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Marco Abbiati - One of the best experts on this subject based on the ideXlab platform.

  • Spatial–temporal variability of epibenthic assemblages on subtidal biogenic reefs in the northern Adriatic Sea
    Marine Biology, 2011
    Co-Authors: Massimo Ponti, Federica Fava, Marco Abbiati
    Abstract:

    Spatial distribution and temporal variation of epibenthic assemblages of coralligenous biogenic rocky outcrops occurring in the northern Adriatic Sea (45°04′–45°24′N; 12°23′–12°43′E) were investigated by photographic sampling from 2003 to 2006 at 12 randomly selected sites. The dominant reef-forming organisms were the encrusting calcareous algae ( Lithophyllum stictaeforme , Lithothamnion minervae and Peyssonnelia polymorpha ), while the main bioeroders were boring sponges ( Cliona viridis , C. celata , C. thoosina , C. rhodensis , Piona vastifica ) and the bivalve Gastrochaena dubia . Composition of the assemblages varied thorough years and among sites. Spatial heterogeneity, at local and regional scale, prevailed over temporal variation. This variability was related both to the geo-morphological features of the outcrops and to environmental variables. Sites clearly differed in the percent cover of reef builder and bioeroder species while only limited temporal variation within site was found. Some taxa revealed complex intra-site temporal trends. These results provide valuable information on the diversity and variability of epibenthic assemblages of the northern Adriatic coralligenous reefs, essential for the management and conservation of these unique biogenic habitats.

  • Spatial-temporal variability of epibenthic assemblages on subtidal biogenic reefs in the northern Adriatic Sea
    Marine Biology, 2011
    Co-Authors: Massimo Ponti, Federica Fava, Marco Abbiati
    Abstract:

    Spatial distribution and temporal variation of epibenthic assemblages of coralligenous biogenic rocky outcrops occurring in the northern Adriatic Sea (45°04′–45°24′N; 12°23′–12°43′E) were investigated by photographic sampling from 2003 to 2006 at 12 randomly selected sites. The dominant reef-forming organisms were the encrusting calcareous algae (Lithophyllum stictaeforme, Lithothamnion minervae and Peyssonnelia polymorpha), while the main bioeroders were boring sponges (Cliona viridis, C. celata, C. thoosina, C. rhodensis, Piona vastifica) and the bivalve Gastrochaena dubia. Composition of the assemblages varied thorough years and among sites. Spatial heterogeneity, at local and regional scale, prevailed over temporal variation. This variability was related both to the geo-morphological features of the outcrops and to environmental variables. Sites clearly differed in the percent cover of reef builder and bioeroder species while only limited temporal variation within site was found. Some taxa revealed complex intra-site temporal trends. These results provide valuable information on the diversity and variability of epibenthic assemblages of the northern Adriatic coralligenous reefs, essential for the management and conservation of these unique biogenic habitats.

  • Spatial and temporal variations of assemblages in a Mediterranean coralligenous reef and relationships with surface orientation
    Coral Reefs, 2006
    Co-Authors: Massimiliano Virgilio, Laura Airoldi, Marco Abbiati
    Abstract:

    The structure, distribution, and temporal changes of epibenthic assemblages of a Mediterranean coralligenous reef were investigated using a multifactorial sampling design. The distribution of taxa on vertical walls and down-facing surfaces of overhangs and crevices was analysed at ten sites along 2 km of rocky reefs, south of Livorno (Ligurian Sea, Italy). The temporal variations were analysed between two periods (1995–1996 and 1997–1998) and among four sampling times within each period. Most of the space was dominated by prostrate seaweeds (including Peyssonnelia rubra , P. rosa-marina , and Mesophyllum lichenoides ), turf-forming seaweeds, and the red coral Corallium rubrum . The cover of a variety of other invertebrates, mainly sponges and bryozoans, was less than 2%. All taxa were found on both vertical and down-facing surfaces. However, seaweeds dominated the vertical surfaces (mean cover >97%), while C. rubrum and other invertebrates dominated down-facing surfaces (mean density of C. rubrum >16 colonies dm^−2). Although there was some fluctuation in the abundance of taxa, no obvious patterns were observed. These results support the model of limited temporal variability in Mediterranean coralligenous reefs, possibly related to the slow growth rates of the most abundant taxa and the reduced seasonality of physical conditions.

