Browsing by Author "Martins, Irene"
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- Climate change impacts on seagrass meadows and macroalgal forests: an integrative perspective on acclimation and adaptation potentialPublication . Duarte, Bernardo; Martins, Irene; Rosa, Rui; Matos, Ana R.; Roleda, Michael Y.; Reusch, Thorsten B. H.; Engelen, Aschwin; Serrao, Ester; Pearson, Gareth; Marques, João C.; Caçador, Isabel; Duarte, Carlos M.; Jueterbock, AlexanderMarine macrophytes are the foundation of algal forests and seagrass meadows-some of the most productive and diverse coastal marine ecosystems on the planet. These ecosystems provide nursery grounds and food for fish and invertebrates, coastline protection from erosion, carbon sequestration, and nutrient fixation. For marine macrophytes, temperature is generally the most important range limiting factor, and ocean warming is considered the most severe threat among global climate change factors. Ocean warming induced losses of dominant macrophytes along their equatorial range edges, as well as range extensions into polar regions, are predicted and already documented. While adaptive evolution based on genetic change is considered too slow to keep pace with the increasing rate of anthropogenic environmental changes, rapid adaptation may come about through a set of non-genetic mechanisms involving the functional composition of the associated microbiome, as well as epigenetic modification of the genome and its regulatory effect on gene expression and the activity of transposable elements. While research in terrestrial plants demonstrates that the integration of non-genetic mechanisms provide a more holistic picture of a species' evolutionary potential, research in marine systems is lagging behind. Here, we aim to review the potential of marine macrophytes to acclimatize and adapt to major climate change effects via intraspecific variation at the genetic, epigenetic, and microbiome levels. All three levels create phenotypic variation that may either enhance fitness within individuals (plasticity) or be subject to selection and ultimately, adaptation. We review three of the most important phenotypic variations in a climate change context, including physiological variation, variation in propagation success, and in herbivore resistance. Integrating different levels of plasticity, and adaptability into ecological models will allow to obtain a more holistic understanding of trait variation and a realistic assessment of the future performance and distribution of marine macrophytes. Such multi-disciplinary approach that integrates various levels of intraspecific variation, and their effect on phenotypic and physiological variation, is of crucial importance for the effective management and conservation of seagrasses and macroalgae under climate change.
- Ecological modelling and toxicity data coupled to assess population recovery of marine amphipod Gammarus locusta: Application to disturbance by chronic exposure to anilinePublication . de los Santos, Carmen B.; Neuparth, Teresa; Torres, Tiago; Martins, Irene; Cunha, Isabel; Sheahan, Dave; McGowan, Tom; Santos, Miguel M.A population agent-based model of marine amphipod Gammarus locusta was designed and implemented as a basis for ecological risk assessment of chemical pollutants impairing life-history traits at the individual level.We further used the modelto assess the toxic effects of aniline (a priority hazardous and noxious substance, HNS) on amphipod populations using empirically-built dose-response functions derived from a chronic bioassay that we previously performed with this species. We observed a significant toxicantinduced mortality and adverse effects in reproductive performance (reduction of newborn production) in G. locusta at the individual level. Coupling the population model with the toxicological data from the chronic bioassay allowed the projection of the ecological costs associated with exposure to aniline that might occur in wild populations. Model simulations with different scenarios indicated that even low level prolonged exposure to the HNS aniline can have significant long-term impacts on G. locusta population abundance, until the impacted population returns to undisturbed levels. This approach may be a useful complement in ecotoxicological studies of chemical pollution to transfer individual-collected data to ecological-relevant levels.
- Editorial: Emerging topics in coastal and transitional ecosystems: science, literacy, and innovationPublication . Duarte, Bernardo; Teixeira, Célia M.; Martins, Irene; Engelen, Aschwin; Costa, Raquel L.; Adams, Janine Barbara; Bebianno, Maria João; Melo, Ricardo A.; Fonseca, Vanessa F.Marine coastal and transitional ecosystems are facing increasing impacts, and often reflect the most immediate effects of environmental change, habitat destruction, and biodiversity loss. With over half of the population currently living in coastal areas, these areas are of interest for multiple uses and resources, as well as subjected to multiple stressors and associated impacts derived from local and upstream anthropogenic activities. The challenges coastal and transitional ecosystems now face is not new and have far-reaching implications for the ocean (Borja et al.). Nevertheless, significant knowledge gaps on their functioning and structure still exist and new solutions or approaches to this old problem are still needed, from blue biotechnological innovations to improved ocean literacy (Borja et al.). This Research Topic aimed to contribute to the sustainability of coastal and transitional environments, providing a broad overview of ecosystem resources and functioning, assessment and monitoring tools, restoration, biotechnology, and ocean literacy. A growing human population has also increased the reliance on the sea for food and feed resources. Despite soaring demand, the management of seafood resources is still hampered by key knowledge gaps on many life-history traits of target species as well as on ecosystem’s functioning (Golden et al., 2021). From tropical regions, where mangroves function as nursery habitats for various crustaceans and fish species, contributing to maintaining adjacent marine stocks, a poorly studied system on Príncipe Island, Gulf of Guinea, evidenced the importance of seasonality and mangrove zone on fish assemblages (Cravo et al.). In the deep sea, a particular challenge to commercial exploitation of fish species is how changing environmental conditions affect these organisms, which are generally characterized by high longevity, late reproduction, and low fecundity.
- Hypocholesterolaemic pharmaceutical simvastatin disrupts reproduction and population growth of the amphipod Gammarus locusta at the ng/L rangePublication . Neuparth, Teresa; Martins, Carla; de los Santos, Carmen B.; Costa, Maria H.; Martins, Irene; Costa, Pedro M.; Santos, Miguel M.Simvastatin (SIM), a hypocholesterolaemic drug, is among the most widely used pharmaceuticals worldwide and is therefore of emerging environmental concern. Despite the ubiquitous nature of SIM in the aquatic ecosystems, significant uncertainties exist about sublethal effects of the drug in aquatic organisms. Therefore, here we aimed at investigating a multi-level biological response in the model amphipod Gammarus locusta, following chronic exposures to low levels of SIM (64 ng/L to 8 mg/L). The work integrated a battery of key endpoints at individual-level (survival, growth and reproduction) with histopathological biomarkers in hepatopancreas and gonads. Additionally, an individual-based population modelling was used to project the ecological costs associated with long-term exposure to SIM at the population level. SIM severely impacted growth, reproduction and gonad maturation of G. locusta, concomitantly to changes at the histological level. Among all analysed endpoints, reproduction was particularly sensitive to SIM with significant impact at 320 ng/L. These findings have important implications for environmental risk assessment and disclose new concerns about the effects of SIM in aquatic ecosystems.