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Sergio Rossi - One of the best experts on this subject based on the ideXlab platform.

  • trophic ecology of caribbean octocorals autotrophic and heterotrophic seasonal trends
    Coral Reefs, 2020
    Co-Authors: Sergio Rossi, Nadine Schubert, Darren Brown, Alba Gonzalezposada, Marcelo De Oliveira Soares
    Abstract:

    Studies over the past decades indicate that octocorals are becoming the dominant group in some areas of the Caribbean. Yet, basic knowledge about the trophic ecology of these organisms and their seasonal and species-specific variability is still scarce, though this might play a key role in determining their importance in benthic–pelagic Coupling processes and, consequently, their role in carbon cycles. In the present study, two Caribbean gorgonian species (Plexaurella nutans and Pterogorgia anceps) were studied during an annual cycle, to assess seasonal variations in their reliance on heterotrophic versus autotrophic energy inputs. Zooplankton capture rates and bulk tissue stable isotopes were measured on a monthly basis to assess heterotrophic energy input, while autotrophic contribution was quantified monthly by Symbiodiniaceae cell densities and pigment contents, accompanied by seasonal measurements on Symbiodiniaceae (Breviolum sp.) photosynthetic performance and host respiratory demand. The results show that while autotrophy was the main energy source for both species, there was also a non-neglectable input through zooplankton that accounted for 0.2–0.8% and 0.7–3.4% of the energy demands in P. nutans and P. anceps, respectively. Our data further demonstrate that there are species-specific and seasonal differences in the contributions of these two nutrition modes, though there is no indication of shifts in the predominant mode during the year in either species. The energy inputs resulted in a positive energy balance throughout the year, with an energy surplus available for somatic growth, gonads, and/or energy reserves (e.g., lipids). However, the seasonal patterns differed between species, a feature that is most likely related to the different reproduction periods of the octocorals. Altogether, the information gathered here serves for a better understanding of the trophic ecology of mixotrophic octocorals and the seasonal variability of the nutritional modes that will define their potential impact in the carbon cycle and benthic–pelagic Coupling processes of coral reefs.

  • the role of mediterranean sponges in benthic pelagic Coupling processes aplysina aerophoba and axinella polypoides case studies
    Journal of Experimental Marine Biology and Ecology, 2016
    Co-Authors: Martina Coppari, Andrea Gori, Nuria Viladrich, Luca Saponari, Antonio Canepa, Jordi Grinyo, Alejandro Olariaga, Sergio Rossi
    Abstract:

    Abstract Sponges are important components of marine benthic communities with a worldwide distribution ranging from polar to tropical regions. They play a key role in benthic–pelagic Coupling processes through their active suspension feeding, providing a trophic link between the benthos and the overlying water column. Little is known about their broad-scale distribution and feeding ecology. The general tendency is to quantify their trophic impact through small patch estimations. In this work, two of the most abundant sponges in Mediterranean coastal bottoms ( Aplysina aerophoba and Axinella polypoides ) were studied combining remotely operated vehicle (ROV) survey with in situ feeding experiments. Spatial, bathymetrical distribution and population size structure of these species were analysed, together with their trophic ecology, in spring and autumn. We found that A. aerophoba is distributed between 5 and 20 m depth, with maximum densities of 1.6 sponges m − 2 . This species ingested 0.12–0.39 mg of carbon (C) g AFDW − 1 (ash free dry weight) day − 1 in spring and 0.09–0.13 mg C g AFDW − 1  day − 1 in autumn. Conversely, A. polypoides was found between 10 and 70 m depth, with maximum densities of 7.6 sponges m − 2 . This species ingested 0.07–0.17 mg C g AFDW − 1  day − 1 in spring, and 0.18–0.60 mg C g AFDW − 1  day − 1 in autumn. The highest uptake of C concentrated between 5 and 15 m depth for A. aerophoba and between 65 and 70 m depth for A. polypoides . In the 1.14 ha of studied coastal bottom, A. aerophoba ingested 1.87 g C during spring and 0.19 g C during autumn, whereas A. polypoides 13.60 g C and 29.36 g C during spring and autumn, respectively. The present approach allowed a spatially explicit quantification of benthic–pelagic Coupling processes produced by two of the most common sponges in a Mediterranean coastal area. This methodology, applied to benthic communities, mirrors similar approaches used in terrestrial forestry studies for C flux estimation.

