Browsing by Author "Krause-Jensen, Dorte"
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- Characterization of 12 polymorphic microsatellite markers in the sugar kelp Saccharina latissimaPublication . Paulino, Cristina; Neiva, J.; Coelho, Nelson C.; Aires, Tânia; Marba, Núria; Krause-Jensen, Dorte; Serrão, EsterSaccharina latissima is an ecologically and economically important kelp species native to the coastal regions of the Northern Hemisphere. This species has considerable phylogeographic structure and morphological plasticity, but lack of resolution of available genetic markers prevents a finer characterization of its genetic diversity and structure. Here, we describe 12 microsatellite loci identified in silico in a genomic library, and assess their polymorphism in three distant populations. Allelic richness at the species level was relatively high (5-23 alleles per locus), as was gene diversity within populations (0.42 < H (E) < 0.62). In addition, individuals readily form distinct genotypic clusters matching their populations of origin. The variation detected confirms the great potential of these markers to investigate the biogeography and population dynamics of S. latissima, and to better characterize its genetic resources for the establishing farming industry.
- 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.
- Differentiation in fitness-related traits in response to elevated temperatures between leading and trailing edge populations of marine macrophytesPublication . Mota, Catarina; Engelen, Aschwin; Serrao, Ester; Coelho, Márcio; Marba, Nuria; Krause-Jensen, Dorte; Pearson, GarethThe nature of species distribution boundaries is a key subject in ecology and evolution. Edge populations are potentially more exposed to climate-related environmental pressures. Despite research efforts, little is known about variability in fitness-related traits in leading (i.e., colder, high latitude) versus trailing (i.e., warmer, low latitude) edge populations. We tested whether the resilience, i.e. the resistance and recovery, of key traits differs between a distributional cold (Greenland) and warm (Portugal) range edge population of two foundation marine macrophytes, the intertidal macroalga Fucus vesiculosus and the subtidal seagrass Zostera marina. The resistance and recovery of edge populations to elevated seawater temperatures was compared under common experimental conditions using photosynthetic efficiency and expression of heat shock proteins (HSP). Cold and warm edge populations differed in their response, but this was species specific. The warm edge population of F. vesiculosus showed higher thermal resistance and recovery whereas the cold leading edge was less tolerant. The opposite was observed in Z. marina, with reduced recovery at the warm edge, while the cold edge was not markedly affected by warming. Our results confirm that differentiation of thermal stress responses can occur between leading and trailing edges, but such responses depend on local population traits and are thus not predictable just based on thermal pressures.
- Genetic diversity of Saccharina latissima (Phaeophyceae) along a salinity gradient in the North Sea-Baltic Sea transition zonePublication . Nielsen, Mette Moller; Paulino, Cristina; Neiva, J.; Krause-Jensen, Dorte; Bruhn, Annette; Serrão, EsterThe North Sea-Baltic Sea transition zone constitutes a boundary area for the kelp species Saccharina latissima due to a strong salinity gradient operating in the area. Furthermore, the existence of S.latissima there, along Danish waters, is fairly patchy as hard bottom is scarce. In this study, patterns of genetic diversity of S.latissima populations were evaluated along the salinity gradient area of Danish waters (here designated brackish) and were compared to reference sites (here designated marine) outside the gradient area, using microsatellite markers. The results showed that the S.latissima populations were structured into two clusters corresponding to brackish versus marine sites, and that gene flow was reduced both between clusters and between populations within clusters. In addition, results provided empirical evidence that marginal populations of S.latissima in the salinity gradient area exhibited a distinct genetic structure when compared to marine ones. Brackish populations were less diverse, more related, and showed increased differentiation over distance compared to marine populations. The isolation of the brackish S.latissima populations within the salinity gradient area of Danish waters in conjunction with their general low genetic diversity makes these populations vulnerable to ongoing environmental and climate change, predicted to result in declining salinity in the Baltic Sea area that may alter the future distribution and performance of S.latissima in the area.
