Articles publicats en revistes (Institut de Recerca de la Biodiversitat (IRBio))

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Postharvesting population dynamics of the South American sea lion (Otaria byronia) in the southwestern Atlantic
(Wiley, 2015-07-01) Franco-Trecu, Valentina; Drago, Massimiliano; Baladán, Claudia; Garcia-Olazabal, Mateo D.; Crespo, Enrique A.; Cardona Pascual, Luis; Inchausti, Pablo
Many pinniped populations precipitously declined during the 19th and 20th centuries due to overharvesting. In Uruguay, the South American sea lion (SASL) was harvested until 1986. Birth rates in two nearby breeding colonies have had opposite trends for at least 20 yr. We assessed different mechanisms that could explain opposite trends in birth rates in the two SASL colonies. We compared feeding habits (δ15N and δ13C) of breeding females, birth mass, individual growth rate and early survival of pups and the social structure between colonies. Breeding females from the two colonies did not differ in their feeding habits. However, male and female pups grew faster but had a lower survival in the second month in the smallest colony. We found differences in the social structures, with a higher proportion of males in the smallest colony. The latter is important because peripheral SASL males may abduct and kill pups, which may explain the lower survival of pups in smaller colonies. We believe that the cumulative effects of population extractions have lowered the local SASL population size and disrupted its social structure to the point where Allee-like effects could become important and hamper the recovery of the Uruguayan SASL population.
Diet-to-female and female-to-pup isotopic discrimination in South American sea lions
(Wiley, 2015-08-30) Drago, Massimiliano; Franco-Trecu, Valentina; Cardona Pascual, Luis; Inchausti, Pablo
Rationale: The use of accurate, species-specific diet-tissue discrimination factors is a critical requirement when applying stable isotope mixing models to predict consumer diet composition. Thus, diet-to-female and female-to-pup isotopic discrimination factors in several tissues for both captive and wild South American sea lions were estimated to provide appropriate values for quantifying feeding preferences at different timescales in the wild populations of this species. Methods: Stable carbon and nitrogen isotope ratios in the blood components of two female-pup pairs and females' prey muscle from captive individuals were determined by elemental analyzer/isotope ratio mass spectrometry (EA/IRMS) to calculate the respective isotopic discrimination factors. The same analysis was carried out in both blood components, and skin and hair tissues for eight female-pup pairs from wild individuals. Results: Mean diet-to-female Δ13C and Δ15N values were higher than the female-to-pup ones. Pup tissues were more 15N-enriched than their mothers but 13C-depleted in serum and plasma tissues. In most of the tissue comparisons, we found differences in both Δ15N and Δ13C values, supporting tissue-specific discrimination. We found no differences between captive and wild female-to-pup discrimination factors either in Δ13C or Δ15N values of blood components. Conclusions: Only the stable isotope ratios in pup blood are good proxies of the individual lactating females. Thus, we suggest that blood components are more appropriate to quantify the feeding habits of wild individuals of this species. Furthermore, because female-to-pup discrimination factors for blood components did not differ between captive and wild individuals, we suggest that results for captive experiments can be extrapolated to wild South American sea lion populations.
Use of epidermis for the monitoring of tissular trace elements in Mediterranean striped dolphins (Stenella coeruleoalba)
(Elsevier Ltd., 2015-03-01) Borrell Thió, Assumpció; Clusa Ferrand, Marcel; Aguilar, Àlex; Drago, Massimiliano
Trace elements accumulate in epidermis, liver, kidney and muscle tissues in cetaceans. However, contrarily to internal tissues, epidermis can be sampled using minimally-invasive techniques. We investigate the patterns of trace element tissue concentrations in relation to individual sex and length and the degree of inter-tissue equilibrium between epidermis and the main internal organs of the Mediterranean striped dolphin. With it, we aim to test whether epidermis is a suitable tissue to predict trace element concentrations of internal tissues in cetaceans. We focused on trace elements with high potential toxicity (mercury and cadmium) or biological significance (zinc, copper and selenium). In contrast to what was found for Cu and Zn, the concentrations of Hg, Cd and Se in epidermis were positively correlated with the levels found in the internal tissues sampled probably due to their capacity to bioaccumulate. Thus, we conclude that sampling and analysing epidermis is appropriate to monitor and predict the concentrations of Hg, Cd and Se in internal tissues but not for Cu and Zn.