  • size spatial and bathymetrical distribution of the ascidian halocynthia papillosa in mediterranean coastal bottoms benthic pelagic Coupling implications
    Marine Biology, 2014
    Co-Authors: Martina Coppari, Sergio Rossi, Andrea Gori
    Abstract:

    Benthic suspension feeders are abundant in Mediterranean coastal environments, though most of them are threatened due to overexploitation, climate change impacts, and unregulated diving or fishing practices. Little is known about most of the coastal communities in terms of large-scale distribution and realistic benthic–pelagic Coupling implications, which are keys to understand and manage those threatened ecosystems. The active suspension feeder Halocynthia papillosa (one of the most common ascidian species of the Mediterranean Sea) was selected as a model organism to help to understand the ecological role in benthic–pelagic Coupling processes and its importance as a carbon sink (an essential ecosystem service). The spatial and bathymetrical distribution of this organism has been studied using remotely operated vehicle video transects. The species was distributed throughout the study area, with a maximum density of 4 specimens m−2. The highest abundances and the biggest sizes were observed on the range of 20–50 m depth. The role as carbon and nitrogen sink of this suspension feeder has been quantified Coupling distribution data with existing in situ studies of feeding and respiration. Along the 1.24 ha of the study area, H. papillosa yearly ingested 519.4 g C and 31.4 g N and retained 20.2 g C. As long as the physiological data are known, this new methodology could be very useful in assessing bentho–pelagic links and the capacity of being C and N sinks of a wide range of species. This new approach may be essential for the future management of benthic communities.

Inna M Sokolova - One of the best experts on this subject based on the ideXlab platform.

  • interactive effects of osmotic stress and burrowing activity on protein metabolism and muscle capacity in the soft shell clam mya arenaria
    Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2019
    Co-Authors: Fouzia Haider, Eugene P Sokolov, Stefan Timm, Martin Hagemann, Esther Blanco Rayon, Ionan Marigomez, Urtzi Izagirre, Inna M Sokolova
    Abstract:

    Abstract Bioturbators such as sediment-dwelling marine bivalves are ecosystem engineers that enhance sediment-water exchange and Benthic-Pelagic Coupling. In shallow coastal areas, bivalves are exposed to frequent disturbance and salinity stress that might negatively affect their activity and physiological performance; however, the mechanisms underlying these effects are not fully understood. We investigated the effects of osmotic stress (low and fluctuating salinity) and repeated burrowing on aerobic and contractile capacity of the foot muscle (assessed by the activity of succinate dehydrogenase and myosin ATPase) as well as the levels of organic osmolytes (free amino acids) and biochemical markers of protein synthesis and proteolysis in key osmoregulatory and energy storing tissues (gills and hepatopancreas, respectively) in a common bioturbator, the soft shell clam Mya arenaria. Osmotic stress and exhaustive exercise altered the foot muscle capacity of soft shell clams and had a strong impact on protein and amino acid homeostasis in tissues not directly involved in locomotion. Acclimation to constant low salinity (5 practical salinity units) depleted the whole-body free amino acid pool and affected protein synthesis but not protein breakdown in the gill. In contrast, fluctuating (5–15) salinity increased protein breakdown rate, suppressed protein synthesis, caused oxidative damage to proteins in the gill and selectively depleted whole-body glycine pool. Clams acclimated to normal salinity (15) increased the aerobic capacity of the foot muscle upon repeated burrowing, whereas acclimation to low and fluctuating salinity reduced this adaptive muscle plasticity. Under the normal and low salinity conditions, exhaustive exercise induced protein conservation pathways (indicated by suppression of protein synthesis and catabolism), but this effect was disrupted by fluctuating salinity. These findings indicate that exhaustive exercise and osmotic stress interactively affect whole-body protein homeostasis and functional capacity of the foot muscle in soft shell clams which might contribute to reduced burrowing activity of bivalve bioturbators in osmotically challenging environments such as estuaries and shallow coastal zones.

