Articles publicats en revistes (Biologia Evolutiva, Ecologia i Ciències Ambientals)

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Vitamin E protects from lipid peroxidation during winter stress in the seagrass Cymodocea nodosa
(Springer Verlag, 2022-02-01) Munné Bosch, Sergi; Puig i Sardà, Susana; Fenollosa, Erola; Casadesús Cabral, Andrea; Fernández Muñoz, Esteve
Despite low temperatures can adversely affect the proper growth and development of marine angiosperms, by, among other processes, increasing reactive oxygen species production and causing oxidative damage to lipid membranes, the role of vitamin E in seagrasses, such as Cymodocea nodosa has not been explored thus far. Here, we aimed to better understand the possible role of this chain-breaking (peroxyl radical-trapping) antioxidant in response to low temperatures, and most particularly in relation to the occurrence of photo-inhibition and lipid peroxidation. Low temperatures caused an important desiccation of leaves, but not of rhizomes, which were much more tolerant to cold stress than leaves. Cold stress during winter was associated with chlorophyll loss and transient photo-inhibition, as indicated by reversible reductions in the Fv/Fm ratio. Adjustments in pigment antenna size and vitamin E contents per unit of chlorophyll during winter may help protect the photosynthetic apparatus from sustained photo-inhibitory damage and lipid peroxidation events in leaves. Rhizomes also accumulated significant amounts of vitamin E, although to a much lesser extent than leaves, and kept protected from lipid peroxidation during winter, as indicated by malondialdehyde contents, a product from secondary lipid peroxidation. It is concluded that vitamin E can help protect both leaves and rhizomes from lipid peroxidation, although cold stress during winter can cause transient photo-inhibition of the photosynthetic apparatus, in C. nodosa.
Impact of mechanized clam dredging on the discarded megabenthic fauna on the Catalan coast (NW Mediterranean)
(Cambridge University Press (CUP), 2021-06-02) Baeta Alacio, Marc; Rubio, Carolina; Breton, Françoise
There is an important small-scale fishery using mechanized dredges and targeting clams (mainly wedge clam Donax trunculus and striped venus clam Chamelea gallina) along the Catalan coast (NW Mediterranean Sea). This study evaluated for the first time the discards and impact of mechanized clam dredging on the Catalan coast. To this end, three surveys were performed on board standard clam vessels (September and November 2016 and January 2017). Surveys were conducted in the three main clam fishing areas (Rosas Bay, South Barcelona and Ebro Delta). The composition of discards and the impact caused to discarded species was assessed using a three-level scale (undamaged; minor or partial damage; and lethal damage). Our study revealed that a large proportion of the catch (between 67–82% weight) is discarded. Even though about 63% of the discarded species were undamaged, 11% showed minor or partial damage and 26% lethal damage. Infaunal and epifaunal species with soft-body or fragile shells were the most impacted by the fishing activity (e.g. the sea urchin Echinocardium mediterraneum (∼89%) and the bivalve Ensis minor (∼74%)). Our results showed different levels of impact by target species and fishing area.
Assessment of land-based threats to Atlantic pelagic seabirds
(Wiley, 2026-03-17) Kalaitzakis, Ioannis; Rodrigues, Ana S. L.; Dias, Maria P.; Davies, Tammy E.; Baran, Mark A.; Bhola, Nina; Boulinier, Thierry; Bried, Joel; Campioni, Letizia; Ceia, Filipe R.; De Pascalis, Federico; Dehnhard, Nina; Fagundes, Ana Isabel; Gilg, Olivier; González-Solís, Jacob; Grémillet, David; Hernández-Montero, Marcos; Krüger, Lucas; Kuepfer, Amanda; Major, Heather L.; Mallory, Mark L.; Militão, Teresa; Oliveira, Nuno; Oppel, Steffen; Paiva, Vitor H.; Pereira, Jorge M.; Phillips, Richard A.; Pollet, Ingrid L.; Ponchon, Aurore; Raine, André F. ; Ramos i Garcia, Raül; Ramos, Jaime A.; Robertson, Gregory J.; Vicente-Sastre, Diego; Shutler, Dave; Silva, Mónica C.; Wanless, Sarah; Zenatello, Marco; Rouyer, Marie-Morgane
Seabirds are exposed to numerous threats throughout their life-cycles, includingland-based threats during their breeding season such as invasive species,diseases, or light pollution. Here we assess the timing, scope, and severity ofland-based threats to populations of highly mobile petrels, albatrosses, stormpetrels,and alcids in the Atlantic Ocean, to guide priorities for their conservationacross their mostly island-breeding areas. By combining our own fieldexpertise of these species with a literature review, we built a dataset characterizing18 threats for 49 species across 38 Large Marine Ecosystems. We analyzethis dataset by highlighting the most impactful threats and the most impactedregions. Addressing invasive alien species on Tristan da Cunha & Gough andon the islands of the Canary Current are the interventions with the greatestpotential to stimulate seabird population recovery across the Atlantic Ocean.Our results highlight priorities for targeted management actions that can supportseabird conservation.