Concentrations of mercury in tissues of striped dolphins suggest decline of pollution in Mediterranean open waters
(Elsevier Ltd., 2014-07-01) Borrell Thió, Assumpció; Aguilar, Àlex; Tornero Álvarez, Ma. Victoria; Drago, Massimiliano
The Mediterranean is a semi-enclosed sea subject to high mercury (Hg) pollution from both natural and anthropogenic sources. With the objective of discerning temporal changes in marine Hg pollution in the oceanic waters of the northwestern Mediterranean Sea, we analysed liver and kidney from striped dolphins (Stenella coeruleoalba) collected during 2007–2009 and compared them with previous results from a similar sample from 1990–1993. The effect of body length and sex on tissue Hg concentrations was investigated to ensure an unbiased comparison between the periods. The Hg concentrations did not show significant sex-related differences in any tissue or period but were correlated positively with body length. Using body length as a covariate, Hg concentrations in liver and kidney were higher in 1990–1993 than in 2007–2009. This result suggests that measures to reduce emissions in Western European countries have been effective in reducing mercury pollution in Mediterranean open waters.
Dietary consistency of male South American sea lions (Otaria flavescens) in southern Brazil during three decades inferred from stable isotope analysis
(Springer Verlag, 2015-02-01) Zenteno Devaud, Lisette; Crespo, Enrique A.; Vales, Damián G.; Silva, Laura Alejandra; Saporiti, Fabiana; De Oliveira, Larissa Rosa; Secchi, Eduardo R.; Drago, Massimiliano; Aguilar, Àlex; Cardona Pascual, Luis
Marine predators may undergo remarkable dietary changes through time as a result of both anthropogenic and natural changes in the environment, but this variability is often difficult to tackle and seldom incorporated into ecosystem models. This paper uses the stable isotope ratios of carbon and nitrogen in skeletal material of South American sea lions from Brazilian scientific collections to investigate whether these animals modified their diet from 1986 to 2009, as reported for other marine predators in the region. Stable isotope ratios indicated that demersal potential prey were always enriched in 13C as compared with pelagic prey. Accordingly, the absence of any statistically significant correlation between stranding year and the δ13C values of adult males indicated no major increase in the consumption of pelagic prey from 1986 to 2009. Likewise, the results of the mixing model SIAR revealed a mixed diet including pelagic and demersal prey, with a central role for demersal fishes throughout the whole period. Furthermore, SIAR suggested no major changes in the proportion of pelagic and demersal prey in the diet of adult male South American sea lions during the past three decades. Demersal fishes were also relevant prey for juvenile South American sea lions during the whole period, but they always consumed a larger proportion of pelagic prey than the adults did. These results suggest no major changes in the diet of male South American sea lions during the past three decades in southern Brazil, contrary to what has been reported for other to predators in the regions and for the species in northern Patagonia.
Prey dynamics and breeding performance in a generalist predator: the differential role of prey densitiy, biomass, and effective consumption rates
(Elsevier Masson SAS, 2024-05-01) Torre, Ignasi; Grajera, Joan; Amat Orriols, Fèlix; Oro, Daniel; Mañosa, Santi
The breeding performance of predators is influenced by the differential consequences of prey density, prey biomass and effective consumption rates. Using camera traps at nests, we investigated whether changes in prey abundances caused functional and/or numerical responses of the common buzzard (Buteo) in a Mediterranean woodland region. After determining 1150 prey delivered to the nests by adults, we found that the biomass of prey caught was not a good indicator of its influence on individual life history traits such as productivity. Indeed, the consumption of small mammal prey, despite representing only 11% of the biomass delivered, had a much greater influence on buzzards' productivity than the consumption of snakes, which made up 47% of the biomass delivered. Live trapping evidenced that small mammals were roughly preyed according to its availability in the field, and their abundance in spring was directly related to buzzards' productivity and inversely related to hatching dates. Small mammals – mostly mice – can be considered as very suitable prey, owing quick handling times, profitability, and high energy intake. Our results pointed out the relevance of mice on buzzards' breeding performance, and altogether with the outstanding role of open-land small mammals on buzzards' demography during autumn-winter, suggested a key role of small mammals on buzzards’ ecology throughout the year cycle in the Mediterranean area studied. These findings have important implications for our understanding of the foraging strategies of generalist species and the role that habitat and environmental factors play in shaping them.