Eugene P Sokolov - One of the best experts on this subject based on the ideXlab platform.

  • interactive effects of osmotic stress and burrowing activity on protein metabolism and muscle capacity in the soft shell clam mya arenaria
    Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2019
    Co-Authors: Fouzia Haider, Eugene P Sokolov, Stefan Timm, Martin Hagemann, Esther Blanco Rayon, Ionan Marigomez, Urtzi Izagirre, Inna M Sokolova
    Abstract:

    Abstract Bioturbators such as sediment-dwelling marine bivalves are ecosystem engineers that enhance sediment-water exchange and Benthic-Pelagic Coupling. In shallow coastal areas, bivalves are exposed to frequent disturbance and salinity stress that might negatively affect their activity and physiological performance; however, the mechanisms underlying these effects are not fully understood. We investigated the effects of osmotic stress (low and fluctuating salinity) and repeated burrowing on aerobic and contractile capacity of the foot muscle (assessed by the activity of succinate dehydrogenase and myosin ATPase) as well as the levels of organic osmolytes (free amino acids) and biochemical markers of protein synthesis and proteolysis in key osmoregulatory and energy storing tissues (gills and hepatopancreas, respectively) in a common bioturbator, the soft shell clam Mya arenaria. Osmotic stress and exhaustive exercise altered the foot muscle capacity of soft shell clams and had a strong impact on protein and amino acid homeostasis in tissues not directly involved in locomotion. Acclimation to constant low salinity (5 practical salinity units) depleted the whole-body free amino acid pool and affected protein synthesis but not protein breakdown in the gill. In contrast, fluctuating (5–15) salinity increased protein breakdown rate, suppressed protein synthesis, caused oxidative damage to proteins in the gill and selectively depleted whole-body glycine pool. Clams acclimated to normal salinity (15) increased the aerobic capacity of the foot muscle upon repeated burrowing, whereas acclimation to low and fluctuating salinity reduced this adaptive muscle plasticity. Under the normal and low salinity conditions, exhaustive exercise induced protein conservation pathways (indicated by suppression of protein synthesis and catabolism), but this effect was disrupted by fluctuating salinity. These findings indicate that exhaustive exercise and osmotic stress interactively affect whole-body protein homeostasis and functional capacity of the foot muscle in soft shell clams which might contribute to reduced burrowing activity of bivalve bioturbators in osmotically challenging environments such as estuaries and shallow coastal zones.

Jasmin A Godbold - One of the best experts on this subject based on the ideXlab platform.

  • climate driven benthic invertebrate activity and biogeochemical functioning across the barents sea polar front
    Philosophical Transactions of the Royal Society A, 2020
    Co-Authors: Martin Solan, Ellie R Ward, Christina L Wood, Adam J Reed, Laura J Grange, Jasmin A Godbold
    Abstract:

    Arctic marine ecosystems are undergoing rapid correction in response to multiple expressions of climate change, but the consequences of altered biodiversity for the sequestration, transformation and storage of nutrients are poorly constrained. Here, we determine the bioturbation activity of sediment-dwelling invertebrate communities over two consecutive summers that contrasted in sea-ice extent along a transect intersecting the polar front. We find a clear separation in community composition at the polar front that marks a transition in the type and amount of bioturbation activity, and associated nutrient concentrations, sufficient to distinguish a southern high from a northern low. While patterns in community structure reflect proximity to arctic versus boreal conditions, our observations strongly suggest that faunal activity is moderated by seasonal variations in sea ice extent that influence food supply to the benthos. Our observations help visualize how a climate-driven reorganization of the Barents Sea benthic ecosystem may be expressed, and emphasize the rapidity with which an entire region could experience a functional transformation. As strong Benthic-Pelagic Coupling is typical across most parts of the Arctic shelf, the response of these ecosystems to a changing climate will have important ramifications for ecosystem functioning and the trophic structure of the entire food web. This article is part of the theme issue 'The changing Arctic Ocean: consequences for biological communities, biogeochemical processes and ecosystem functioning'.

