Alternative regeneration of chemicals employed in mineral carbonation towards technology cost reduction

AbstractMineral carbonation (MC) using recyclable ammonium salts pH swing processes is considered among the most promising MC techniques to store CO2 permanently. However, the main key challenge to use this process at large scale is related to the energy consumption associated to the regeneration of the employed additives and in particular to the separation of the salt to be regenerated from the water solution.This work investigates the feasibility of a liquid-liquid extraction technique to replace the energy intensive salts/water separation step. Also, the CO2-balance of a 500MW coal-fired based power plant with an integrated pH swing MC facility was investigated. Different operating conditions were investigated, including temperature, reaction time, pressure, solid to liquid ratio (S/L), reagents concentration and stirring rate. An ammonium sulphate/water separation higher than 90% was achieved at 25°C, 10min, 1bar, 200g/lS/L ratio, 70% methanol and, 350rpm. The associated energy consumption was calculated, resulting in an energy saving of 35% in comparison to water evaporation. The process resulted carbon negative when water evaporation was replaced by extraction technique, with 33% of CO2 sequestered by using a S/L ratios of 300g/l

Seagrass structural and elemental indicators reveal high nutrient availability within a tropical lagoon in Panama

Seagrass meadows are valued coastal habitats that provide ecological and economic benefits around the world. Despite their importance, many meadows are in decline, driven by a variety of anthropogenic impacts. While these declines have been well documented in some regions, other locations (particularly within the tropics) lack long-term monitoring programs needed to resolve seagrass trends over time. Effective and spatially-expansive monitoring within under-represented regions is critical to provide an accurate perspective on seagrass status and trends. We present a comprehensive dataset on seagrass coverage and composition across 24 sites in Bahía Almirante, a lagoon along the Caribbean coast of Panama. Using a single survey, we focus on capturing spatial variation in seagrass physical and elemental characteristics and provide data on key seagrass bio-indicators, such as leaf morphology (length and width), elemental content (% nitrogen and phosphorus) and stable isotopic signatures (δ13C and δ15N). We further explore relationships between these variables and water depth (proxy for light availability) and proximity to shore (proxy for terrestrial inputs). The seagrass assemblage was mostly monospecific (dominated by Thalassia testudinum) and restricted to shallow water (\u3c3 m). Above-ground biomass varied widely, averaging 71.7 g dry mass m-2, yet ranging from 24.8 to 139.6 g dry mass m-2. Leaf nitrogen content averaged 2.2%, ranging from 1.76 to 2.57%, while phosphorus content averaged 0.19% and ranged from 0.15 to 0.23%. These values were high compared to other published reports for T. testudinum, indicating elevated nutrient availability within the lagoon. Seagrass stable isotopic characteristics varied slightly and were comparable with other published values. Leaf carbon signatures (δ13C) ranged from -11.74 to -6.70h and were positively correlated to shoreline proximity, suggesting a contribution of terrestrial carbon to seagrass biomass. Leaf nitrogen signatures (δ15N) ranged from -1.75 to 3.15h and showed no correlation with shoreline proximity, suggesting that N sources within the bay were not dominated by localized point-source discharge of treated sewage. Correlations between other seagrass bio-indicators and environmental metrics were mixed: seagrass cover declined with depth, while biomass was negatively correlated with N, indicating that light and nutrient availability may jointly regulate seagrass cover and biomass. Our work documents the response of seagrass in Bahía Almirante to light and nutrient availability and highlights the eutrophic status of this bay. Using the broad spatial coverage of our survey as a baseline, we suggest the future implementation of a continuous and spatially expansive seagrass monitoring program within this region to assess the health of these important systems subject to global and local stressors

Expert range maps of global mammal distributions harmonised to three taxonomic authorities