Effects of niche marginality on hotter-drought tree mortality in angiosperms and gymnosperms
(John Wiley & Sons, 2025-09-21) Batllori Presas, Enric; Hammond, William M.; Jump, Alistair; Pérez-Navarro, María Ángeles; Allen, Craig D.; Lloret Maya, Francisco
Aim: Current observations of global tree mortality events associated with drought raise concerns about climate change risks to forests' dynamics and function. It is unclear which forests are more susceptible to pulses of mortality under further changing climates. We examined whether tree mortality related to hotter droughts is predominantly occurring in edge or core populations in niche space and assessed whether mortality patterns are consistent with species' drought tolerances. Location: Global. Time Period: 1970–2020. Major Taxa Studied: Angiosperm and gymnosperm trees. Methods: We estimated species' climatic niches on the basis of global occurrences and annual time series of climate. We computed the distance to the niche core of drought mortality sites (982 observations, 44 tree species) and compared it with null models of randomly distributed tree mortality. We assessed how loss of xylem conductance and hydraulic safety margin related to populations' position in niche space and to the degree of climate anomaly during mortality. Results: In the year of mortality, 64.3% of the sites were closer to the species' niche edge than the niche core. However, when considering long-term climate averages, both marginal and central populations experienced drought-associated pulses of mortality. Overall, tree mortality was related to populations' shifts towards the edge of species' climatic niches and, in angiosperm mortality sites, species' drought tolerances were correlated with the intensity of climatic anomalies. In gymnosperm sites, marginal populations were more affected and other processes, such as heat-induced stress or cumulative drought effects, may have affected mortality. Main Conclusions: Both marginal and central populations, even for highly drought-tolerant species, are vulnerable to climate change. Climate anomaly magnitude, cumulative drought effects, plant physiological limits and species niche geometry help explain range-wide patterns of hotter-drought-associated tree mortality.
Molecular evidence for the intermediate disturbance hypothesis in an acidified marine system
(Springer Verlag, 2025-10-01) González-Delgado, Sara; Pérez Portela, Rocío; Hernández, José Carlos
The Intermediate Disturbance Hypothesis (IDH), postulated by Connell (1978), suggests that ecosystems exhibit higher species diversity when disturbances occur at intermediate scales. In this study, the applicability of the IDH at the intraspecific scales (organismal) was investigated using molecular data. As an experimental perturbation framework, a naturally acidified system located in La Palma Island, Canary Island (Spain) with a sharp fluctuating pH gradient was sampled. Molecular data were obtained from sequences of a fragment of the mitochondrial Cytochrome C Oxidase subunit I gene in two sea urchin species (Arbacia lixula and Paracentrotus lividus) to explore genetic diversity at the organism level. These data were compared with previous metabarcoding results of taxonomic benthic diversity at the community level. Both sea urchin species showed the highest levels of haplotype and nucleotide diversity at the intermediate pH fluctuation zone, mirroring metabarcoding data that revealed the highest levels of taxonomic diversity at the same zone. The results support the validity of the IDH in marine ecosystems affected by strong pH fluctuations and across different levels of biological organization (from organisms to communities).
The role of fire in terrestrial vertebrate richness patterns
(John Wiley & Sons, 2023-04-01) Moritz, Max A.; Batllori Presas, Enric; Bolker, Benjamin M.