Assessing the role of habitat, climate, and anthropizationgradients on terrestrial mammal diversity in the western Mediterranean basin
(Wiley, 2024-07-14) Fernández Cabello, Ignasi; Franch, Marc; Vilella, Marc; Fernandez Arrieta, Nerea; Rota, Marc; Sanglas Oliva, Ariadna; Baqué Díaz, Eric; Gallardet, Marc; Federico, Pau; Peris, Albert; Serratosa, Eric; Real, Joan; Sayol, Ferran; Puig-Gironès, Roger
Mammal species globally exhibit distribution patterns conditioned by environmental conditions and human impact. The Mediterranean basin provides an ideal system to study these effects due to its diverse climate, and habitat conditions. In this work, we aim to assess the impact of landscape heterogeneity and anthropization degree on terrestrial mammal diversity in this region. Accordingly, we deployed over 300 camera traps across 28 sites for 3 months. Detected mammal species (weighing more than 1kg) were classified as domestic carnivores, domestic ungulates, wild carnivores, wild ungulates, lagomorphs, and large rodents. Alpha and beta diversity were calculated for each group and all wild mammals. Simple linear regressions and multimodal analysis were conducted between mammal diversities and climate, environmental conditions, landscape heterogeneity, and anthropization degree variables. Redundancy analyses were performed to identify variables and species determining the mammalian community composition. Indexes measuring landscape heterogeneity, anthropization degree, and its 30-year change did not correlate with mammal diversity. However, the difference in elevation within sites and domestic carnivore abundance showed a significant positive correlation with some of the diversity indexes. Nonetheless, rainfall and mean elevation factors generally showed the highest correlation with mammal diversity. Instead, a few influential species, including generalists and open-habitat specialists, highlighted the importance of conserving open areas, as well as the importance of the Pyrenees region as a key habitat for certain species. Therefore, climatic variables emerged as the key determinants of mammal diversity, highlighting climate change as a potential threat to mammal diversity in this area.
From Purpose to Persistence: How Intentional Introductions by Humans Influence Ecological Niches of Non‐Native Plants
(John Wiley & Sons, 2026-05-14) Riera, Marc; Chytrý, Milan; Melero Cavero, Yolanda; Sáez, Llorenç; Attorre, Fabio; Axmanová, Irena; Biurrun, Idoia; Bonari, Gianmaria; Buldrini, Fabrizio; Delbosc, Pauline; Dengler, Jürgen; Jandt, Ute; Jansen, Florian; Jiménez-Alfaro, Borja; Pielech, Remigiusz; Pyšek, Petr; Šibíková, Maria; Pino, Joan
Aim: The intentional or unintentional transport of non-native plants is key to overcoming geographic barriers. However, it remains unclear whether such introduction pathways associate with overcoming environmental barriers, which is key for successful invasion. Here, we test how intentionality of introduction associates with niche breadth and niche harshness. Location: Europe. Time Period: 1914–2020. Major Taxa Studied: 220 plant species. Methods: Across >60,000 invaded vegetation plots, we tested whether intentionality of introduction (intentional, unintentional, or both) and characteristics of non-native plants (native climatic niche breadth, growth form, dispersal syndrome, height, residence time) were associated with their niche breadth, quantified through habitats, climate, and co-occurring flora. We tested how the intentionality of introduction was associated with environmental harshness (drought, salinity, oligotrophy, and elevation), while accounting for land-cover and habitat types. Results: Non-native plants introduced both intentionally and unintentionally had a broader habitat range, compared to nonnative plants introduced only unintentionally. A broad climatic niche in the native range was associated with a broader invaded climatic niche, while a long residence time was associated with broader habitat and biotic niches. Intentional introduction was associated with the invasion of dry habitats and forests, whereas unintentional introduction was linked to the invasion of saline, high-elevation, and disturbed environments. Main Conclusions: In addition to triggering invasions, the type of process responsible for introduction can partly explain how non-native plants overcome environmental barriers in the invaded range. The intentionality of introduction was associated with niche breadth only in terms of habitat range, while the association with niche harshness depended on the type of stress, which highlights the importance of integrative niche assessments. The relationship between intentionality of introduction and the invaded niche could relate to intentionality-specific differences in biological attributes (environmental tolerance, dispersal capacity, and preference for disturbance) and the introduction process (propagule pressure and residence time).