AimComprehensive, global information on species' occurrences is an essential biodiversity variable and central to a range of applications in ecology, evolution, biogeography and conservation. Expert range maps often represent a species' only available distributional information and play an increasing role in conservation assessments and macroecology. We provide global range maps for the native ranges of all extant mammal species harmonised to the taxonomy of the Mammal Diversity Database (MDD) mobilised from two sources, the Handbook of the Mammals of the World (HMW) and the Illustrated Checklist of the Mammals of the World (CMW).LocationGlobal.TaxonAll extant mammal species.MethodsRange maps were digitally interpreted, georeferenced, error-checked and subsequently taxonomically aligned between the HMW (6253 species), the CMW (6431 species) and the MDD taxonomies (6362 species).ResultsRange maps can be evaluated and visualised in an online map browser at Map of Life (mol.org) and accessed for individual or batch download for non-commercial use.Main conclusionExpert maps of species' global distributions are limited in their spatial detail and temporal specificity, but form a useful basis for broad-scale characterizations and model-based integration with other data. We provide georeferenced range maps for the native ranges of all extant mammal species as shapefiles, with species-level metadata and source information packaged together in geodatabase format. Across the three taxonomic sources our maps entail, there are 1784 taxonomic name differences compared to the maps currently available on the IUCN Red List website. The expert maps provided here are harmonised to the MDD taxonomic authority and linked to a community of online tools that will enable transparent future updates and version control

Dire wolves were the last of an ancient New World canid lineage

Dire wolves are considered to be one of the most common and widespread large carnivores in Pleistocene America1, yet relatively little is known about their evolution or extinction. Here, to reconstruct the evolutionary history of dire wolves, we sequenced five genomes from sub-fossil remains dating from 13,000 to more than 50,000 years ago. Our results indicate that although they were similar morphologically to the extant grey wolf, dire wolves were a highly divergent lineage that split from living canids around 5.7 million years ago. In contrast to numerous examples of hybridization across Canidae2,3, there is no evidence for gene flow between dire wolves and either North American grey wolves or coyotes. This suggests that dire wolves evolved in isolation from the Pleistocene ancestors of these species. Our results also support an early New World origin of dire wolves, while the ancestors of grey wolves, coyotes and dholes evolved in Eurasia and colonized North America only relatively recently

The bii4africa dataset of faunal and floral population intactness estimates across Africa’s major land uses

Sub-Saharan Africa is under-represented in global biodiversity datasets, particularly regarding the impact of land use on species’ population abundances. Drawing on recent advances in expert elicitation to ensure data consistency, 200 experts were convened using a modified-Delphi process to estimate ‘intactness scores’: the remaining proportion of an ‘intact’ reference population of a species group in a particular land use, on a scale from 0 (no remaining individuals) to 1 (same abundance as the reference) and, in rare cases, to 2 (populations that thrive in human-modified landscapes). The resulting bii4africa dataset contains intactness scores representing terrestrial vertebrates (tetrapods: ±5,400 amphibians, reptiles, birds, mammals) and vascular plants (±45,000 forbs, graminoids, trees, shrubs) in sub-Saharan Africa across the region’s major land uses (urban, cropland, rangeland, plantation, protected, etc.) and intensities (e.g., large-scale vs smallholder cropland). This dataset was co-produced as part of the Biodiversity Intactness Index for Africa Project. Additional uses include assessing ecosystem condition; rectifying geographic/ taxonomic biases in global biodiversity indicators and maps; and informing the Red List of Ecosystems

Caractérisation et sources de variation du métabolome : le cas de l’algue brune Lobophora des écosystèmes coralliens de Nouvelle-Calédonie