Productivity is strongly associated with terrestrial species richness patterns, although the mechanisms underpinning such patterns have long been debated. Despite considerable consumption of primary productivity by fire, its influence on global diversity has received relatively little study. Here we examine the sensitivity of terrestrial vertebrate biodiversity (amphibians, birds, and mammals) to fire, while accounting for other drivers. We analyze global data on terrestrial vertebrate richness, net primary productivity, fire occurrence (fraction of productivity consumed), and additional influences unrelated to productivity (i.e., historical phylogenetic and area effects) on species richness. For birds fire is associated with higher diversity, rivaling the effects of productivity on richness, and for mammals fire’s positive association with diversity is even stronger than productivity; for amphibians, in contrast, there are few clear associations. Our findings suggest an underappreciated role for fire in the generation of animal species richness and the conservation of global biodiversity.
Chlorination Cessation Alters Greenhouse Gas Dynamics in Artificial Urban Ponds
(Wiley, 2025-08-05) Montes-Pérez, Jorge Juan; Irusta, Paula; Cañas, Lídia; Mejía, Fernanda; Pinaud-Brageot, Näel; Obrador Sala, Biel; Puigserver Cuerda, Diana; Millán Martos, Alberto; Schiller Calle, Daniel von
Cities are facing an ecological challenge, and international policies are increasingly focused on implementing nature-based solutions to support this transition. In this context, the naturalization of artificial urban ponds (AUP) is a promising approach with proved benefits for biodiversity and human well-being. However, the naturalization of AUP may be accompanied by increased greenhouse gas (GHG) emissions. Here, we evaluated the effect of chlorination cessation, an essential step in the naturalization process, on GHG dynamics in AUP. Partial pressures of CO2 (pCO2), CH4 (pCH4), and N2O (pN2O) were measured in 41 artificial urban ponds (28 non-chlorinated and 13 chlorinated) in the city of Barcelona during winter and summer to assess: (a) the effect of chlorination treatment, (b) the effect of seasonality, and (c) the main drivers behind the partial pressures of these GHGs. Results show that although chlorination cessation increased pCH4, it reduced pN2O and had no significant effect on pCO2. The main drivers of these patterns were naturalization, with factors related to primary production playing a major role; seasonality, with temperature as a key environmental variable; and groundwater legacy. Importantly, the net global warming potential (GWP), expressed as CO2 equivalents, was not significantly higher in non-chlorinated ponds. These findings suggest that the naturalization of artificial water bodies could be a viable strategy to create more resilient cities without significantly increasing GHG emissions.
Learning the syntax of plant assemblages
(2025-10-13) Leblanc, César; Bonnet, Pierre; Servajean, Maximilien; Thuiller, Wilfried; Chytrý, Milan; Aćić, Svetlana; Argagnon, Olivier; Biurrun, Idoia; Bonari, Gianmaria; Bruelheide, Helge; Campos, Juan Antonio; Čarni, Andraž; Ćušterevska, Renata; De Sanctis, Michele; Dengler, Jürgen; Dziuba, Tetiana; Garbolino, Emmanuel; Jandt, Ute; Jansen, Florian; Lenoir, Jonathan; Moeslund, Jesper Erenskjold; Pérez Haase, Aaron; Pielech, Remigiusz; Sibik, Jozef; Stančić, Zvjezdana; Uogintas, Domas; Wohlgemuth, Thomas; Joly, Alexis
To address the urgent biodiversity crisis, it is crucial to understand the nature of plant assemblages. The distribution of plant species is shaped not only by their broad environmental requirements but also by micro-environmental conditions, dispersal limitations, and direct and indirect species interactions. While predicting species composition and habitat type is essential for conservation and restoration purposes, it remains challenging. In this study, we propose an approach inspired by advances in large language models to learn the ‘syntax’ of abundance-ordered plant species sequences in communities. Our method, which captures latent associations between species across diverse ecosystems, can be fine-tuned for diverse tasks. In particular, we show that our methodology is able to outperform other approaches to (1) predict species that might occur in an assemblage given the other listed species, despite being originally missing in the species list (16.53% higher accuracy in retrieving a plant species removed from an assemblage than co-occurrence matrices and 6.56% higher than neural networks), and (2) classify habitat types from species assemblages (5.54% higher accuracy in assigning a habitat type to an assemblage than expert system classifiers and 1.14% higher than tabular deep learning). The proposed application has a vocabulary that covers over 10,000 plant species from Europe and adjacent countries and provides a powerful methodology for improving biodiversity mapping, restoration and conservation biology. As ecologists begin to explore the use of artificial intelligence, such approaches open opportunities for rethinking how we model, monitor and understand nature.
