HAL-IRD
Not a member yet
83947 research outputs found
Sort by
Conserving and regenerating the High Atlas cultural landscapes: gendered perspectives from the local Amazigh communities
No full textInternational audienceLocal communities play a vital role in conserving biocultural diversity; yet their priorities are seldom considered when designing sustainable measures and actions, particularly in remote areas. These processes are frequently developed from urban perspectives, focusing on regional or national scales, and local social dynamics are often overlooked. In this paper, we explore community-based conservation recommendations to develop a strategy for the cultural landscapes of the High Atlas, integrating insights from both local Amazigh voices and academic perspectives. We conducted focus groups with three representative communities in the High Atlas, involving 92 participants. We first documented the environmental changes that both women and men perceived separately. Next, community members provided recommendations for biocultural diversity conservation, which were further discussed among all participants. The participants' perceived changes and the proposed recommendations varied significantly between villages, even over short distances. These variations emerged from each village's primary livelihood and the types of ecosystems on which they depend. Both men and women noted numerous changes in agriculture, pastoralism, and the economy, and suggested actions to address the negative impacts. Women highlighted positive developments in medicinal practices; however, they also pointed out infrastructural deficiencies that hinder human well-being. These discussions served as the grounds for preparing community action plans that guided biocultural conservation action with these populations. Grounding rural development planning, programming, and monitoring in gendered local perceptions and aspirations is crucial for the resilience and adaptation of these landscapes, the people and other non-human living beings inhabiting them
Spillover from flower plantings benefits apple pollination on a small scale
No full textInternational audienceAnimal-mediated pollination is critical to support crop yields but is threatened by the decline of pollinator populations. The establishment of flower plantings in agricultural landscapes is a conservation strategy that aims to provide diverse floral resources for pollinators. Despite several studies on the effect of flower plantings on pollination, their effects remain unclear. In particular, the influence of the distance has been studied through theoretical approaches but field studies are scarce. We conducted field experiments over two years, 2023 and 2024, in the Provence-Alpes-Côte d'Azur region of France, to investigate how co-flowering plantings affect insect flower visitation and crop pollination in apple orchards. We found that the abundance of apple flower visitors, especially wild bees, decreased with the distance from flower plantings, thus suggesting a spillover of flower visitors from flower plantings into adjacent apple trees. Interestingly, we found a non-linear effect of the distance from flower planting on the initial fruit set, which suggests that flower plantings can improve apple pollination at close distances from the plantings (about 33 m). No effect of the distance from flower plantings was observed on the diversity of flower visitors, final apple fruit set or fruit quality. Overall, our results suggest that flower plantings are a promising strategy to support pollinators. Furthermore, as they can increase pollinator abundance in the adjacent apple flowers, flower plantings have the potential to enhance pollination and yield of the adjacent crops. Given the short distance of the observed facilitation effect, we recommend that flower plantings should be spread across farmland in order to promote crop pollination at farm level
Microbial life in Arctic pack ice: Prospects for the Tara Polaris expeditions
No full textInternational audienceSea ice, unlike freshwater ice, hosts abundant microbial life, thanks to the presence of liquid water inclusions encased within the ice matrix. The forthcoming Tara Polaris Expeditions (TPE), which will document drifting Arctic pack ice repeatedly over multiple years, together offer an unprecedented opportunity to advance understanding of the sea-ice microbiome -its diversity, variations, and ecological roles. In this contribution, we consider the current state of knowledge, identify key research gaps, and outline the potential for progress enabled by TPE. We envision the emergence of new insights into the seasonal evolution of microbial life, resolved at the floe (kilometric) scale, in relation to the evolution of the sea-ice environment -its morphology, light, temperature, and liquid water distribution and properties. Large potential lies in the characterization of diverse microhabitats across the central Arctic Ocean, associated with brine inclusions, pressure ridge cavities, and melt ponds. A major goal will be to document biological processes that remain poorly understood -colonization, diversity, functioning, interactions, and evolutionary dynamics -and that could benefit from the application of newly developed techniques. We argue that TPE is particularly timely, as the loss of multi-year ice may soon constrain opportunities to study life in this rapidly changing habitat
Biopesticide Production from Trichoderma harzianum by Solid-State Fermentation: Impact of Drying Process on Spore Viability