Timing and direction of faunal exchange between the Nearctic and the Palaearctic in Odonata
(John Wiley & Sons, 2024-05-31) Pàmies‐Harder, Maria; Múrria i Farnós, Cesc; Abbott, John C.; Abbott, Kendra; Kalkman, Vincent J.
Aim Species have different distribution patterns across the globe and among biogeographical regions. The Nearctic and Palaearctic regions share lineages because of their parallel biogeographic histories and ecological conditions. As the number of phylogenetic studies increases, there are more insights into past exchange events between these two regions and their effects on the current distribution of diversity. However, several groups have not been tested and an overall generalization is still missing. Here, we analyse the biogeographic history across multiple genera of odonates to elucidate a general process of species exchange, vicariance and species divergence between these two regions. Location The Holarctic, including the entire Nearctic and the East and West Palaearctic. Taxon 14 genera of Odonata (Insecta). Methods We reconstructed a time-calibrated phylogenetic tree for each genus to determine species relationships and divergence time using 3614 COI sequences of 259 species. Biogeographic ancestral range estimation was inferred for each phylogeny using BioGeoBEARS. Preferred habitat (lotic versus lentic) was established for each species. Results Exchange events were not restricted in time, direction or either lentic habitat or lotic habitat. Most genera crossed between both regions only once, and it was mainly across the Beringia, while three diverse anisopteran genera revealed multiple exchanges. Recent exchanges during the Pleistocene were associated with cold-dwelling and lentic species. Main Conclusions Our finding reveals the absence of a generalizable pattern of species exchange and divergence between the Nearctic and Palaearctic regions; instead, we found lineage-specific biogeographic patterns. This finding highlights the complexity of drivers and functional traits that shaped current diversity patterns. Moreover, it emphasizes that general conclusions cannot be formulated based on one single clade.
Temporal and spatial variation in trophic scenarios affects population demographic heterogeneity in Bonelli's Eagle (Aquila fasciata)
(Wiley, 2024-08-21) Hernández Matías, Antonio, 1974-; Peragon, Iván; Resano Mayor, Jaime; Moleón, Marcos; Virgós, Emilio; Real, Joan
The recognition of individual variation has fundamental implications for ecological, evolutionary and biodiversity conservation. There is increasing theoretical interest in how spatial and temporal variation in the environment can create differences in the demographic contribution of individuals over space and time. However, empirical information about the characteristics of the environmental drivers of key vital rates and their spatiotemporal variation is still scarce. Here, we used data generated by a monitoring scheme (1990–2015) of a population of a long-lived territorial avian predator, Bonelli’s Eagle Aquila fasciata, which included estimations of individuals’ diet through stable isotope analysis (2008–15), to evaluate whether temporal consistency in spatially structured dietary patterns affects key demographic parameters, namely productivity and survival, at territory scales. We found strong within-population heterogeneity in survival and reproduction rates associated with Eagle territories, with territory average values ranging, respectively, from 0.58 to 1.00 and from 0 to 1.71 for the overall study period. Reproduction and survival were predictable over, respectively, 4- and 3-year periods for the bulk of the population, which suggests that the environmental drivers of these vital rates changed at these temporal scales. Interestingly, the characteristics of and the temporal variation in the diets of territorial individuals during these periods were associated with their survival and reproduction. Based on these findings, we suggest that spatial and temporal variations in trophic scenarios potentially act as meaningful drivers of intrapopulation demographic heterogeneity.
Tempo and mode of diversification of the red devil spiders (Araneae: Dysderidae) of the Canary Islands.
