Browsing by Author "Duarte, Carlos M."
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- A population genetics toolbox for the threatened canopy-forming brown seaweeds Cystoseira tamariscifolia and C-amentacea (Fucales, Sargassaceae)Publication . Engelen, Aschwin; Costa, Joana; Bermejo, Ricardo; Marba, NAria; Duarte, Carlos M.; Serro, Ester A.The brown macroalga Cystoseira tamariscifolia is a foundation species along the northeastern Atlantic and western Mediterranean Sea. It occurs from lower intertidal rock pools to the shallow subtidal. Anthropogenic pollution and rising seawater temperatures can threaten its local distributions. In order to address impacts of historical and current environmental changes, to quantify effective dispersal and population connectivity, and to provide genetic tools for restoration and coastal management strategies, we have developed ten microsatellite markers, validated on 48 individuals from a single population. With 2-11 alleles per locus, the observed heterozygosity varied between 0.244 and 0.875. All of the developed microsatellites cross-amplified also on Cystoseira amentacea. The ten microsatellite loci developed here show high genetic diversity, making them useful for connectivity and population genetic studies aimed at small to large spatial scales, and provide essential insight for the development of conservation strategies for this important but threatened foundation species.
- 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.
- Corrigendum to “Golden carbon of Sargassum forests revealed as an opportunity for climate change mitigation” [Sci. Total Environ., 729 (2020) Start page – End page/ 138745]Publication . Gouvêa, Lidiane P.; Assis, J.; Gurgel, Carlos F.D.; Serrao, Ester; Silveira, Thiago C.L.; Santos, Rui; Duarte, Carlos M.; Peres, Leticia M.C.; Carvalho, Vanessa; Batista, Manuela; Bastos, Eduardo; Sissini, Marina N.; Horta, Paulo A.
- Corrigendum: Imprint of climate change on Pan-Arctic marine vegetationPublication . Krause-Jensen, Dorte; Archambault, Philippe; Assis, Jorge; Bartsch, Inka; Bischof, Kai; Filbee-Dexter, Karen; Dunton, Kenneth H.; Maximova, Olga; Ragnarsdóttir, Sunna Björk; Sejr, Mikael K.; Simakova, Uliana; Spiridonov, Vassily; Wegeberg, Susse; Winding, Mie H. S.; Duarte, Carlos M.In the original article, there were mistakes in Tables 2–4 and associated legends and text as published. The original article contained errors in the reported modeled macroalgal distribution area in the pan-Arctic and its subregions because the polygons used to calculate the areas were not correctly defined. A correction has been made to Tables 2–4 and their associated legends: The Table legends missed the word “brown” and an explanatory note. The corrected Tables 2–4 and associated legends appear below (corrections marked in bold).
- Decreasing carbonate load of seagrass leaves with increasing latitudePublication . Mazarrasa, Ines; Marba, Nuria; Krause-Jensen, Dorte; Kennedy, Hilary; Santos, Rui; Lovelock, Catherine E.; Duarte, Carlos M.Seagrass meadows play a significant role in the formation of carbonate sediments, serving as a substrate for carbonate-producing epiphyte communities. The magnitude of the epiphyte load depends on plant structural and physiological parameters, related to the time available for epiphyte colonization. Yet, the carbonate accumulation is likely to also depend on the carbonate saturation state of seawater (Omega) that tends to decrease as latitude increases due to decreasing temperature and salinity. A decrease in carbonate accumulation with increasing latitude has already been demonstrated for other carbonate producing communities. The aim of this study was to assess whether there was any correlation between latitude and the epiphyte carbonate load and net carbonate production rate on seagrass leaves. Shoots from 8 different meadows of the Zostera genus distributed across a broad latitudinal range (27 degrees S to up to 64 degrees N) were sampled along with measurements of temperature and Omega. The Omega within meadows significantly decreased as latitude increased and temperature decreased. The mean carbonate content and load on seagrass leaves ranged from 17% DW to 36% DW and 0.4-2.3 mg CO3 cm(-2), respectively, and the associated mean carbonate net production rate varied from 0.007 to 0.9 mg CO3 cm(-2) d(-1). Mean carbonate load and net production rates decreased from subtropical and tropical, warmer regions towards subpolar latitudes, consistent with the decrease in Omega. These results point to a latitudinal variation in the contribution of seagrass to the accumulation of carbonates in their sediments which affect important processes occurring in seagrass meadows, such as nutrient cycling, carbon sequestration and sediment accretion.