No full textInternational audienceAmong the sustainable agricultural approaches, biological control agents are a promising new alternative to agrochemicals. However, expensive production methods, formulation, poor storage stability and short shelf life are limiting their adoption. One of the promising options for biopesticide production is solid-state fermentation (SSF). This study was conducted to evaluate spore production by two Trichoderma harzianum, Rey 3 and TF2, under forced air drying in SSF. A mixture of agroindustrial byproducts (sugarcane bagasse, vine shoots, wheat bran, potato flour and chitin) were used as substrates. CO 2 generated during fungi growth was recorded by respirometry. We also investigated the effect of hydric stress conditions on the decreasing phase of Trichoderma metabolism as an inducer of sporulation. In parallel, we analyzed the viability of T. harzianum TF2 and spores under different storage conditions (lyophilized, frozen and dried). Under the present culture conditions, the highest production of spores was 10.1 ± 0.3 × 10 9 spores/g DM (Dry Material) at 52 h for T. harzianum Rey 3 and 8.9 ± 0.6 × 10 9 spores/g DM at 72 h for T. harzianum TF2. The forced dry air during the fermentation process had no notable effect on spore production, but it did increase the spore viability (29% viability for T. harzianum Rey 3 and 33% viability for T. harzianum TF2). In parallel, the chitinase, cellulase, xylanase and lipase activities were evaluated, obtaining interesting results regarding enzymatic activities.</div
Disentangling Eastern Pacific Warming: El Niño 2023–2024 vs seasonal Panamá Bay influence
No full textInternational audienceUnderstanding the drivers of coastal ocean warming in the eastern Pacific is critical for distinguishing local variability from large‑scale climate phenomena such as El Niño. This study tests the hypothesis that anomalous warming in northern Ecuadorian coastal waters during January 2024 was primarily driven by the seasonal intrusion of Panamá Bay waters rather than the developing 2023–2024 El Niño event. Oceanographic and meteorological data were collected aboard the Pourquoi Pas? research vessel and compared against climatology (1940–2024), the 1997–1998 El Niño, and satellite observations. Winds were predominantly south-westerly, exceeding climatological averages while sea surface temperatures showed a pronounced south–north gradient. Salinity and mixed‑layer depths remained within seasonal ranges. The Intertropical Convergence Zone persisted north. Comparative analysis revealed weak or absent El Niño signals, with no discernible climatic impacts, wind, rain, thermocline and 20 C depths, T/S relationships, which were within seasonal values corroborated with biological and meteorological indicators. Instead, the seasonal incursion of Panamá Bay waters was the dominant warming driver. These findings refine understanding of eastern Pacific variability and provide the first deep profiles from this region, including serendipitous evidence of Antarctic Intermediate Water at ~1000 m, thereby enhancing observational coverage in a historically undersampled area
Transcriptomic plasticity in hybrid schistosomes can contribute to their zoonotic potential
No full textInternational audienceHybrids between Schistosoma haematobium and Schistosoma bovis contribute to human and animal infections, highlighting complex interspecies interactions that facilitate schistosomiasis transmission. Schistosoma bovis infects multiple ruminant hosts, promoting cross-species transmission and increasing zoonotic risk. This study explores transcriptomic plasticity as a mechanism enabling hybrid schistosomes to adapt to different definitive hosts. We analysed two contexts: (1) introgressed S. haematobium × S. bovis hybrids, which exhibited higher virulence in sheep than parental S. bovis; and (2) S. bovis infecting different mammalian hosts. Introgression, the transfer of genetic material between species through hybridization and repeated backcrossing, was associated with 366 differentially expressed genes (4% of coding genes) between introgressed hybrids and S. bovis in sheep. Additionally, S. bovis showed host-dependent transcriptomic changes, with 30% of genes differentially expressed between infections in hamsters and sheep. Enriched biological processes shared across introgression and host adaptation included nuclear mRNA catabolism and inner mitochondrial membrane organization, indicating increased gene expression plasticity and metabolic adaptation to environmental stress. These findings suggest that transcriptomic plasticity enhances the adaptability of S. bovis and hybrid worms, increasing their zoonotic potential. This raises concerns for schistosomiasis control, as such plasticity could expand transmission capacity and complicate intervention strategies.This article is part of the Royal Society Science+ meeting issue ‘Parasite evolution and impact in action: exploring the importance and control of hybrid schistosomes in Africa and beyond’
Growth Rate and Energy Dissipation in Wind‐Forced Breaking Waves
No full textInternational audienceWe investigate the energy growth and dissipation of wind‐forced breaking waves at high wind speed using direct numerical simulations of the coupled air–water Navier–Stokes equations. A turbulent wind boundary layer drives the growth of a pre‐existing narrowband wave field until it breaks, transferring energy into the water column. Under sustained wind forcing, the wave field resumes growth. We separately analyze energy transfers during wave growth and breaking‐induced dissipation. Energy transfers are dominated by pressure input during growth and turbulent dissipation during breaking. Wind input during growth is balanced with dissipation during breaking over an entire growing‐breaking cycle. The wave growth rate scales with , modulated by the wave steepness due to sheltering, and the energy dissipation follows the inertial scaling with wave slope at breaking, confirming the universality of the process. Following breaking, near‐surface vertical turbulence dissipation profiles scale as , with their magnitude controlled by the breaking‐induced dissipation