Marine macroalgae represent a rich source of compounds, also known as specialized metabolites that play diverse ecological functions and are part of adaptive traits. Their concentration can vary according to biotic and abiotic factors but just a few studies on the overall responses of metabolites (metabolome) are available. In this context, the present doctoral study focuses on the potential sources of metabolomic variations in a common coral reef‘s brown alga, Lobophora. To this end, four Lobophora species with various morphologies and habitats have been selected within the New Caledonian lagoon. We first sought to characterize and identify metabolites via traditional chemical approaches. Lobophorenols, previously identified in L. rosacea, were found in this species as well as polyolefin molecules in all studied species. Several bioactivity tests on various biological targets have been set up on algal fractions in a valorization goal and positive results were obtained during antibacterial screening against Staphylococcus aureus. In a second step, the sources of metabolomic variations were studied at several scales by non-targeted metabolomics approaches. These various studies showed that the metabolome of Lobophora is highly variable. The species have their own metabolomic fingerprinting, without intra-thallus variation. Their metabolome varies spatially, depending on the study sites and tested habitats, and over time in relation to environmental factors, such as temperature and salinity. In addition, low pH conditions also lead to metabolomic changes, both in natural conditions (Bouraké site) and under controlled conditions. Among the chemomarkers linked to these changing conditions, we identified lobophorenols as well as several of their potential derivatives, some oxygenated polyunsaturated fatty acid derivatives and polyolefin compounds. Although metabolomics has been successfully applied to discriminate species or to detect the effect of environmental stress, the present work also highlighted the difficulty of working on Lobophora genus, rich in fats and pigments, and the limitation in markers annotation due to the lack of available references for this group of marine organisms still under-researched using this approach.Les macroalgues marines constituent un riche réservoir de composés, aussi appelés métabolites spécialisés, qui jouent diverses fonctions écologiques et font partie des traits adaptatifs. Leur concentration peut varier en fonction de facteurs biotiques et abiotiques mais peu d’études sur les réponses globales des métabolites (métabolome) sont disponibles. C’est dans ce contexte que s’inscrit cette étude doctorale centrée sur les sources potentielles de variations du métabolome chez une algue brune commune des récifs coralliens, Lobophora. Pour cela, quatre espèces de Lobophora présentant des morphologies et des habitats variés ont été sélectionnées dans le lagon de Nouvelle-Calédonie. Nous avons dans un premier temps cherché à caractériser et identifier des métabolites via des approches de chimie traditionnelle. Les lobophorénols, précédemment identifiés chez L. rosacea, ont été retrouvés chez cette espèce ainsi que des molécules polyoléfines chez toutes les espèces étudiées. Plusieurs tests de bioactivité sur diverses souches biologiques ont été mis en place sur des fractions algales dans une visée de valorisation et des résultats positifs ont été obtenus lors du criblage antibactérien contre Staphylococcus aureus. Dans un deuxième temps, les sources de variations du métabolome ont été étudiées à plusieurs échelles par des approches de métabolomique non ciblée. Il ressort de ces diverses études que le métabolome de Lobophora est hyper-variable. Les espèces présentent une empreinte métabolomique propre, sans variation intra-thalle. Leur métabolome varie à l’échelle spatiale, en fonction des sites d’étude et des habitats testés, et au cours du temps en lien avec les facteurs environnementaux, tels que température et salinité. En outre, des conditions de faible pH entraînent également des changements métabolomiques comme nous avons pu le tester en conditions naturelles (site de Bouraké) et en conditions contrôlées. Parmi les marqueurs chimiques liés à ces conditions changeantes nous avons identifié les lobophorénols et plusieurs de leurs potentiels dérivés, des dérivés d’acides gras oxygénés polyinsaturés et des composés polyoléfines. Bien que la métabolomique ait été appliquée avec succès pour discriminer les espèces ou détecter l’effet d’un stress environnemental, les présents travaux ont également souligné la difficulté à travailler sur le genre Lobophora, riche en graisses et pigments, et la limitation dans l’annotation des marqueurs en raison du peu de références disponibles pour ce groupe d’organismes marins encore peu étudiés via cette approche

Characterization and sources of variation of the metabolome : the case of the brown macroalgae Lobophora in New Caledonian coral reefs