Rossi Sergio - One of the best experts on this subject based on the ideXlab platform.

  • Polyp expansion of passive suspension feeders : A red coral case study
    'PeerJ', 2019
    Co-Authors: Rossi Sergio, Rizzo Lucia, Duchêne Jean-claude
    Abstract:

    Unidad de excelencia María de Maeztu MdM-2015-0552Polyp activity in passive suspension feeders has been considered to be affected by several environmental factors such as hydrodynamics, water temperature and food concentration. To better elucidate the driving forces controlling polyp expansion in these organisms and the potential role of particle concentration, the octocoral Corallium rubrum was investigated in accordance with two approaches: (1) high-frequency in- situ observations examining various environmental and biological variables affecting the water column, and (2) video-recorded flume-controlled laboratory experiments performed under a range of environmental and biological conditions, in terms of water temperature, flow speed, chemical signals and zooplankton. In the field, C. rubrum polyp expansion correlated positively with particle (seston and zooplankton) concentration and current speed. This observation was confirmed by the flume video records of the laboratory experiments, which showed differences in polyp activity due to changes in temperature and current speed, but especially in response to increasing nutritional stimuli. The maximum activity was observed at the highest level of nutritional stimulus consisting of zooplankton. Zooplankton and water movement appeared to be the main factors controlling polyp expansion. These results suggest that the energy budget of passive suspension feeders (and probably the benthic community as a whole) may rely on their ability to maximise prey capture during food pulses. The latter, which may be described as discontinuous organic matter (dead or alive) input, may be the key to a better understanding of Benthic-Pelagic Coupling processes and trophic impacts on animal forests composed of sessile suspension feeders

  • The importance of coastal gorgonians in the blue carbon budget
    'Springer Science and Business Media LLC', 2019
    Co-Authors: Coppari Martina, Zanella Chiara, Rossi Sergio
    Abstract:

    Unidad de excelencia María de Maeztu MdM-2015-0552Terrestrial (trees, shrubs) and marine (seaweeds and seagrasses) organisms act as carbon (C) sinks, but the role of benthic suspension feeders in this regard has been largely neglected so far. Gorgonians are one of the most conspicuous inhabitants of marine animal forests (mainly composed of sessile filter feeders); their seston capture rates influence Benthic-Pelagic Coupling processes and they act as C sinks immobilizing carbon in their long-living structures. Three gorgonian species (Paramuricea clavata, Eunicella singularis and Leptogorgia sarmentosa) were studied Coupling data of population size structure, biomass and spatial distribution in a NW Mediterranean area (Cap de Creus, Spain) with feeding, respiration and growth rates. In the study area, we calculated that P. clavata sequestered 0.73 ± 0.71 g C m year, E. singularis 0.73 ± 0.89 g C m year and L. sarmentosa 0.03 ± 0.02 g C m year. To our knowledge, this is the first attempt to calculate the importance as C sinks of gorgonian species that we consider as a starting point to estimate the importance of marine animal forests in C sequestration, and to ensure appropriate management and protection especially in areas and at depths where they are concentrated

  • The importance of coastal gorgonians in the blue carbon budget
    'Springer Science and Business Media LLC', 2019
    Co-Authors: Coppari Martina, Zanella Chiara, Rossi Sergio
    Abstract:

    12 pages, 3 figures, 3 tables, supporting information https://doi.org/10.1038/s41598-019-49797-4Terrestrial (trees, shrubs) and marine (seaweeds and seagrasses) organisms act as carbon (C) sinks, but the role of benthic suspension feeders in this regard has been largely neglected so far. Gorgonians are one of the most conspicuous inhabitants of marine animal forests (mainly composed of sessile filter feeders); their seston capture rates influence Benthic-Pelagic Coupling processes and they act as C sinks immobilizing carbon in their long-living structures. Three gorgonian species (Paramuricea clavata, Eunicella singularis and Leptogorgia sarmentosa) were studied Coupling data of population size structure, biomass and spatial distribution in a NW Mediterranean area (Cap de Creus, Spain) with feeding, respiration and growth rates. In the study area, we calculated that P. clavata sequestered 0.73 ± 0.71 g C m−2 year−1, E. singularis 0.73 ± 0.89 g C m−2 year−1 and L. sarmentosa 0.03 ± 0.02 g C m−2 year−1. To our knowledge, this is the first attempt to calculate the importance as C sinks of gorgonian species that we consider as a starting point to estimate the importance of marine animal forests in C sequestration, and to ensure appropriate management and protection especially in areas and at depths where they are concentratedC was funded by a FI AGAUR research grant (2012_FI_B00752), CZ was funded by the Erasmus Placement fellowship, SR was funded by a Marie Curie International Outgoing Fellowship (ANIMAL FOREST HEALTH, Grant Agreement Number 327845) and assistance from P-SPHERE (COFUND Marie Curie, Grant Agreement Number 665919). The authors thank the Generalitat de Catalunya (MERS) for their support (2017 SGR - 1588)Peer Reviewe

  • The role of Mediterranean sponges in Benthic-Pelagic Coupling processes: Aplysina aerophoba and Axinella polypoides case studies
    'Elsevier BV', 2016
    Co-Authors: Coppari Martina, Gori Andrea, Viladrich Nuria, Saponari Luca, Canepa Antonio, Grinyó Jordi, Olariaga Alejandro, Rossi Sergio
    Abstract:

    12 pages, 10 figures, 4 tables, supplementary data http://dx.doi.org/10.1016/j.jembe.2016.01.004Sponges are important components of marine benthic communities with a worldwide distribution ranging from polar to tropical regions. They play a key role in benthic–pelagic Coupling processes through their active suspension feeding, providing a trophic link between the benthos and the overlying water column. Little is known about their broad-scale distribution and feeding ecology. The general tendency is to quantify their trophic impact through small patch estimations. In this work, two of the most abundant sponges in Mediterranean coastal bottoms (Aplysina aerophoba and Axinella polypoides) were studied combining remotely operated vehicle (ROV) survey with in situ feeding experiments. Spatial, bathymetrical distribution and population size structure of these species were analysed, together with their trophic ecology, in spring and autumn. We found that A. aerophoba is distributed between 5 and 20 m depth, with maximum densities of 1.6 sponges m− 2. This species ingested 0.12–0.39 mg of carbon (C) g AFDW− 1 (ash free dry weight) day− 1 in spring and 0.09–0.13 mg C g AFDW− 1 day− 1 in autumn. Conversely, A. polypoides was found between 10 and 70 m depth, with maximum densities of 7.6 sponges m− 2. This species ingested 0.07–0.17 mg C g AFDW− 1 day− 1 in spring, and 0.18–0.60 mg C g AFDW− 1 day− 1 in autumn. The highest uptake of C concentrated between 5 and 15 m depth for A. aerophoba and between 65 and 70 m depth for A. polypoides. In the 1.14 ha of studied coastal bottom, A. aerophoba ingested 1.87 g C during spring and 0.19 g C during autumn, whereas A. polypoides 13.60 g C and 29.36 g C during spring and autumn, respectively. The present approach allowed a spatially explicit quantification of benthic–pelagic Coupling processes produced by two of the most common sponges in a Mediterranean coastal area. This methodology, applied to benthic communities, mirrors similar approaches used in terrestrial forestry studies for C flux estimationMC was funded by a FI AGAUR research grant (2012_FI_B00752), and SR was funded by a Ramón y Cajal Contract (RyC-2007-01327) and a Marie Curie International Outgoing Fellowship (ANIMAL FOREST HEALTH, Grant Agreement Number 327845). Authors want to thank the support of the Generalitat de Catalunya to MERS (2014 SGR-1356). This work was supported by the BENTOLARV project (CTM2009-10007)Peer Reviewe