Annual Vegetation of Saline Seasonal Wetlands (Crypsietea aculeatae) in Europe
(Wiley, 2025-11-07) Iemelianova, Svitlana; Dítě, Daniel; Dítě, Zuzana; Willner, Wolfgang; Bergmeier, Erwin; Pérez Haase, Aaron; Dziuba, Tetiana; Aćić, Svetlana; Ćuk, Mirjana; Ćušterevska, Renata; Dubyna, Dmytro; Vassilev, Kiril; Chytrý, Milan
Aims: The class Crypsietea aculeatae comprises pioneer ephemeral dwarf-graminoid vegetation occurring in periodically flooded saline habitats. Although numerous regional studies have described this vegetation, a unified classification across Europe has been lacking. This study aims to establish a formalized, continent-wide classification at the association level, identify its biogeographical patterns, and assess relationships between species composition and environmental gradients. Location: Europe (except Armenia, Azerbaijan, Georgia, and Russia). Methods: We compiled a dataset of 2538 vegetation plots from the European Vegetation Archive (EVA), private databases, and literature. A hierarchical expert system was developed using formal definitions of syntaxa based on species cover. Nonmetric multidimensional scaling (NMDS) was applied to evaluate compositional differences and reveal biogeographical patterns. Distance-based redundancy analysis (db-RDA) and unweighted community means of Ellenberg-type indicator values (EIVs) were used to assess environmental drivers. Results: We present a revised syntaxonomic framework for the class Crypsietea aculeatae and propose updates to the EuroVegChecklist. One alliance (Cypero-Spergularion marinae) and four associations (Crypsietum aculeatae, Crypsietum schoenoidis, Cyperetum pannonici, and Oxybasio chenopodioidis-Crypsietum aculeatae) were formally defined, with basic descriptions of their species composition, ecological characteristics, and geographical distribution. The main gradients in vegetation variability within the class Crypsietea aculeatae are driven by climatic gradient and edaphic factors, including soil moisture, soil acidity, salinity, and nutrient availability. Conclusions: We established the first formal classification of annual vegetation in European saline seasonal wetlands. The syntaxonomic nomenclature was revised, and modifications to the EuroVegChecklist were proposed. The resulting classification system, accompanied by an expert system, enables consistent application in nature conservation and ecological research.
Crossing the polar front—Antarctic species discovery in the nudibranch genus Tritoniella (Gastropoda)
(Springer Verlag, 2022-06-01) Schächinger, Peter M.; Schrödl, Michael; Wilson, Nerida G.; Moles, Juan
Tritoniella belli is the only valid species of a nudibranch genus endemic to the Southern Ocean. Recent exhaustive sampling and molecular analyses led to the discovery of several new lineages. A total of 69 specimens were collected from 25 sites across the Weddell and Scotia Seas, from 5 to 751 m depth. In this study, we provide morphological and anatomical characters to describe five new Tritoniella species, namely T. gnocchi n. sp., T. prinzess n. sp., T. gnathodentata n. sp., T. schoriesi n. sp., T. heideae n. sp. Detailed descriptions of colouration, external morphology, digestive and reproductive organs, distribution, and ecology are presented in a systematic context. These are compared to the type material from the Ross Sea of T. belli and its synonym T. sinuata, whose status requires additional sampling to be solved. Discrete differences in external characters, including the shape of dorsal notum ridge and mantle edges, support the species hypotheses delimited by Moles, Berning et al. (2021). Moreover, detailed scanning electron microscopy images of the masticatory border of the jaws, radula teeth, and penial papilla were provided and their differences discussed. The gut content of all species revealed sclerites of Primnoidae gorgonians as their preferred prey. Pseudo-cryptic radiations along the Scotia Arc, explained by the combination of distribution reduction due to glacial cycles and the existence of refugia, and enhanced by their direct development, could explain the allopatric speciation events in Tritoniella species.