(Wiley, 2024-11-27) Bellvert Bantí, Adrià; Pollock, Laura J.; Kaliontzopoulou, Antigoni; Arnedo Lombarte, Miquel Àngel
The study of adaptive radiations has shed light on our current understanding of evolution. However, previous studies examining the mode in which species diversified, how diversification rates varied, and how ecological specialisation affected these processes have found few different results across different taxa and geographic and ecological systems, showing how complex this process is. To gain a more complete picture of how species evolve, additional model systems that encompass alternative ecological requirements are needed. Here, we present the results of a study aimed at unravelling the diversification mode and evolutionary drivers of the spider genus Dysdera, the red devil spiders, endemic to the Canary Islands. These species exhibit remarkable phenotypic variability in their mouthparts, which has been related to different levels of specialisation in the predation of isopods. We explored patterns of lineage diversification and assessed the role of trophic specialisation as a driver of species diversification. Additionally, we used climatic variables, occurrence data and morphological information to unravel the underlying mode of speciation by means of joint species distribution models and age-range correlation methods. Our results reveal that red devil spiders underwent an early burst of diversification, followed by a slowdown of diversification rates, which is a hallmark of adaptive radiation. We also found evidence that the trophic morphology shaped diversification, with specialist species exhibiting higher rates of diversification. Finally, our analyses suggest that speciation occurred mostly in allopatry, with subsequent secondary sympatry following range expansión.
Spatio-temporal patterns of carnivore guild related to theirprey in a Mediterranean landscape
(Wiley, 2024-12-10) Peris, Albert; Mampel, Toni; Vilella, Marc; Pons i Julià, Daniel; Real, Joan; Puig-Gironès, Roger
Small mammal populations fluctuate significantly in abundance over time, affecting the entire food web. However, changes in their occupancy across a landscape receive less attention. While habitat features are relevant for some predators, diet specialization and prey distribution and abundance might play an important role in shaping predator populations. Using a multi-season occupancy analysis, we examined the spatio-temporal patterns of Mediterranean mesocarnivores—common genet, stone marten and red fox—focusing on the factors that influence their occupancy dynamics, particularly small mammal occupancy as a prey resource. Data was collected from December 2020 to May 2021 in the Sant Llorenc del Munt i l’Obac Natural Park using a camera-trap grid. We analysed small mammal occupancy dynamics and used these as covariates in predator occupancy models to explore predator–prey relationships. Additionally, we included the occurrence of each carnivore as a predictor for interspecific analysis, and kernel density functions were used to assess daily activity overlaps. Results showed that interspecific competitionsignificantly affected mesocarnivore occupancy, as genet occupancy was negatively correlated with the red fox occupancy. Although prey occurrence did not influence mesocarnivore occupancy, it did affect detectability, with genet and stone marten detectability being positively related to small mammal presence and high daily activity overlap between predators and prey. This suggests that mesopredators respond rapidly to prey abundance, highlighting the intricate temporal dependence between predator activity and prey occupancy. Dynamic occupancy and activity models provide a deeper understanding of predator–prey relationships at the local scale.
Modelling the Distribution of Key Mediterranean Gorgonians: An Ensemble Approach to Unravel Broad-Scale Patterns and Guide Conservation Efforts
(John Wiley & Sons, 2024-11-22) Amblàs i Novellas, David; Matos, Fábio L.; Linares Prats, Cristina; Figuerola-Ferrando, Laura; Zentner, Yanis; Garrabou, Joaquim
Aim Determining the species distribution and factors shaping it is a major challenge for conservation planning. Ecological niche models (ENMs) facilitate the comprehension of how environmental factors may influence species occurrence, providing spatially explicit information relevant to conservation. Therefore, our aim was to estimate the potential distribution of key habitat-forming Mediterranean gorgonians, whose conservation would protect many co-occurring species. Location Mediterranean Sea. Methods We modelled the potential distribution of the Mediterranean gorgonians Eunicella singularis, Eunicella cavolini, Paramuricea clavata and Corallium rubrum, using an ensemble ENM that combines nine algorithms. An extensive dataset of presence records (> 4378) collected through scientific surveys and citizen-science was intersected with oceanographic and topographic information within the coralligenous habitat depth range (< 150 m). This approach was used to map the habitat suitability of the study area for each species, assess related uncertainty, identify the most important factors shaping their distribution, and evaluate the overlap with the current network of Marine Protected Areas. Results The model identified higher habitat suitability for the occurrence of each gorgonian species in the NW Mediterranean, with roughness and temperature as the main drivers of their distribution. Conversely, the poorly sampled SE Mediterranean showed low habitat suitability, although there is a greater uncertainty associated with this estimate. The combined potential distribution of the four species is estimated to cover a quarter of Mediterranean shallow and mesophotic waters, but only 19% was included within protected areas. Main Conclusions The habitat suitability and uncertainty maps provide a valuable tool for the conservation and management of Mediterranean gorgonian species by offering spatially explicit information critical for marine spatial planning. The model estimates of habitat suitability showed low uncertainty for most of the study area, with few exceptions in the SE Mediterranean. Further studies, particularly in the SE Mediterranean will contribute to validate these results and will provide new information to improve future modelling efforts.