- Glacial vicariance drives phylogeographic diversification in the amphi-boreal kelp Saccharina latissimaPublication . MACHADO, JOÃO NEIVA; Paulino, Cristina; Nielsen, Mette M.; Krause-Jensen, Dorte; Saunders, Gary W.; Assis, Jorge; Barbara, Ignacio; Tamigneaux, Eric; Gouveia, Licínia; Aires, Tânia; Marba, Nuria; Bruhn, Annette; Pearson, Gareth; Serrao, Ester A.Glacial vicariance is regarded as one of the most prevalent drivers of phylogeographic structure and speciation among high-latitude organisms, but direct links between ice advances and range fragmentation have been more difficult to establish in marine than in terrestrial systems. Here we investigate the evolution of largely disjunct (and potentially reproductively isolated) phylogeographic lineages within the amphi-boreal kelp Saccharina latissima s.l. Using molecular data (COI, microsatellites) we confirm that S. latissima comprises also the NE Pacific S. cichorioides complex and is composed of divergent lineages with limited range overlap and genetic admixture. Only a few genetic hybrids were detected throughout a Canadian Arctic/NW Greenland contact zone. The degree of genetic differentiation and sympatric isolation of phylogroups suggest that S. latissima s.l. represents a complex of incipient species. Phylogroup distributions compared with paleo-environmental reconstructions of the cryosphere further suggest that diversification within S. latissima results from chronic glacial isolation in disjunct persistence areas intercalated with ephemeral interglacial poleward expansions and admixture at high-latitude (Arctic) contact zones. This study thus supports a role for glaciations not just in redistributing pre-existing marine lineages but also as a speciation pump across multi-glacial cycles for marine organisms otherwise exhibiting cosmopolite amphi-boreal distributions.
- Global dataset of soil organic carbon in tidal marshesPublication . Maxwell, Tania L.; Rovai, André S.; Adame, Maria Fernanda; Adams, Janine B.; Álvarez-Rogel, José; Austin, William E. N.; Beasy, Kim; Boscutti, Francesco; Böttcher, Michael E.; Bouma, Tjeerd J.; Bulmer, Richard H.; Burden, Annette; Burke, Shannon A.; Camacho, Saritta; Chaudhary, Doongar R.; Chmura, Gail L.; Copertino, Margareth; Cott, Grace M.; Craft, Christopher; Day, John; de los Santos, Carmen B.; Denis, Lionel; Ding, Weixin; Ellison, Joanna C.; Ewers Lewis, Carolyn J.; Giani, Luise; Gispert, Maria; Gontharet, Swanne; González-Pérez, José A.; González-Alcaraz, M. Nazaret; Gorham, Connor; Graversen, Anna Elizabeth L.; Grey, Anthony; Guerra, Roberta; He, Qiang; Holmquist, James R.; Jones, Alice R.; Juanes, José A.; Kelleher, Brian P.; Kohfeld, Karen E.; Krause-Jensen, Dorte; Lafratta, Anna; Lavery, Paul S.; Laws, Edward A.; Leiva-Dueñas, Carmen; Loh, Pei Sun; Lovelock, Catherine E.; Lundquist, Carolyn J.; Macreadie, Peter I.; Mazarrasa, Inés; Megonigal, J. Patrick; Neto, Joao M.; Nogueira, Juliana; Osland, Michael J.; Pagès, Jordi F.; Perera, Nipuni; Pfeiffer, Eva-Maria; Pollmann, Thomas; Raw, Jacqueline L.; Recio, María; Ruiz-Fernández, Ana Carolina; Russell, Sophie K.; Rybczyk, John M.; Sammul, Marek; Sanders, Christian; Santos, Rui; Serrano, Oscar; Siewert, Matthias; Smeaton, Craig; Song, Zhaoliang; Trasar-Cepeda, Carmen; Twilley, Robert R.; Van de Broek, Marijn; Vitti, Stefano; Antisari, Livia Vittori; Voltz, Baptiste; Wails, Christy N.; Ward, Raymond D.; Ward, Melissa; Wolfe, Jaxine; Yang, Renmin; Zubrzycki, Sebastian; Landis, Emily; Smart, Lindsey; Spalding, Mark; Worthington, Thomas A.Tidal marshes store large amounts of organic carbon in their soils. Field data quantifying soil organic carbon (SOC) stocks provide an important resource for researchers, natural resource managers, and policy-makers working towards the protection, restoration, and valuation of these ecosystems. We collated a global dataset of tidal marsh soil organic carbon (MarSOC) from 99 studies that includes location, soil depth, site name, dry bulk density, SOC, and/or soil organic matter (SOM). The MarSOC dataset includes 17,454 data points from 2,329 unique locations, and 29 countries. We generated a general transfer function for the conversion of SOM to SOC. Using this data we estimated a median (+/- median absolute deviation) value of 79.2 +/- 38.1 Mg SOC ha-1 in the top 30 cm and 231 +/- 134 Mg SOC ha-1 in the top 1 m of tidal marsh soils globally. This data can serve as a basis for future work, and may contribute to incorporation of tidal marsh ecosystems into climate change mitigation and adaptation strategies and policies.