Analysing the contribution of intermittent rivers to beta diversity can improve freshwater conservation in Mediterranean rivers
(Springer Verlag, 2024-04-25) Soria Extremera, Maria; Bonada i Caparrós, Núria; Cid Puey, Núria; Ortega, Jean Carlo Gonçalves; Bini, Luis Mauricio; Acosta Rivas, Carlos Raul; Gutiérrez-Cánovas, Cayetano; Rodríguez Lozano, Pablo; Fortuño, Pau; Vinyoles Cartanyà, Dolors; Gallart Gallego, Francesc; Prat i Fornells, Narcís
In Mediterranean climate regions, intermittent rivers (IRs) harbor highly dynamic communities with species and trait composition changing over time and space. Simultaneously considering multiple biodiversity facets and a spatiotemporal perspective is, therefore, key to developing effective conservation strategies for these ecosystems. We studied the spatiotemporal dynamics of aquatic macroinvertebrates in rivers of the western Mediterranean Basin by analysing (1) the taxonomic and functional richness and the local contribution to beta diversity (LCBD; measured considering taxonomic and functional facets) of perennial rivers and IRs over five sampling times, and (2) their relation with flow intermittence, local environmental uniqueness, and the number of anthropogenic impacts. Both analyses were also conducted for the subset of data including only IRs to compare values between their flowing and disconnected pool phases. According to our results, taxonomic and functional richness tended to be higher in perennial rivers than in IRs, while taxonomic and functional LCBD tended to be higher in IRs than in perennial rivers. When comparing IR sites over time, higher values of taxonomic and functional LCBD corresponded mostly to their disconnected pool phase. Flow intermittence, the number of anthropogenic impacts and th environmental uniqueness were significant predictors of taxonomic and functional richness, but only flow intermittence was an important predictor of taxonomic LCBD. For the IR-only data subset, disconnected pool permanence was the main predictor explaining spatiotemporal patterns. Our results highlight the importance of IRs to biodiversity conservation of Mediterranean climate rivers, especially during the disconnected pool phase, suggesting that these ecosystems cannot be ignored in conservation planning strategies.
Restoring High Mountain Sphagnum Communities in the Central Pyrenees
(MDPI, 2025-10-07) Pladevall Izard, Eulàlia; Pérez Haase, Aaron; Carrillo, Empar; Escolà Lamora, Nil; Ninot i Sugrañes, Josep Maria
A handful of Sphagnum species and their ecosystems find their southernmost occurrence in the Pyrenees, and these small, relict units are endangered through anthropic activities and climatic change. A number of hydropower reservoirs covered former mire systems with water or let them ashore. These infrastructures will eventually become useless and abandoned, and the mires could possibly be restored, but there have been no known experiments in the Pyrenees in this field. The removal of the dam of a small reservoir in the Central Pyrenees in 2012 uncovered bare ground that was appropriate for testing mire restoration. In 2017, we started the restoration of two Habitats of Community Interest (HCIs), i.e., transition mires and quaking bogs (HCI 7140) and active raised bogs (HCI 7110*). To restore HCI 7140, we set a Carex rostrata population by planting cuttings and then small tufts of two Sphagnum species within the sedge sward. In parallel, we set small clumps of two other Sphagnum species intended to grow into hummocks (HCI 7110*). After seven growing seasons, HCI 7140 reached a good progression level, with a prosperous C. rostrata sward and progressive expansion of the Sphagnum populations. HCI 7110* turfs had varying performance, exhibiting moderate survivorship and positive expansion of the remaining turfs. The varying performance of the restored populations illustrates the possibilities of restoring mire communities in suboptimal environments. Interestingly, such restorative actions are appropriate for enhancing populations of species under threat, such as Sphagnum divinum.