Mediterranean octocoral populations exposed to marine heatwaves are less resilient to disturbances
(Wiley, 2024-09-14) Capdevila Lanzaco, Pol; Zentner, Yanis; Rovira Mestres, Graciel·la; Garrabou, Joaquim; Medrano Cuevas, Alba; Linares Prats, Cristina
[eng] The effects of climate change are now more pervasive than ever. Marine ecosystems have been particularly impacted by climate change, with marine heatwaves (MHWs) being a strong driver of mass mortality events. Even in the most optimistic greenhouse gas emission scenarios, MHWs will continue to increase in frequency, intensity and duration. For this reason, understanding the resilience of marine species to the increase of MHWs is crucial to predicting their viability under future climatic conditions. In this study, we explored the consequences of MHWs on the resilience (the ability of a population to resist and recover after a disturbance) of a Mediterranean key octocoral species, Paramuricea clavata, to further disturbances to their population structure. To quantify P. clavata's capacity to resist and recover from future disturbances, we used demographic information collected from 1999 to 2022, from two different sites in the NW Mediterranean Sea to calculate the transient dynamics of their populations. Our results showed that the differences in the dynamics of populations exposed and those not exposed to MHWs were driven mostly by differences in mean survivorship and growth. We also showed that after MHWs P. clavata populations had lower resistance and slower rates of recovery than those not exposed to MHWs. Populations exposed to MHWs had lower resistance elasticity to most demographic processes compared to unexposed populations. In contrast, the only demographic process showing some differences when comparing the speed of recovery elasticity values between populations exposed and unexposed to MHWs was stasis. Finally, under scenarios of increasing frequency of MHWs, the extinction of P. clavata populations will accelerate and their capacity to resist and recover after further disturbances will be hampered. Overall, these findings confirm that future climatic conditions will make octocoral populations even more vulnerable to further disturbances. These results highlight the importance of limiting local impacts on marine ecosystems to dampen the consequences of climate change.
Interactive effects of Orobanche latisquama parasitism and drought stress in Salvia rosmarinus plants growing under Mediterranean field conditions
(Wiley, 2024-12-06) Jené Vinuesa, Laia; Massó Rodríguez, Marcel; Munné Bosch, Sergi
Mediterranean-type ecosystems are recognized as critical hotspots for both biodiversity and climate change. Within these environments, plants often interact with diverse species, including holoparasitic plants, while simultaneously facing increasing episodes of precipitation shortages and rising temperatures. Here, we investigated the impact of Orobanche latisquama Reut. ex Boiss infestation on the Mediterranean shrub Salvia rosmarinus (L.) Spenn (rosemary) across three populations along an altitudinal gradient, focusing on its effects on host tolerance and resilience to severe summer drought in its natural habitat. Results showed no major physiological impact of the parasite on the host during spring but revealed an enhanced photo- and antioxidant-protective response during the summer drought in rosemary plants infested with O. latisquama. Infested plants showed elevated contents of α-tocopherol and a shift in the ascorbate ratio towards its oxidized state during the summer, particularly in upper and sun-exposed leaves. This was accompanied by elevated malondialdehyde content, indicating enhanced lipid peroxidation. However, despite the heightened photo-oxidative stress observed in leaves from infested plants, no damage to photosystem II was observed, indicating a good tolerance of rosemary to the interaction between parasitism and drought. By autumn, all plants displayed similar recovery patterns, and the differences between infested and non-infested plants disappeared, thus indicating a high resilience to the combination of these biotic and abiotic stresses. Overall, these findings underscore the great adaptive mechanisms S. rosmarinus plants have evolved to endure severe summer drought, even when challenged by holoparasitic plant infestation, and provide new insights into plant-parasite interactions in Mediterranean-type ecosystems.