Tara Polaris expeditions: seasonal and long-term contaminant monitoring in the changing central Arctic
No full textInternational audienceThe central Arctic atmosphere, cryosphere, hydrosphere and biosphere, is heavily impacted by anthropogenic activities. While some contaminants originate from local activities, the majority are transported over long distances via rivers, ocean currents, and atmospheric pathways. Contaminants can have adverse effects on the environment, ecosystems, and human health, which are expected to intensify with continued emissions and warming climate. This article outlines the objectives for new studies on contaminants in the Arctic Ocean, in particular during the Tara Polaris expedition, with an emphasis on year-round long-term contaminant dynamics and associated ecotoxicological risks. Mercury contamination remains a major concern in the Arctic, especially in the form of methylmercury, which is primarily produced by marine microbes. Methylmercury bioconcentrates, bioaccumulates and biomagnifies to harmful levels in Arctic wildlife and threatens indigenous communities. Anthropogenic lead (Pb), though low in Arctic waters, remains toxic and may be remobilized by climate change. Plastic pollution, from nano-to macro-scales, is widespread across all Arctic compartments, closely interacting with planktonic communities and posing ingestion risks to invertebrates, fish, seabirds and mammals (including humans). Chemicals of Emerging Arctic Concern (CEAC), including newly recognized persistent organic pollutants inherited from past industrial activities (e.g., per-and polyfluoroalkyl substances (PFAS)), are more recalcitrant in the environment than many other synthetic compounds, raising serious questions about their long-term ecological and health effects. In this context, the Tara Polaris expeditions aim to produce high-resolution, year-round observational data in the central Arctic to deepen our understanding of contaminant sources, transport, internal cycling and environmental fate. These data will also support the development and refinement of numerical models for contaminant dynamics in the context of both Arctic and global environmental change
Improving the Late Devonian plant record of Australia : A Frasnian assemblage from Gooloogong, New South Wales
No full textInternational audienceFor Devonian palaeobotany, Australia represents one of the most geologically welldocumented areas of the understudied Gondwana palaeocontinent. Despite this asset, the Australian plant record is still insufficiently known for this period. This situation is detrimental to a satisfactory understanding of the evolution and diversification patterns of vascular plants at a crucial moment in Earth's history, when they acquired modern attributes and when the main extant lineages originated.This paper documents a plant assemblage from a locality near the town of Gooloogong in central New South Wales, based on fossils collected by A. Ritchie and R. Jones of the Australian Museum, Sydney, in 1973. Additional material was collected in 2004 by our team. Fossils are preserved in the form of casts, adpressions preserving external morphology, and permineralizations showing internal anatomy. The Lycopsida are represented by Leptophloeum rhombicum, the Cladoxylopsida by Denglongia cf. hubeiensis, and the Progymnospermopsida by various organs attributed to the Archaeopteridales, i.e. a root of Callixylon sp., branches of Archaeopteris sp., and a leaf of Archaeopteris macilenta.This association, which is typical of the Frasnian of South China supports a Frasnian age for the Gooloogong plant assemblage. It also confirms the existence of floristic exchanges between the northeastern part of Gondwana and South China at this time, and supports a trend towards the homogeneization of floras during the Late Devonian
Receptiveness of the wine industry to fungus-resistant grape varieties in the south of France
No full textInternational audienceThe adoption of fungus-resistant grape varieties (FRGs) represents a promising pathway for steering viticulture towards more sustainable production methods by reducing the use of phytosanitary inputs. At the time of writing, the dissemination of these varieties remains limited, partly due to constraints within the wine industry (i.e., cost of planting and cultivar limitations associated with Protected Designation of Origin). This study was conducted with commercial wines made from two types of grape: Vitis vinifera and FRGs. A panel of 96 participants from the wine industry in the Occitanie region (south of France) conducted sensory evaluations. The panel performed the evaluations both blind and having been informed about type of grape in a combination of short CATA (Check-All-That-Apply) sessions followed by questions exploring their interest in FRGs and expected plantations in the coming years. The results of the sensory analyses underlined the absence of any notable difference in liking or in the sensory profiles of the wines, whether tasted blind or not. Indeed, disclosure of the type of grape used to make the wines did not alter participants' perceptions or evaluations. Furthermore, the analysis of questionnaire data revealed a typology of three adopter profiles: i) "Sceptics": older professionals from private wineries who were generally unfavourable towards the adoption of FRGs, ii) "Receptives": cooperative members who showed measured support for innovation, and iii) "Observers": young, non-decision-making individuals with heterogeneous opinions. This industry panel predicted that there could be 25 % of vineyard areas planted with FRGs in Occitanie within the coming 30 years. This study offers insights into the future adoption of this new plant material within the wine industry