- Disentangling the Influence of Mutation and Migration in Clonal Seagrasses Using the Genetic Diversity Spectrum for MicrosatellitesPublication . ARNAUD-HAOND, Sophie; Moalic, Yann; Hernandez-Garcia, Emilio; Eguíluz, Víctor M.; Alberto, Filipe; Serrao, Ester A.; Duarte, Carlos M.The recurrent lack of isolation by distance reported at regional scale in seagrass species was recently suggested to stem from stochastic events of large-scale dispersal. We explored the usefulness of phylogenetic information contained in microsatellite loci to test this hypothesis by using the Genetic Diversity Spectrum (GDS) on databases containing, respectively, 7 and 9 microsatellites genotypes for 1541 sampling units of Posidonia oceanica and 1647 of Cymodocea nodosa. The simultaneous increase of microsatellite and geographic distances that emerges reveals a coherent pattern of isolation by distance in contrast to the chaotic pattern previously described using allele frequencies, in particular, for the long-lived P. oceanica. These results suggest that the lack of isolation by distance, rather than the resulting from rare events of large-scale dispersal, reflects at least for some species a stronger influence of mutation over migration at the scale of the distribution range. The global distribution of genetic polymorphism may, therefore, result predominantly from ancient events of step-by-step (re) colonization followed by local recruitment and clonal growth, rather than contemporary gene flow. The analysis of GDS appears useful to unravel the evolutionary forces influencing the dynamics and evolution at distinct temporal and spatial scales by accounting for phylogenetic information borne by microsatellites, under an appropriate mutation model. This finding adds nuance to the generalization of the influence of large-scale dispersal on the dynamics of seagrasses.
- Gene pool and connectivity patterns of Pinna nobilis in the Balearic Islands (Spain, Western Mediterranean Sea): Implications for its conservation through restockingPublication . Gonzalez-Wanguemert, Mercedes; Basso, Lorena; Balau, Ana; Costa, Joana; Renault, Lionel; Serrao, Ester; Duarte, Carlos M.; Hendriks, Iris E.Pinna nobilis is an endemic bivalve of the Mediterranean Sea, and a vulnerable species registered as endangered and protected under the European Council Directive 92/43/EEC and Barcelona Convention. In early autumn 2016, a mass mortality event impacted P. nobilis populations in the south-western Mediterranean Sea, including the Balearic Islands. At the time of this study, P. nobilis still maintained high population densities along the Balearic coasts (Western Mediterranean). This study evaluated the connectivity of P. nobilis post-larvae and adults in seagrass habitats around the Balearic Islands and identified its source and sink populations. These objectives were reached through a multidisciplinary approach including population genetics (10 microsatellites) and hydrodynamic modelling. High genetic diversity was found and significant genetic differentiation (inferred by fixation index F-ST) was detected between post-larvae samples, but not between adult populations. Significant genic and genotypic differentiation was recorded for adults and post-larvae. This pattern was confirmed by correspondence analysis using allele frequencies. The genetic connectivity pattern was consistent with marine currents and dispersal models. This work not only improves knowledge of the P. nobilis gene pool in south-west Mediterranean populations and their connectivity patterns, but is also crucial to help evaluate the possibility of recovery from source populations and the possibility of restocking programmes, as well as provide a solid base to establish effective marine reserve networks.
- Genetic and oceanographic tools reveal high population connectivity and diversity in the endangered pen shell Pinna nobilisPublication . Wesselmann, Marlene; Gonzalez-Wanguemert, Mercedes; Serrao, Ester A.; Engelen, Aschwin H.; Renault, Lionel; Garcia-March, Jose R.; Duarte, Carlos M.; Hendriks, IrisFor marine meta-populations with source-sink dynamics knowledge about genetic connectivity is important to conserve biodiversity and design marine protected areas (MPAs). We evaluate connectivity of a Mediterranean sessile species, Pinna nobilis. To address a large geographical scale, partial sequences of cytochrome oxidase I (COI, 590 bp) were used to evaluate phylogeographical patterns in the Western Mediterranean, and in the whole basin using overlapping sequences from the literature (243 bp). Additionally, we combined (1) larval trajectories based on oceanographic currents and early life-history traits and (2) 10 highly polymorphic microsatellite loci collected in the Western Mediterranean. COI results provided evidence for high diversity and low inter-population differentiation. Microsatellite genotypes showed increasing genetic differentiation with oceanographic transport time (isolation by oceanographic distance (IBD) set by marine currents). Genetic differentiation was detected between Banyuls and Murcia and between Murcia and Mallorca. However, no genetic break was detected between the Balearic populations and the mainland. Migration rates together with numerical Lagrangian simulations showed that (i) the Ebro Delta is a larval source for the Balearic populations (ii) Alicante is a sink population, accumulating allelic diversity from nearby populations. The inferred connectivity can be applied in the development of MPA networks in the Western Mediterranean.