Differential response of roots and leaves to combined heat and salinity stresses in tomato plants
(Elsevier B.V., 2024-10-01) Mesa Parra, Tania; Romero, Agustí; Munné Bosch, Sergi
Despite our understanding of plant responses to single stresses, knowledge on how plants respond to combined abiotic factors and the underlying hormonal regulation is still very limited. Here, we aimed to examine the plant response to combined heat and salt stresses in tomato plants, the underlying hormonal response and the effectiveness of methyl jasmonate application in its alleviation. We measured fruit production and various stress markers in both roots and leaves, together with endogenous contents of stress-related phytohormones (including abscisic acid, salicylic acid and jasmonates) in tomato plants (Solanum lycopersicum cv. Micro-Tom), exposed to combined stress. In addition, we evaluated the effectiveness of a methyl jasmonate treatment as a priming agent to alleviate the negative effects of stress, with an emphasis on evaluating the effects of this hormone on triggering antioxidant protection by enhancement of vitamin E contents. Plants responded differently to combined stress treatment than to single stresses, but this differential response was organ-specific, with roots being more sensitive to stress than leaves. Both abscisic acid and jasmonates were involved in the plant response to combined stress but leaves and roots responded differently. Furthermore, abscisic acid and jasmonates correlated with vitamin E accumulation, most particularly in roots. Foliar application of methyl jasmonate at the flowering stage in plants challenged with combined stress did not improve fruit production but resulted in enhanced vitamin E accumulation in leaves. It is concluded that (i) roots and leaves show a differential sensitivity to both single and combined heat and salt stresses, (ii) the response of abscisic acid and jasmonates in plant stress responses seems to be markedly organ dependent, and (iii) foliar methyl jasmonate increased vitamin E accumulation under combined stress in tomato plants.
Trophic plasticity in the sea urchin Paracentrotus lividus, as a function of resource availability and habitat features
(Inter-Research, 2020) Camps Castellà, Judith; Romero, Javier; Prado Villegas, Patricia
Factors controlling herbivory pressure are of central importance in shaping the sea-scape. In the Mediterranean, the sea urchin Paracentrotus lividus is considered as a keystone her-bivore in seagrass meadows and macroalgal communities. Here we explored the trophic behaviorof this sea urchin in a shallow seagrass habitat of Cymodocea nodosa mixed with Caulerpa prolif-era and interspersed with sandy areas in Alfacs Bay, Ebro Delta (NW Mediterranean). The sea-sonal pseudo-indigenous bryozoan Amathia verticillata is locally very abundant, and there is alsoan important population of pen shells Pinna nobilis, providing hard substrate and cover, thusbeing a unique environment for assessing sea urchin trophic behavior. To this end, we conductedan ensemble of food preference and foraging experiments and stomach content and stable isotopeanalyses. Our results showed that sea urchins strongly prefer A. verticillata over other localresources, and there was also an important presence of the bryozoan in stomach contents (ca.44%), coupled with green and decayed seagrass leaves. Stable isotope analyses revealed thatover the long term, ca. 65% of the diet of P. lividus was based on decayed seagrass leaves, fol-lowed by the bryozoan and green seagrass leaves (21.7 and 13.3%, respectively). The localavailability of P. nobilis provides a preferred substrate for sea urchins, which showed limitedforaging movements into the surrounding seagrass beds, particularly when A. verticillata wasattached to the pen shells. The apparently high contribution of animal and detrital food to P. lividus diet is unprecedented, and suggests an opportunistic feeding behavior in sea urchins in those habitats.