Massimo Ponti - One of the best experts on this subject based on the ideXlab platform.

  • Spatial–temporal variability of epibenthic assemblages on subtidal biogenic reefs in the northern Adriatic Sea
    Marine Biology, 2011
    Co-Authors: Massimo Ponti, Federica Fava, Marco Abbiati
    Abstract:

    Spatial distribution and temporal variation of epibenthic assemblages of coralligenous biogenic rocky outcrops occurring in the northern Adriatic Sea (45°04′–45°24′N; 12°23′–12°43′E) were investigated by photographic sampling from 2003 to 2006 at 12 randomly selected sites. The dominant reef-forming organisms were the encrusting calcareous algae ( Lithophyllum stictaeforme , Lithothamnion minervae and Peyssonnelia polymorpha ), while the main bioeroders were boring sponges ( Cliona viridis , C. celata , C. thoosina , C. rhodensis , Piona vastifica ) and the bivalve Gastrochaena dubia . Composition of the assemblages varied thorough years and among sites. Spatial heterogeneity, at local and regional scale, prevailed over temporal variation. This variability was related both to the geo-morphological features of the outcrops and to environmental variables. Sites clearly differed in the percent cover of reef builder and bioeroder species while only limited temporal variation within site was found. Some taxa revealed complex intra-site temporal trends. These results provide valuable information on the diversity and variability of epibenthic assemblages of the northern Adriatic coralligenous reefs, essential for the management and conservation of these unique biogenic habitats.

  • Spatial-temporal variability of epibenthic assemblages on subtidal biogenic reefs in the northern Adriatic Sea
    Marine Biology, 2011
    Co-Authors: Massimo Ponti, Federica Fava, Marco Abbiati
    Abstract:

    Spatial distribution and temporal variation of epibenthic assemblages of coralligenous biogenic rocky outcrops occurring in the northern Adriatic Sea (45°04′–45°24′N; 12°23′–12°43′E) were investigated by photographic sampling from 2003 to 2006 at 12 randomly selected sites. The dominant reef-forming organisms were the encrusting calcareous algae (Lithophyllum stictaeforme, Lithothamnion minervae and Peyssonnelia polymorpha), while the main bioeroders were boring sponges (Cliona viridis, C. celata, C. thoosina, C. rhodensis, Piona vastifica) and the bivalve Gastrochaena dubia. Composition of the assemblages varied thorough years and among sites. Spatial heterogeneity, at local and regional scale, prevailed over temporal variation. This variability was related both to the geo-morphological features of the outcrops and to environmental variables. Sites clearly differed in the percent cover of reef builder and bioeroder species while only limited temporal variation within site was found. Some taxa revealed complex intra-site temporal trends. These results provide valuable information on the diversity and variability of epibenthic assemblages of the northern Adriatic coralligenous reefs, essential for the management and conservation of these unique biogenic habitats.

Enric Ballesteros - One of the best experts on this subject based on the ideXlab platform.

  • DOI 10.1515/bot-2012-0113   Botanica Marina 2012; 55(5): 485–497
    2016
    Co-Authors: Sergi Joher, Enric Ballesteros, Emma Cebrian, Conxi Rodr Í Guez-prieto
    Abstract:

    Deep-water macroalgal-dominated coastal detritic assemblages on the continental shelf off Mallorca and Menorca (Balearic Islands, Western Mediterranean) Abstract: We present a quantitative physiognomic charac-terization of major macroalgal-dominated assemblages on coastal detritic bottoms of the continental shelf off Mal-lorca and Menorca (Balearic Islands, Western Mediterra-nean). In late spring of 2007 and 2008, 29 samples were collected by bottom trawling at depths between-52 and-93 m. These samples were then sorted and identified to their lowest taxonomic level. Statistical analyses distin-guished six different assemblage types: shallower water environments (-52 to-65 m in depth) were characterized by Osmundaria volubilis and Phyllophora crispa meadows and two types of Peyssonnelia beds; two assemblage types, Laminaria rodriguezii beds and ma ë rl beds, were only present in deep-water environments (-77 to-81 m); and an assemblage dominated by P. crispa and Halopteris filicina was found in both shallow and deep waters (-57 to-93 m). We assess the distribution of these six assemblage types through the studied area

