Browsing by Author "Kamenos, Nicholas A."
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- Contribution of the seagrass Syringodium isoetifolium to the metabolic functioning of a tropical reef lagoonPublication . Olivé, Irene; García-Robledo, Emilio; Silva, João; Pintado-Herrera, Marina G.; Santos, Rui; Kamenos, Nicholas A.; Cuet, Pascale; Frouin, PatrickSeagrasses are gaining attention thanks to their metabolism and potential major role as carbon sinks, with further implications as nature-based solutions against climate change. Despite their recognized importance and the growing number of studies published, there is still a striking paucity of information on seagrass metabolism and contribution to biogeochemical cycles for some seagrass species and ocean areas. In this study we assessed the metabolic balance and nutrient cycling contribution of seagrasses to the benthic compartment of a tropical reef lagoon in Reunion Island, providing original information on a barely studied seagrass species (Syringodium isoetifolium) and a poorly studied ocean region (West Indian Ocean). We measured the net productivity, respiration and the metabolic balance in different components of the lagoon benthic compartment (i.e. seagrass, sediment, and benthic community) and the water-sediment nutrient benthic fluxes at differently impacted sites within the lagoon. The biogeochemical environmental variability, including inorganic and organic indicators of anthropogenic contamination, was also assessed at each site.Large spatial variability was detected in the metabolic balance of each benthic component assessed, also associated with the natural and/or anthropic-driven environmental variability found in the lagoon. The seagrass S. isoetifolium was net autotrophic across the lagoon and contributed to the lagoon benthic metabolism with net plant productivity exceeding by one order of magnitude the plant respiration. The lowest seagrass metabolism was detected at the impacted site. The metabolic balance of the sediment was heterotrophic but the high productivity of S. isoetifolium contributed to reducing the heterotrophy of the whole benthic community. The lagoon-wide benthic metabolic balance was slightly heterotrophic, but the associated uncertainty ranged from autotrophy to heterotrophy. Nutrient concentrations in the lagoon were low and the benthic community capacity for nutrient retention (uptake) and removal (denitrification and anammox) indicated potential for buffering moderate nutrient inputs into the lagoon. Organic contaminants of emerging concern (CECs) were low but detectable in the lagoon, especially in highly frequented beach areas, arising as an environmental quality indicator of interest.
- Editorial: coralline algae: globally distributed ecosystem engineersPublication . Schubert, Nadine; Schoenrock, Kathryn M.; Aguirre, Julio; Kamenos, Nicholas A.; Silva, João; Horta, Paulo A.; Hofmann, Laurie C.From the early days of phycology, coralline algae (CA) have been considered the most formidable and widely distributed algae (Woelkerling, 1988). They compose an abundant and highly diverse group, divided into geniculate (articulated) and non-geniculate species (crusts and rhodolith/maërl forms). CA are present in almost every coastal ecosystem around the world, from the intertidal to mesophotic zones (Johansen et al., 1981; Steneck, 1986; Foster, 2001). They are important ecosystem engineers that provide hard, three-dimensional substrates for a highly diverse fauna and flora (Nelson, 2009), building habitats like the globally distributed rhodolith (or maërl) beds (Foster, 2001), and the large algal bioconstructions that abound in the Mediterranean (coralligenous assemblages, intertidal rims; Ingrosso et al., 2018). In addition, the CaCO3 precipitation within cell walls leads to a high fossilization potential of CA, which are considered the best fossil record among macrobenthic autotrophs since they first appeared in the Lower Cretaceous (Aguirre et al., 2000). It also makes CA major carbonate producers (van der Heijden and Kamenos, 2015), which, considering their abundance and wide distribution, gives them an important role in oceanic carbon cycling and reef building (Adey, 1998; Chisholm, 2003; Martin et al., 2006; Perry et al., 2008) and makes them a group of significant economic interest (Coletti and Frixa, 2017). Like many other marine ecosystems, CA habitats will be negatively affected by future climate change, e.g., due to reduced CA calcification/growth (Martin andHall-Spencer, 2017; Cornwall et al., 2019) that may eventually lead to ecosystem degradation and reduction of habitat complexity and biodiversity.
- Editorial: Coralline algae: Past, present, and future perspectivesPublication . Hofmann, Laurie C.; Schoenrock, Kathryn M.; Kamenos, Nicholas A.; Aguirre, Julio; Silva, João; Schubert, NadineFollowing the success of the Frontiers in Marine Science Research Topic on “Coralline Algae: Globally Distributed Ecosystem Engineers,” the Research Topic on “Coralline Algae: Past, Present and Future Perspectives” was launched to extend the opportunity for publishing further knowledge about these diverse ecosystem engineers across a broader time scale. In this Research Topic, an additional nine original research articles have been published, strengthening our understanding of coralline algae past, present, and future, including their biology, physiology and ecology. From reconstructing coralline algal assemblages during the Paleocene/Eocene thermal maximum, to understanding current trophodynamics and benthic-pelagic coupling in rhodolith beds, to assessing the adaptability of coralline algae to future warming, the original research articles in this Research Topic cover a time frame of 55.6 million years and span across an Atlantic biogeographical range from Brazil to the high Arctic.