Trophic plasticity in the sea urchin Paracentrotus lividus, as a function of resource availability and habitat features
(Inter-Research, 2020) Camps Castellà, Judith; Romero, Javier (Romero Martinengo); Prado Villegas, Patricia
Factors controlling herbivory pressure are of central importance in shaping the sea-scape. In the Mediterranean, the sea urchin Paracentrotus lividus is considered as a keystone her-bivore in seagrass meadows and macroalgal communities. Here we explored the trophic behaviorof this sea urchin in a shallow seagrass habitat of Cymodocea nodosa mixed with Caulerpa prolifera> and interspersed with sandy areas in Alfacs Bay, Ebro Delta (NW Mediterranean). The seasonal pseudo-indigenous bryozoan Amathia verticillata is locally very abundant, and there is alsoan important population of pen shells Pinna nobilis, providing hard substrate and cover, thus being a unique environment for assessing sea urchin trophic behavior. To this end, we conductedan ensemble of food preference and foraging experiments and stomach content and stable isotopeanalyses. Our results showed that sea urchins strongly prefer A. verticillata over other localresources, and there was also an important presence of the bryozoan in stomach contents (ca.44%), coupled with green and decayed seagrass leaves. Stable isotope analyses revealed thatover the long term, ca. 65% of the diet of P. lividus was based on decayed seagrass leaves, followed by the bryozoan and green seagrass leaves (21.7 and 13.3%, respectively). The localavailability of P. nobilis provides a preferred substrate for sea urchins, which showed limitedforaging movements into the surrounding seagrass beds, particularly when A. verticillata wasattached to the pen shells. The apparently high contribution of animal and detrital food to P. lividus diet is unprecedented, and suggests an opportunistic feeding behavior in sea urchins in those habitats.
Revisiting Chilean gorgonians (Cnidaria: Octocorallia: Gorgoniidae): taxonomic clarification and molecular phylogeny of Leptogorgia chilensis and Phycogorgia fucata.
(Taylor & Francis, 2025-12-15) Camps Castellà, Judith; Vargas, Sergio; Vera Escalona, Iván; Prado Villegas, Patricia; Hinojosa, Iván A.; Brante, Antonio
Most biodiversity studies of eastern Pacific octocorals have focused on the tropical shallow waters from Mexico to Peru, and more recently, on those off Chile. The first description of a Chilean octocoral dates back to the H.M.S. Challenger expedition (1873–1876), and since then, only a few descriptions of new coral species have been published from this region. In addition, the taxonomic status of most gorgonians reported from the temperate Pacific coast of South America remains uncertain due to the loss of the original type material. In this study, we use morphological characters and nuclear and mitochondrial markers to re-evaluate the taxonomy of the Chilean gorgonians Phycogorgia fucata and Leptogorgia chilensis. Our findings support the monophyly of Chilean Leptogorgia, confirm that Leptogorgia chilensis from Chile is distinct from specimens identified as the same species in California, and reveal that P. fucata, despite its unique morphology, should be included in the genus Leptogorgia.
Seeing through the gray box: an integrated approach to physiological modeling ofphytoplankton stoichiometry
(Frontiers Media, 2024-12-09) Jones, Catriona L. C.; Camps Castellà, Judith; Smykala, Mike; Sobol, Morgan S.; Inomura, Keisuke
The‘black boxes’ of ecological stoichiometry, planktonic microbes, have longbeen recognized to have considerable effects on global biogeochemical cycles.Signi cant progress has been made in studying these effects and expanding ourunderstanding of microbial stoichiometry. However, the‘black box’ has not beencompletely cracked open; there remain gaps in our knowledge of the fate ofelements within the phytoplankton cell, and the effect of external processes onnutrient uxes through their metabolism and into macromolecules and biomass -the eponymous‘gray box’. In this review paper, we describe the development of anintegrative modeling approach that involves a stoichiometrically explicit model ofMacromolecular Allocation and Genome-scale Metabolic Analysis (MAGMA) togain insights into the intra- and extracellular fluxes of nutrients using thecyanobacterium Parasynechococcus marenigrum WH8102 as a target modelorganism. We then describe an example of the genome-scale resources for P.marenigrum that can be used to build such an integrated modeling tool to seethrough the gray box of phytoplankton stoichiometry and improve ourunderstanding of the effects of resource supplies and other environmentaldrivers, especially temperature, on C:N:P demand, acquisition, and allocation atthe cellular level.