Tracking Soil Organic Carbon and Nitrogen under Organic Management: A Temporal Perspective
(MDPI, 2025-10-11) Bragg, Daniel; Romanyà i Socoró, Joan; Blanco Moreno, José Manuel; Sans, Xavier (Sans i Serra)
Understanding the long-term impact of agricultural practices on soil parameters is essential for improving soil quality and sustainability. Soil Organic Carbon (SOC) and total Nitrogen (N) are key indicators due to their influence on crop productivity, nutrient cycling, and microbial activity. This study assesses the effects of tillage intensity (inversion vs. non-inversion) and organic amendments (manure vs. no manure) on SOC and total N dynamics in Mediterranean rain-fed arable systems. Data were collected over a ten-year field trial (2011–2020) in Catalonia, under cereal–legume rotation and organic management, focusing on two soil depths (0–10 and 10–20 cm). Fertilization was the main driver of SOC and N changes. Non-inversion tillage promoted topsoil accumulation and microbial colonization, especially during the first period (2011–2015). The combination of manure and reduced tillage led to faster and greater SOC increases. Moreover, initial SOC levels were negatively related to SOC changes in the topsoil. These results revealed the combination of manure and non-inversion tillage as the more suitable management practice to preserve soil quality in organic arable rain-fed systems, emphasizing the importance of understanding the impact of agricultural management in the long-term under Mediterranean conditions.
Drivers of Alpine Mire Vegetation at Their Range Limit
(MDPI, 2025-10-08) Pérez Haase, Aaron; Ninot i Sugrañes, Josep Maria
Mires are fragile ecosystems in which plant communities are structured by complex interactions among hydrological regimes and groundwater properties. Although extensively studied in boreal and temperate regions, their environmental drivers in southern European mountains remain poorly understood. We investigated five complex mires in the Pyrenees, sampling 156 plots of vascular plants and bryophytes while measuring water table dynamics and groundwater chemistry over two years. Vegetation was classified into six main groups, including acid and alkaline fens, transition mires and Sphagnum hummocks. Ordination analyses (tb-PCA and RDA) revealed that mean water table depth, groundwater calcium and silicon content, and pH were the most important determinants of floristic composition. Bryophytes responded primarily to pH, whereas vascular plants were more influenced by water table variables, reflecting functional trait differences. Despite these environmental effects, spatial structure explained a comparable or greater proportion of variance, especially for vascular plants, underscoring the roles of local species pools, dispersal limitation, and site history in shaping community patterns. Establishing a reliable baseline is crucial for interpreting the distribution patterns of mire vegetation. Our results demonstrate that both environmental gradients and spatial processes are fundamental to understanding mire vegetation and highlight the importance of analyzing plant taxonomic groups separately.
Intraindividual variability as a large source of trait variation in clonal tundra dwarf shrubs along elevation and latitude gradients
(John Wiley & Sons, 2025-09-23) Anadon Rosell, Alba; Casanovas, Amanda; Bog, Manuela; Illa Bachs, Estela; Kreyling, Jürgen; Martínez Vilalta, Jordi, 1975-; Ninot i Sugrañes, Josep Maria; Pérez Haase, Aaron; Wilmking, Martin
Aim: Intraindividual trait variability (iITV), which is the variability among repeated architectural units within an individual, may represent a crucial dimension of functional diversity in plant eco-evolutionary dynamics. Although inter- and intraspecific trait variability have been widely studied, the extent of iITV remains largely overlooked. Since iITV might be especially relevant in long-lived clonal plants, we investigated sources of trait variability (species, site, clone, ramet, leaf) in tundra clonal dwarf shrubs, particularly focusing on iITV and its potential drivers. Location: Europe. Time Period: July 2019 to September 2020. Major Taxa Studied: Clonal dwarf shrubs. Methods: We sampled four widespread boreo-alpine clonal dwarf shrub species (Dryas octopetala, Empetrum hermaphroditum, Vaccinium myrtillus and Vaccinium uliginosum) along elevation gradients in the Pyrenees and along a latitude gradient in Europe. At each site, we selected four clones per species and sampled five ramets per clone. We measured size-architectural traits in each ramet and leaf traits in five leaves per ramet. We quantified interspecific, intraspecific and iITV, investigated the relationship between iITV and both climate and clone structural variables, and compared sampling protocols either accounting for or ignoring iITV. Results: Although interspecific trait variability was substantial, we found large proportions of iITV within species. Size-architectural traits showed larger iITV (up to 100% of ITV), but leaf traits also showed remarkable values (up to 77%). Our results showed that iITV increased with mean annual temperature for specific leaf area. However, climate and clone structural variables were not predictive for iITV for any other trait. Conclusions: Our quantification of iITV in clonal dwarf shrubs evidences the importance of this source of variability and its potential ecological implications and emphasises the need to integrate it in sampling protocols, both to avoid bias in comparative studies and improve the predictive capacity of trait-based approaches in population and community ecology.