- Levelling-up rhodolith-bed science to address global-scale conservation challengesPublication . Tuya, Fernando; Schubert, Nadine; Aguirre, Julio; Basso, Daniela; Bastos, Eduardo O.; Berchez, Flávio; Bernardino, Angelo F.; Bosch, Néstor E.; Burdett, Heidi L.; Espino, Fernando; Fernández-Gárcia, Cindy; Francini-Filho, Ronaldo B.; Gagnon, Patrick; Hall-Spencer, Jason M.; Haroun, Ricardo; Hofmann, Laurie C.; Horta, Paulo A.; Kamenos, Nicholas A.; Le Gall, Line; Magris, Rafael A.; Martin, Sophie; Nelson, Wendy A.; Neves, Pedro; Olivé, Irene; Otero-Ferrer, Francisco; Peña, Viviana; Pereira-Filho, Guilherme H.; Ragazzola, Federica; Rebelo, Ana Cristina; Ribeiro, Cláudia; Rinde, Eli; Schoenrock, Kathryn; Silva, João; Sissini, Marina N.; Tâmega, Frederico T. S.Global marine conservation remains fractured by an imbalance in research efforts and policy actions, limiting progression towards sustainability. Rhodolith beds represent a prime example, as they have ecological importance on a global scale, provide a wealth of ecosystem functions and services, including biodiversity provision and potential climate change mit-igation, but remain disproportionately understudied, compared to other coastal ecosystems (tropical coral reefs, kelp for-ests, mangroves, seagrasses). Although rhodolith beds have gained some recognition, as important and sensitive habitats at national/regional levels during the last decade, there is still a notable lack of information and, consequently, specific conservation efforts. We argue that the lack of information about these habitats, and the significant ecosystem services they provide, is hindering the development of effective conservation measures and limiting wider marine conservation success. This is becoming a pressing issue, considering the multiple severe pressures and threats these habitats are exposed to (e.g., pollution, fishing activities, climate change), which may lead to an erosion of their ecological function and eco-system services. By synthesizing the current knowledge, we provide arguments to highlight the importance and urgency of levelling-up research efforts focused on rhodolith beds, combating rhodolith bed degradation and avoiding the loss of associated biodiversity, thus ensuring the sustainability of future conservation programs.
- Positive species interactions structure rhodolith bed communities at a global scalePublication . Bulleri, Fabio; Schubert, Nadine; Hall‐Spencer, Jason M.; Basso, Daniela; Burdett, Heidi L.; Francini‐Filho, Ronaldo B.; Grall, Jacques; Horta, Paulo A.; Kamenos, Nicholas A.; Martin, Sophie; Nannini, Matteo; Neves, Pedro António Nobre Soares Pinto das; Olivé, Irene; Peña, Viviana; Ragazzola, Federica; Ribeiro, Cláudia; Rinde, Eli; Sissini, Marina; Tuya, Fernando; Silva, JoãoRhodolith beds are diverse and globally distributed habitats. Nonetheless, the role of rhodoliths in structuring the associated species community through a hierarchy of positive interactions is yet to be recognised. In this review, we provide evidence that rhodoliths can function as foundation species of multi-level facilitation cascades and, hence, are fundamental for the persistence of hierarchically structured communities within coastal oceans. Rhodoliths generate facilitation cascades by buffering physical stress, reducing consumer pressure and enhancing resource availability. Due to large variations in their shape, size and density, a single rhodolith bed can support multiple taxonomically distant and architecturally distinct habitat-forming species, such as primary producers, sponges or bivalves, thus encompassing a broad range of functional traits and providing a wealth of secondary microhabitat and food resources. In addition, rhodoliths are often mobile, and thus can redistribute associated species, potentially expanding the distribution of species with short-distance dispersal abilities. Key knowledge gaps we have identified include: the experimental assessment of the role of rhodoliths as basal facilitators; the length and temporal stability of facilitation cascades; variations in species interactions within cascades across environmental gradients; and the role of rhodolith beds as climate refugia. Addressing these research priorities will allow the development of evidence-based policy decisions and elevate rhodolith beds within marine conservation strategies.
- The future of the northeast Atlantic benthic flora in a high CO2 worldPublication . Brodie, Juliet; Williamson, Christopher J.; Smale, Dan A.; Kamenos, Nicholas A.; Mieszkowska, Nova; Santos, Rui; Cunliffe, Michael; Steinke, Michael; Yesson, Christopher; Anderson, Kathryn M.; Asnaghi, Valentina; Brownlee, Colin; Burdett, Heidi L.; Burrows, Michael T.; Collins, Sinead; Donohue, Penelope J. C.; Harvey, Ben; Foggo, Andrew; Noisette, Fanny; Nunes, Joana; Ragazzola, Federica; Raven, John A.; Schmidt, Daniela N.; Suggett, David; Teichberg, Mirta; Hall-Spencer, JasonSeaweed and seagrass communities in the northeast Atlantic have been profoundly impacted by humans, and the rate of change is accelerating rapidly due to runaway CO2 emissions and mounting pressures on coastlines associated with human population growth and increased consumption of finite resources. Here, we predict how rapid warming and acidification are likely to affect benthic flora and coastal ecosystems of the northeast Atlantic in this century, based on global evidence from the literature as interpreted by the collective knowledge of the authorship. We predict that warming will kill off kelp forests in the south and that ocean acidification will remove maerl habitat in the north. Seagrasses will proliferate, and associated epiphytes switch from calcified algae to diatoms and filamentous species. Invasive species will thrive in niches liberated by loss of native species and spread via exponential development of artificial marine structures. Combined impacts of seawater warming, ocean acidification, and increased storminess may replace structurally diverse seaweed canopies, with associated calcified and noncalcified flora, with simple habitats dominated by noncalcified, turf-forming seaweeds.