Blue LED light improves the antioxidant composition of Valencia oranges during postharvest: Impact on orange juice, pulp portion and peel residue
(Elsevier B.V., 2024-12-01) Mesa Parra, Tania; Romero, Agustí; Munné Bosch, Sergi
Valencia orange is the major citrus fruit produced worldwide and its outstanding health benefits are well-established. However, there is a pressing need to further enhance the nutritional quality of fruits and to revalorize the resulting residues, providing benefits for both public health and the environment. Here, Valencia oranges were exposed to blue LED light for 30 days at room temperature in controlled environment chambers, using darkness as a control. Examination of the blue LED light effects was performed focusing on visual aspects, weight loss, organoleptic properties, antioxidant content and oxidation status, together with the analysis of the phytohormonal profile. Blue LED light was found to boost fruit weight loss, particularly through dehydration of the peel, without altering pulp firmness or external appearance. Organoleptic quality, including texture and flavor, as well as total soluble sugar and acidity remained unchanged. Notably, blue LED light increased antioxidant levels, more specifically vitamin C and total phenols in the juice, and enhanced total antioxidant capacity in the peel. This suggests that blue LED light can enhance nutritional quality while preserving organoleptic properties. The increase in antioxidants is likely a protective response against photooxidative stress induced by the blue LED light. These findings highlight the potential of blue LED light to improve postharvest fruit quality with direct health benefits and support a circular economy by enhancing the value of orange peel waste.
Functional mechanisms underlying the persistence of Opuntia ficus-indica in a Mediterranean-type ecosystem after fire
(Elsevier, 2024-10-01) Santos, Jessyca A.S.; Villadangos Redondo, Sabina; Garcia, Queila S.; Munné Bosch, Sergi
Changes in fire regime can favor invasive plants in Mediterranean-type ecosystems. The goal of this experiment was to understand the post-fire dynamics of the invasive cactus, Opuntia ficus-indica, by assessing the contribution and impact of clonal propagation and sexual reproduction on the recruitment of this species after fire. The number of O. ficus-indica new clones and seed-derived plants was estimated after a burn event in a natural area located in the western Mediterranean (Catalonia, NE Spain). Functional stress markers, relative growth rate, and contents of both growth- and stress-related phytohormones were measured. Furthermore, remaining plants damaged by fire were evaluated regarding fruit size, seed number, and viability, as well as other reproductive traits. Results showed that 95 % of the new recruits in the burned area were clones. Clones showed a higher water and chlorophyll content than seed-derived plants. The relative growth rate was consequently higher in clones than in seed-derived plants, which was also associated with higher contents of growth-related hormones (cytokinins and gibberellins) in the former. Furthermore, seeds produced by burned plants exhibited a thicker funicular envelope compared to seeds from unburned plants. It is concluded that, although clonal propagation was the main reproductive strategy observed after fire, its combination with sexual reproduction and efficient physiological strategies of survival guarantees persistence of this invasive plant species in burned areas due to an effective and fast recovery in cactus cover in the short term while contributing to the genetic variability in the population in the long term.
Trophic history of Hawaiian green turtles as revealed by stable isotope ratios (δ13C, δ15N and δ34S) in the bones of museum specimens
(John Wiley & Sons, 2024-01-11) Velásquez Vacca, Adriana; Seminoff, Jeffrey A.; Jones, T. Todd; Balazs, George H.; Cardona Pascual, Luis
Understanding consumer trophic status and long-term dietary changes can yield information about impacts of altered habitats on their ecology. In Hawai'i, coastal ecosystems have been significantly modified by the introduction of invasive seaweeds and mangroves, high nutrient load and overfishing, but so far, much is still to be understood about how these changes have affected the green turtle (Chelonia mydas). This study analyzed stable carbon, nitrogen, and sulfur isotope ratios in the bone tissue of modern and museum specimens of green turtles collected from 1901 to 2020 in Oahu and the North-western Hawaiian Islands to understand how their isotopic niche has changed through time, a crucial step towards restoring the ecological role of a formerly decimated species. The standard ellipse size and the total area of the convex hull of the isotopic niche of green turtles in three periods (1901–1951, 1992–2008, and 2018–2020) were calculated. The stable isotope values of ancient green turtles (1901–1951) suggest that they relied heavily on macroalgae even before the introduction of exotic species and eutrophication promoted the development of algal pastures. However, a few ancient green turtles relied heavily on seagrasses, and others complemented their macroalgae-based diets with significant amounts of animal matter. Such diet specialists were missing from the sample of current green sea turtles, suggesting that these foraging strategies are less common or perhaps even absent in the current population. The results suggest that green turtles have converged on the use of the most abundant resource, red macroalgae, likely because of the homogenization and simplification of coastal habitats and food webs due to anthropogenic influences. Restoring the population size of herbivorous fishes and a more diverse ecosystem structure may be necessary to recover the array of trophic strategies formerly present in the Hawaiian green turtle population.

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