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Drought‐driven foraging adjustments in breeding white storks Ciconia ciconia : GPS tracking insights from two French marshes
No full textInternational audienceIn the context of climate change, the increasing frequency of severe meteorological events, such as floods or droughts, is expected to impact various life history traits in organisms, primarily by altering the availability and quality of their trophic resources. Our study aimed to quantify the effects of meteorological conditions on the fine‐scale space use of breeding white storks Ciconia ciconia . Birds were equipped with GPS/acceleration loggers in two breeding areas within the marshes of the French Atlantic coast and monitored over four years, including one year of drought. Specifically, we examined variations in home‐range size, daily foraging distances, the proportion of time spent foraging, and daily activity levels in relation to drought conditions and individual state (sex, brood age and brood size). Our findings reveal that under drier conditions, storks increased their daily foraging distances, home‐range size, and time spent foraging. Individuals with smaller broods travelled greater distances from the nest, and tended to exploit larger home‐ranges. Their activity levels and time spent foraging increased with brood age and brood size, and were higher in females than in males. Our findings reveal how climate change, particularly drought, affects the foraging behaviour of a wetland top predator, and highlight the conservation challenges faced by wetland ecosystems
Why do firms issue green bonds?
No full textNational audienceCorporate green bond announcements generate positive abnormal stock returns. We suggest this might be because managers use green bonds to signal the profitability of the climate-friendly projects they finance. First, we build a signaling model of green bond issuance. It predicts that firms’ incentives to decarbonize are amplified by the interest of their managers in their stock price. Second, we provide supporting empirical evidence, using cross-country variations in effective carbon prices, and cross-industry differences in the stock-price sensitivity of managers’ compensation. Our results suggest that green bonds are not substitutes for but rather complements to carbon pricing
Communal studies and intentional communities: key features and main contributions to the understanding of the social and solidarity economy
No full textInternational audienceThis chapter situates intentional communities, including ecovillages, kibbutzim, communes, and other utopian communities, within the realm of the social and solidarity economy (SSE), while also presenting the original contributions of communal studies to the theoretical understanding of this field. As a specific type of organization within the SSE, intentional communities, which bring together a group of individuals who share some or all of their goods and resources, shed light on two main questions: first, the commitment of members to the organization, and second, how to assess the success of organizations beyond the question of longevity
On the impact of the rheological and tribological properties of thickened drinks on perceived texture
No full textThickened drinks are widely used to improve drinking safety for dysphagic patients, but palatability can be compromised, reducing acceptance. This study investigates the effect of the drink formulation, by including different thickeners, on texture perception by integrating a sensory, a rheological, and a tribological characterization using a tongue-mimicking surface. The friction coefficient at a characteristic, in vivo-like, sliding velocity of about 10 mm•s -1 was shown to strongly correlate with the perceived graininess. In addition, the viscosity at a characteristic shear rate of ≈ 179 s -1 was identified as a good predictor of perceived thickness. The sensory results were also put in the context of the IDDSI consistency classification. Each IDDSI level comprises beverages with significantly different rheological and tribological behaviors, and this study confirms that consumers can perceive such differences
Environmental Assessment for Upscaling: an LCA-based eco-design process for design teams
No full textInternational audienceThe upscaling of technologies is a socio-technical phenomenon covering technological development and deployment in society to meet societal imperatives (e.g. sustainability). It is characterized by five archetypes, each encompassing specific design practices and models referring to a great variety of consequences on industrial systems. However, these upscaling archetypes are not addressed in current eco-design practices, and even less so in a unified way. This research paper, based on a literature review on LCA, upscaling, and eco-design, presents a new LCA-based design process, titled Environmental Assessment for Upscaling (EAU). This methodological contribution constitutes upscaling environmental assessment guidelines for design team stakeholders (e.g. technical expert, lifecycle expert, company manager). Its originality is to propose a structure favouring the emergence of an accurate consideration of the environmental aspects of the upscaling with an aggregated approach of the upscaling archetype modelling. The EAU process clarifies the main points of interest in the LCA practices related to upscaling assessment from various LCA communities. This methodology follows six necessary steps, and relies on original and interlinked categories of upscaling parameters, enabling design teams to consider the upscaling as a whole during the eco-design process. Four additional resources to guide design team stakeholder collaboration are presented in parallel, with a focus on lifecycle engineering. Finally, the operationalization of the EAU process is discussed considering the LCA standard as a vector of integration in companies. Reinforcing the EAU process’ use could help design teams manage sustainability consistently and support the necessary ecological shifts at the company level
Do carbon emissions affect the cost of capital?