  • RESEARCH ARTICLE Calcareous Bio-Concretions in the Northern Adriatic Sea: Habitat Types, Environmental Factors that Influence Habitat Distributions, and Predictive Modeling
    2016
    Co-Authors: Annalisa Falace, Enric Ballesteros, Sara Kaleb, Daniele Curiel, Chiara Miotti, Giovanni Galli, Stefano Querin, Cosimo Solidoro, Vinko B
    Abstract:

    Habitat classifications provide guidelines for mapping and comparing marine resources across geographic regions. Calcareous bio-concretions and their associated biota have not been exhaustively categorized. Furthermore, for management and conservation purposes, species and habitat mapping is critical. Recently, several developments have occurred in the field of predictive habitat modeling, and multiple methods are available. In this study, we defined the habitats constituting northern Adriatic biogenic reefs and created a predictive habitat distribution model. We used an updated dataset of the epibenthic assemblages to define the habitats, which we verified using the fuzzy k-means (FKM) clustering method. Redundancy analysis was employed to model the relationships between the environmental descriptors and the FKMmembership grades. Predictive modelling was carried out to map habitats across the basin. Habitat A (opportunistic macroalgae, encrusting Porifera, bioero-ders) characterizes reefs closest to the coastline, which are affected by coastal currents and river inputs. Habitat B is distinguished by massive Porifera, erect Tunicata, and non-calcareous encrusting algae (Peyssonnelia spp.). Habitat C (non-articulated coralline, Poly

  • Contribution to the study of deep coastal detritic bottoms: the algal communities of the continental shelf off the Balearic Islands, Western Mediterranean
    Mediterranean Marine Science, 2015
    Co-Authors: S. Joher, Enric Ballesteros, C. Rodrigues-prieto
    Abstract:

    Three main algal-dominated coastal detritic communities from the continental shelf off Mallorca and Menorca (Balearic Islands, Western Mediterranean) are described herein: maerl beds dominated by Spongites fruticulosus and forests of Laminaria rodriguezii located in the Menorca channel, and Peyssonnelia inamoena beds found along the Southern coast of Menorca. There seems to be a gradient of disturbance from the highly disturbed Peyssonnelia beds to the almost undisturbed L. rodriguezii forests. Whether this gradient is the result of current and past anthropogenic pressure (e.g. trawling intensity) or is driven by natural environmental factors needs further assessment. Finally, the location of the target communities by means of ROV dives combined with the use of a Box-Corer dredge and beam trawl proved to be a good methodology in the study of the composition and structure of these deep water detritic communities.

  • Deep-water macroalgal-dominated coastal detritic assemblages on the continental shelf off Mallorca and Menorca (Balearic Islands, Western Mediterranean)
    Botanica Marina, 2012
    Co-Authors: Sergi Joher, Enric Ballesteros, Emma Cebrian, Noemí Sánchez, Conxi Rodríguez-prieto
    Abstract:

    We present a quantitative physiognomic charac- terization of major macroalgal-dominated assemblages on coastal detritic bottoms of the continental shelf off Mal- lorca and Menorca (Balearic Islands, Western Mediterra- nean). In late spring of 2007 and 2008, 29 samples were collected by bottom trawling at depths between -52 and -93 m. These samples were then sorted and identified to their lowest taxonomic level. Statistical analyses distin- guished six different assemblage types: shallower water environments (-52 to -65 m in depth) were characterized by Osmundaria volubilis and Phyllophora crispa meadows and two types of Peyssonnelia beds; two assemblage types, Laminaria rodriguezii beds and ma e rl beds, were only present in deep-water environments (-77 to -81 m); and an assemblage dominated by P. crispa and Halopteris filicina was found in both shallow and deep waters (-57 to -93 m). We assess the distribution of these six assemblage types through the studied area.