- Global seaweed productivityPublication . Pessarrodona, Albert; Assis, Jorge; Filbee-Dexter, Karen; Burrows, Michael T.; Gattuso, Jean-Pierre; Duarte, Carlos M.; Krause-Jensen, Dorte; Moore, Pippa J.; Smale, Dan A.; Wernberg, ThomasThe magnitude and distribution of net primary production (NPP) in the coastal ocean remains poorly constrained, particularly for shallow marine vegetation. Here, using a compilation of in situ annual NPP measurements across >400 sites in 72 geographic ecoregions, we provide global predictions of the productivity of seaweed habitats, which form the largest vegetated coastal biome on the planet. We find that seaweed NPP is strongly coupled to climatic variables, peaks at temperate latitudes, and is dominated by forests of large brown seaweeds. Seaweed forests exhibit exceptionally high per-area production rates (a global average of 656 and 1711 gC m-2 year-1 in the subtidal and intertidal, respectively), being up to 10 times higher than coastal phytoplankton in temperate and polar seas. Our results show that seaweed NPP is a strong driver of production in the coastal ocean and call for its integration in the oceanic carbon cycle, where it has traditionally been overlooked.
- Major expansion of marine forests in a warmer ArcticPublication . Assis, Jorge; Serrao, Ester; Duarte, Carlos M.; Fragkopoulou, Eliza; Krause-Jensen, DorteAccelerating warming and associated loss of sea ice are expected to promote the expansion of coastal marine forests (macrophytes) along the massive Arctic coastlines. Yet, this region has received much less attention compared to other global oceans. The available future projections of Arctic macrophytes are still limited to few species and regions, and mostly focused at lower latitude ranges, thus precluding well-informed IPCC impact assessments, conservation and management. Here we aim to quantify potential distributional changes of Arctic intertidal and subtidal brown macroalgae and eelgrass by the year 2100, relative to present. We estimate habitat suitability by means of species distribution modeling, considering changes in seawater temperature, salinity, nutrients and sea ice cover under two greenhouse gas emission scenarios, one consistent with the Paris Agreement (RCP 2.6) and the other representing limited mitigation strategies (RCP 8.5). As data on substrate conditions do not exist, the models were restricted to the depth range supporting Arctic macrophytes (down to 5 m for eelgrass and 30 m for brown macroalgae). Models projected major expansions of Arctic macrophytes between 69,940 and 123,360 km2, depending on the climate scenario, with polar distribution limits shifting northwards by up to 1.5 latitude degrees at 21.81 km per decade. Such expansions in response to changing climate will likely elicit major changes in biodiversity and ecosystem functions in the future Arctic. Expansions are, however, less intense than those already realized over the past century, indicating an overall slowing down despite accelerated warming as habitats become increasingly occupied..
- Recent trend reversal for declining European seagrass meadowsPublication . de los Santos, Carmen B.; Krause-Jensen, Dorte; Alcoverro, Teresa; Marbà, Nuria; Duarte, Carlos M.; Van Katwijk, Marieke; Pérez, Marta; Romero, Javier; Sánchez Lizaso, José Luis; Roca, Guillem; Jankowska, Emilia; Perez-Llorens, Jose Lucas; Fournier, Jérôme; Montefalcone, Monica; Pergent, Gérard; Ruiz, Juan M.; Cabaço, Susana; Cook, Kevan; Wilkes, Robert J.; Moy, Frithjof E.; Trayter, Gregori Muñoz-Ramos; Arañó, Xavier Seglar; Jong, Dick J. de; Fernández-Torquemada, Yolanda; Auby, Isabelle; Vergara, Juan J.; Santos, RuiSeagrass meadows, key ecosystems supporting fisheries, carbon sequestration and coastal protection, are globally threatened. In Europe, loss and recovery of seagrasses are reported, but the changes in extent and density at the continental scale remain unclear. Here we collate assessments of changes from 1869 to 2016 and show that 1/3 of European seagrass area was lost due to disease, deteriorated water quality, and coastal development, with losses peaking in the 1970s and 1980s. Since then, loss rates slowed down for most of the species and fast-growing species recovered in some locations, making the net rate of change in seagrass area experience a reversal in the 2000s, while density metrics improved or remained stable in most sites. Our results demonstrate that decline is not the generalised state among seagrasses nowadays in Europe, in contrast with global assessments, and that deceleration and reversal of declining trends is possible, expectingly bringing back the services they provide.