No full textNational audienceWe empirically study whether carbon emissions affect firms’ cost of capital raised on conventional bond markets. We find that firms with higher carbon emissions face higher spreads in the secondary market but not in the primary market. We show that this gap is related to uncertainty about climate concerns that affects differently primary and secondary market. This gap is also affected by the reputation of underwriting dealers: high reputation promotes the incorporation of climate concerns into bond yields. Our findings imply that, on average, carbon emissions do not affect the cost of capital in bond markets, thereby reducing firms’ financial incentives for decarbonization
Do stomatal movements have a limited dynamic range?
No full textStomatal movements are driven through the uptake and release of potassium (K + ) salts by guard cells, which surround a central pore. The extrusion of K + from guard cells occurs via GORK K + -efflux channels, but potentially the AtKUP2, 6 and 8 encoded K + - transporters also play role. To test the roles of At KUP and GORK proteins, gas-exchange experiments were conducted with mature Arabidopsis leaves. These experiments revealed that loss of KUP2, 6 and 8 lowered the stomatal conductance, while it increases in the GORK loss-of function mutant. Despite the difference in stomatal conductance, the changes in transpiration induced by light and ABA had the same amplitude in wild type and mutant lines. Our data suggest that stomata have a limited dynamic range that is not affected by mutations in KUP2, 6 and 8, or GORK. We propose that these rapid stomatal movements depend on uptake and release of K + , inorganic and small organic anions. Consequently, changes in stomatal opening beyond the dynamic range will depend on osmolytes that cannot be rapidly released, such as larger organic anions and amino acids
Born to be alive. Isotopic evidence of investment in the survival of immature individuals in the Neolithic period, ecological influences and the construction of social identities
No full textInternational audienc
The contributions of various calcifying plankton to the South Atlantic calcium carbonate stock
No full textInternational audiencePelagic calcifying plankton play an important role in the marine carbon cycle. However, field studies quantifying the contributions of multiple calcifying plankton groups to particulate inorganic carbon (PIC) stocks and export into the ocean interior are scarce. Most studies target one specific plankton group and adjust their sampling strategy accordingly, hampering comparisons. Furthermore, the literature is strongly biased towards foraminifera and coccolithophores, so aragonite contributions (e.g., gastropods) remain virtually unconstrained. A holistic view is required for future projections of marine carbon cycle changes. Here, we present the contributions of three main calcifying plankton groups – coccolithophores, foraminifera and planktonic gastropods (comprising heteropods and pteropods) – to PIC stocks and fluxes throughout the water column during a sampling campaign in the South Atlantic Ocean. Coccolithophore calcite dominated the depth-integrated PIC standing stock (∼ 80 %), followed by aragonite from planktonic gastropods (∼ 17 %) and calcite from foraminifera (∼ 3 %). The estimated production and export of the calcifying plankton largely depend on assumed turnover times and sinking speeds, which both have large uncertainties. Coccolithophores contributed 92 %–99 % of the produced PIC, depending on planktonic gastropod turnover time, and from 52 % to 99 % of the exported PIC, depending on their mode of sinking. Both the standing stock and export of planktonic gastropods was significantly larger than that of foraminifera. Similarity between our results and those from different ocean basins suggests that these patterns are global in nature, implying that not only coccolithophores but also gastropods may be a more important contributor to the oceans PIC inventory than foraminifera, challenging a longstanding paradigm
Top-down scale approaches for multiscale GWR with locally adaptive bandwidths
No full textInternational audienceSpatially varying coefficient models are widely used in fields such as housing markets, land use, ecology, and seismology, where capturing spatial heterogeneity is essential. Compared to standard Geographically Weighted Regression (GWR), Multiscale Geographically Weighted Regression (MGWR) improves estimation by allowing each covariate to operate at its own spatial scale. Yet, MGWR relies on a backfitting algorithm that limits scalability to moderate datasets and leaves predictive performance largely unexplored. We propose the Top-Down Scale approach for MGWR, which introduces a structured sequence of decreasing bandwidths within the backfitting process. This avoids full re-optimization at each step, substantially reducing computational costs while improving reliability of the global optimum. The resulting algorithm, tds_mgwr, handles up to 50,000 observations and 20 covariates efficiently, combining speed with accurate estimation and enabling more flexible and accurate modeling of complex spatial patterns. We also introduce the Adaptive Top-Down Scale approach for MGWR (atds_mgwr), which incorporates a gradient boosting-like stage to refine covariate bandwidths sequentially. This captures multiple spatial scales simultaneously, moving beyond the notion of a single optimal bandwidth. Monte Carlo experiments show that tds_mgwr achieves fast convergence and high accuracy, while atds_mgwr excels in complex multiscale settings. However, applications to real datasets suggest that predictive gains from MGWR over single-scale GWR are often modest, underlining the need for careful cross-validation and AICc-based validation when adopting multiscale models