From marine sand to land and rivers: A combined phylogenomic strategy unveils the evolution of minute Acochlidimorpha slugs (Gastropoda: Heterobranchia)
(Elsevier, 2025-12-01) Fernández-Simón, Jose; Jörger, Katharina M.; Brenzinger, Bastian; Schrödl, Michael; Wilson, Nerida G.; Neusser, Timea P.; Moles, Juan
The repeated colonisation of non-marine environments in panpulmonate molluscs represents a major evolutionary transition, yet many lineages remain poorly understood. Among gastropods, Acochlidimorpha stands out for its ecological and morphological diversity, originating in marine interstitial habitats before independently invading freshwater and terrestrial ecosystems. Here, we present the most complete phylogeny of Acochlidimorpha to date based on a global taxon sampling collected over several decades. We integrate ultra-conserved element (UCE) data from 58 museum-preserved specimens—comprising over 1,700 nuclear loci—with all publicly available Sanger-sequencing markers, totalling more than 150 specimens. This pioneering approach sets a new benchmark for phylogenomic studies in minute molluscan lineages. Our results resolve long-standing systematic ambiguities, reinstating Pontohedylidae stat. rest. and Strubelliidae stat. rest. and establishing Helicohedylidae fam. nov. Within Acochlidioidea, Strubelliidae is recovered as the sister to Pseudunelidae + (Tantulidae + Acochlidiidae). At the species level, we clarify the position of key taxa, including Asperspina loricata and two unidentified species of Hedylopsis. Ancestral habitat reconstruction analyses reveal at least four independent transitions to freshwater and terrestrial environments, highlighting the anatomical innovations facilitating these shifts. Altogether, our study provides a robust evolutionary framework for Acochlidimorpha, offering new insights into the processes underlying terrestrialisation, morphological evolution, and ecological diversification in a lineage characterised by both extreme miniaturisation and evolutionary dynamism.
Skeletal magnesium content in Antarctic echinoderms along a latitudinal gradient
(Elsevier B.V., 2024-11-01) Azcárate-García, Tomás; Ávila Escartín, Conxita; Figuerola Balañá, Blanca
Ocean warming and acidification driven by anthropogenic CO2 emissions may impact the mineral composition of marine calcifiers. Species with high skeletal Mg content could be more susceptible in polar regions due to the increased solubility of CO2 at lower temperatures. We aimed to assess the environmental influence on skeletal Mg content of Antarctic echinoderms belonging to Asteroidea, Ophiuroidea, Echinoidea and Holothuroidea classes, along a latitudinal gradient from the South Shetland Islands to Rothera (Adelaide Island). We found that all skeletal structures, except for echinoid spines, exhibited high Mg content, with asteroids showing the highest levels. Our results suggest that asteroids and holothuroids exert a higher biological capacity to regulate Mg incorporation into their skeletons. In contrast, the variability observed in the skeletal Mg content of ophiuroids and echinoids appears to be more influenced by local environmental conditions. Species-specific differences in how environmental factors affect the skeletal Mg content can thus be expected as a response to global climate change.

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