Les macroalgues marines constituent un riche réservoir de composés, aussi appelés métabolites spécialisés, qui jouent diverses fonctions écologiques et font partie des traits adaptatifs. Leur concentration peut varier en fonction de facteurs biotiques et abiotiques mais peu d’études sur les réponses globales des métabolites (métabolome) sont disponibles. C’est dans ce contexte que s’inscrit cette étude doctorale centrée sur les sources potentielles de variations du métabolome chez une algue brune commune des récifs coralliens, Lobophora. Pour cela, quatre espèces de Lobophora présentant des morphologies et des habitats variés ont été sélectionnées dans le lagon de Nouvelle-Calédonie. Nous avons dans un premier temps cherché à caractériser et identifier des métabolites via des approches de chimie traditionnelle. Les lobophorénols, précédemment identifiés chez L. rosacea, ont été retrouvés chez cette espèce ainsi que des molécules polyoléfines chez toutes les espèces étudiées. Plusieurs tests de bioactivité sur diverses souches biologiques ont été mis en place sur des fractions algales dans une visée de valorisation et des résultats positifs ont été obtenus lors du criblage antibactérien contre Staphylococcus aureus. Dans un deuxième temps, les sources de variations du métabolome ont été étudiées à plusieurs échelles par des approches de métabolomique non ciblée. Il ressort de ces diverses études que le métabolome de Lobophora est hyper-variable. Les espèces présentent une empreinte métabolomique propre, sans variation intra-thalle. Leur métabolome varie à l’échelle spatiale, en fonction des sites d’étude et des habitats testés, et au cours du temps en lien avec les facteurs environnementaux, tels que température et salinité. En outre, des conditions de faible pH entraînent également des changements métabolomiques comme nous avons pu le tester en conditions naturelles (site de Bouraké) et en conditions contrôlées. Parmi les marqueurs chimiques liés à ces conditions changeantes nous avons identifié les lobophorénols et plusieurs de leurs potentiels dérivés, des dérivés d’acides gras oxygénés polyinsaturés et des composés polyoléfines. Bien que la métabolomique ait été appliquée avec succès pour discriminer les espèces ou détecter l’effet d’un stress environnemental, les présents travaux ont également souligné la difficulté à travailler sur le genre Lobophora, riche en graisses et pigments, et la limitation dans l’annotation des marqueurs en raison du peu de références disponibles pour ce groupe d’organismes marins encore peu étudiés via cette approche.Marine macroalgae represent a rich source of compounds, also known as specialized metabolites that play diverse ecological functions and are part of adaptive traits. Their concentration can vary according to biotic and abiotic factors but just a few studies on the overall responses of metabolites (metabolome) are available. In this context, the present doctoral study focuses on the potential sources of metabolomic variations in a common coral reef‘s brown alga, Lobophora. To this end, four Lobophora species with various morphologies and habitats have been selected within the New Caledonian lagoon. We first sought to characterize and identify metabolites via traditional chemical approaches. Lobophorenols, previously identified in L. rosacea, were found in this species as well as polyolefin molecules in all studied species. Several bioactivity tests on various biological targets have been set up on algal fractions in a valorization goal and positive results were obtained during antibacterial screening against Staphylococcus aureus. In a second step, the sources of metabolomic variations were studied at several scales by non-targeted metabolomics approaches. These various studies showed that the metabolome of Lobophora is highly variable. The species have their own metabolomic fingerprinting, without intra-thallus variation. Their metabolome varies spatially, depending on the study sites and tested habitats, and over time in relation to environmental factors, such as temperature and salinity. In addition, low pH conditions also lead to metabolomic changes, both in natural conditions (Bouraké site) and under controlled conditions. Among the chemomarkers linked to these changing conditions, we identified lobophorenols as well as several of their potential derivatives, some oxygenated polyunsaturated fatty acid derivatives and polyolefin compounds. Although metabolomics has been successfully applied to discriminate species or to detect the effect of environmental stress, the present work also highlighted the difficulty of working on Lobophora genus, rich in fats and pigments, and the limitation in markers annotation due to the lack of available references for this group of marine organisms still under-researched using this approach

An Untargeted Metabolomic Approach for Microphytobenthic Biofilms in Intertidal Mudflats

International audienceMicrophytobenthic (MPB) biofilms in intertidal muddy sediments play important ecological functions in coastal ecosystems. These biofilms are mainly composed of epipelic diatoms but also prokaryotes, with a dominance of bacteria, which excrete diverse extracellular polymeric substances (EPS) according to their environment. While numerous studies have investigated the main components of these EPS matrices via traditional colorimetric assays, their fine composition, notably in specialized metabolites, is still largely unknown. A better chemical characterization of these MPB biofilms is necessary, especially regarding the numerous functions their chemical components play for microorganisms (e.g., motility, cell protection, defense mechanisms, and chemical communication), but also for coastal systems (e.g., primary production, sediment stabilization, larval settlement of some invertebrates with high economical value). An alternative approach to traditional analyses is the use of untargeted metabolomic techniques, which have not yet been applied to such MPB biofilms. The objectives of the present study were to (a) propose a protocol for metabolic fingerprinting by LC-MS and GC-MS for metabolites analysis in polar and non-polar fractions in MPB biofilms extracted from mudflat sediment and to (b) apply this protocol to a case study: the effect of light exposure on the metabolomic fingerprint of the MPB biofilm community. We compared three extraction methods using different mixes of solvents and selected a methanol/chloroform mix (1:1), which gave better results for both techniques and fractions. We then applied the selected protocol to our case study using a short-term light exposure experiment in aquaria (7 days). The present study is the first using a detailed untargeted metabolomic approach on MPB biofilms from mudflat sediment and will provide a solid baseline for further work in this area

Decision-making tools for healthcare structures in times of pandemic

International audienc