowledge because there are major barriers to translating research into policy and practice. Multiple actors hold relevant knowledge for sustainability including indigenous and local people who have developed over generations knowledge, methods, and practices that biodiversity and ecosystem assessments need to capture. Despite efforts to mainstream knowledge coproduction, less than 3% of the literature on nature's contributions to people (NCP) integrates indigenous and local knowledge (ILK). Approaches and tools to better integrate scientific and ILK knowledge systems in NCP assessments are urgently needed. To fill this gap, we conducted interviews with ILK experts from Abancay and Tamburco, Peru, and convened focus groups and workshops during which participatory mapping, a serious game, a Bayesian belief network based on ILK were introduced. We inventoried 60 medicinal plants used to treat different illnesses, and analyzed the spatial distribution of the 7 plants that contribute the most to a good quality of life, and delineated their nonmedicinal uses. Based on the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services conceptual framework, we defined dimensions of a good quality of life according to indigenous and local worldviews. Medicinal plants contributed strongly to health and household security, among other contributions. Climate change and overexploitation were the main perceived threats to medicinal plants, despite the existence of formal and customary institutions to regulate trade. Our approach was flexible enough to integrate diverse forms of knowledge, as well as qualitative and quantitative information from, for example, the Bayesian belief network.