- Global analysis of seagrass restoration: the importance of large-scale plantingPublication . van Katwijk, Marieke M.; Thorhaug, Anitra; Marba, Nuria; Orth, Robert J.; Duarte, Carlos M.; Kendrick, Gary A.; Althuizen, Inge H. J.; Balestri, Elena; Bernard, Guillaume; Cambridge, Marion L.; Cunha, Alexandra; Durance, Cynthia; Giesen, Wim; Han, Qiuying; Hosokawa, Shinya; Kiswara, Wawan; Komatsu, Teruhisa; Lardicci, Claudio; Lee, Kun-Seop; Meinesz, Alexandre; Nakaoka, Masahiro; O'Brien, Katherine R.; Paling, Erik I.; Pickerell, Chris; Ransijn, Aryan M. A.; Verduin, Jennifer J.In coastal and estuarine systems, foundation species like seagrasses, mangroves, saltmarshes or corals provide important ecosystem services. Seagrasses are globally declining and their reintroduction has been shown to restore ecosystem functions. However, seagrass restoration is often challenging, given the dynamic and stressful environment that seagrasses often grow in. From our world-wide meta-analysis of seagrass restoration trials (1786 trials), we describe general features and best practice for seagrass restoration. We confirm that removal of threats is important prior to replanting. Reduced water quality (mainly eutrophication), and construction activities led to poorer restoration success than, for instance, dredging, local direct impact and natural causes. Proximity to and recovery of donor beds were positively correlated with trial performance. Planting techniques can influence restoration success. The meta-analysis shows that both trial survival and seagrass population growth rate in trials that survived are positively affected by the number of plants or seeds initially transplanted. This relationship between restoration scale and restoration success was not related to trial characteristics of the initial restoration. The majority of the seagrass restoration trials have been very small, which may explain the low overall trial survival rate (i.e. estimated 37%). Successful regrowth of the foundation seagrass species appears to require crossing a minimum threshold of reintroduced individuals. Our study provides the first global field evidence for the requirement of a critical mass for recovery, which may also hold for other foundation species showing strong positive feedback to a dynamic environment.Synthesis and applications. For effective restoration of seagrass foundation species in its typically dynamic, stressful environment, introduction of large numbers is seen to be beneficial and probably serves two purposes. First, a large-scale planting increases trial survival - large numbers ensure the spread of risks, which is needed to overcome high natural variability. Secondly, a large-scale trial increases population growth rate by enhancing self-sustaining feedback, which is generally found in foundation species in stressful environments such as seagrass beds. Thus, by careful site selection and applying appropriate techniques, spreading of risks and enhancing self-sustaining feedback in concert increase success of seagrass restoration.For effective restoration of seagrass foundation species in its typically dynamic, stressful environment, introduction of large numbers is seen to be beneficial and probably serves two purposes. First, a large-scale planting increases trial survival - large numbers ensure the spread of risks, which is needed to overcome high natural variability. Secondly, a large-scale trial increases population growth rate by enhancing self-sustaining feedback, which is generally found in foundation species in stressful environments such as seagrass beds. Thus, by careful site selection and applying appropriate techniques, spreading of risks and enhancing self-sustaining feedback in concert increase success of seagrass restoration.
- Global biodiversity patterns of marine forests of brown macroalgaePublication . Fragkopoulou, Eliza; Serrao, Ester; De Clerck, Olivier; Costello, Mark J.; Araújo, Miguel B.; Duarte, Carlos M.; Krause‐Jensen, Dorte; Assis, JorgeAim Marine forests of brown macroalgae create essential habitats for coastal species and support invaluable ecological services. Here, we provide the first global analysis of species richness and endemicity of both the kelp and fucoid biomes. Location Global. Time period Contemporary. Major taxa studied Marine forests of brown macroalgae, formed by kelp (here defined as orders Laminariales, Tilopteridales and Desmarestiales) and fucoid (order Fucales), inhabiting subtidal and intertidal environments. Methods We coupled a large dataset of macroalgal observations (420 species, 1.01 million records) with a high-resolution dataset of relevant environmental predictors (i.e., light, temperature, salinity, nitrate, wave energy and ice coverage) to develop stacked species distribution models (stacked SDMs) and yield estimates of global species richness and endemicity. Results Temperature and light were the main predictors shaping the distribution of subtidal species, whereas wave energy, temperature and salinity were the main predictors of intertidal species. The highest regional species richness for kelp was found in the north-east Pacific (maximum 32 species) and for fucoids in south-east Australia (maximum 53 species), supporting the hypothesis that these regions were the evolutionary sources of global colonization by brown macroalgae. Locations with low species richness coincided between kelp and fucoid, occurring mainly at higher latitudes (e.g., Siberia) and the Baltic Sea, where extensive ice coverage and low-salinity regimes prevail. Regions of high endemism for both groups were identified in the Galapagos Islands, Antarctica, South Africa and East Russia. Main conclusions We estimated the main environmental drivers and limits shaping the distribution of marine forests of brown macroalgae and mapped biogeographical centres of species richness and endemicity, which largely coincided with the expectation from previous evolutionary hypotheses. The mapped biodiversity patterns can serve as new baselines for planning and prioritizing locations for conservation, management and climate change mitigation strategies, flagging threatened marine forest regions under different climate change scenarios.
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