  • Production of carbonate particles by phytobenthic communities on the Mallorca-Menorca shelf, northwestern Mediterranean Sea
    Deep Sea Research Part II: Topical Studies in Oceanography, 1997
    Co-Authors: Miquel Canals, Enric Ballesteros
    Abstract:

    Abstract In this paper the carbonate content and production, both at the species level and at the community level, is quantified in four areas of the Mallorca-Menorca shelf, northwestern Mediterranean Sea. Eight benthic communities are identified, each living at specific depth ranges and preferentially colonising either rocky or sedimented soft bottoms: (1) Photophilic algae, (2) Hemisciaphilic algae, (3) Coralligenous algal-dominated, (4) Coralligenous animal-dominated, (5) Caulerpa-Cymodocea meadows, (6) Posidonia oceanica meadows, (7) maerl and free-Peyssonelia beds, and (8) sandy bottom communities. Encrusting and maerl species of Corallinales and of the red algal genus Peyssonnelia and, to a lesser extent, the green alga Halimeda tuna, are the main carbonate producers. Most of the modern algal carbonate production in the Mallorca-Menorca shelf occurs at depths of less than 85–90 m, which is the lower limit of the coralligenous and maerl communities. Algal carbonate production in rocky areas is usually higher than that of soft bottoms, with the exception of the maerl beds in moderately deep waters (40–85 m). The highest algal carbonate production is found in coralligenous algal-dominated rocky bottoms (464.6 g m−2 year−1), photophilic algal communities (289.4 g m−2 year−1) and maerl beds (210 g m−2 year−1), while the lowest is displayed by seagrass meadows (60 to 70 g m−2 year−1) and sandy bottoms (0.5 g m−2 year−1). Nevertheless, the contribution of seagrass beds to benthic carbonate production in the Mallorca-Menorca shelf is outstanding due to the extent of the area occupied by these beds. The mean algal carbonate production rate over the upper 100 m water depth in the studied localities ranges from 90.60 to 123.89 g m−2 year−1, which correspond to the mostly sedimented Campos area and to the very rocky South Cabrera area, respectively. Overall mean carbonate production of the Mallorca-Menorca shelf is around 100 g CO3Ca m−2 year−1. These results may be viewed as a minimum estimate for total carbonate production on the Mallorca-Menorca shelf since they take into account only the phytobenthos.

Cassandra L. Quave - One of the best experts on this subject based on the ideXlab platform.

  • Peyssonnosides A–B, Unusual Diterpene Glycosides with a Sterically Encumbered Cyclopropane Motif: Structure Elucidation Using an Integrated Spectroscopic and Computational Workflow
    Journal of Organic Chemistry, 2019
    Co-Authors: Bhuwan K. Chhetri, Serge Lavoie, Anne Marie Sweeney-jones, Nazia Mojib, Vijay Raghavan, Kerstin Gagaring, Brandon Dale, Case W. Mcnamara, Katy M. Soapi, Cassandra L. Quave
    Abstract:

    Two sulfated diterpene glycosides featuring a highly substituted and sterically encumbered cyclopropane ring have been isolated from the marine red alga Peyssonnelia sp. Combination of a wide array of 2D NMR spectroscopic experiments, in a systematic structure elucidation workflow, revealed that peyssonnosides A–B (1–2) represent a new class of diterpene glycosides with a tetracyclo [7.5.0.01,10.05,9] tetradecane architecture. A salient feature of this workflow is the unique application of quantitative interproton distances obtained from the rotating frame Overhauser effect spectroscopy (ROESY) NMR experiment, wherein the β-d-glucose moiety of 1 was used as an internal probe to unequivocally determine the absolute configuration, which was also supported by optical rotatory dispersion (ORD). Peyssonnoside A (1) exhibited promising activity against liver stage Plasmodium berghei and moderate antimethicillin-resistant Staphylococcus aureus (MRSA) activity, with no cytotoxicity against human keratinocytes. Ad...

Ballesteros Enric - One of the best experts on this subject based on the ideXlab platform.

  • Contribution to the study of deep coastal detritic bottoms: the algal communities of the continental shelf off the Balearic Islands, Western Mediterranean
    'National Documentation Centre (EKT)', 2015
    Co-Authors: Joher S., Ballesteros Enric, Rodríguez-prieto C.
    Abstract:

    18 páginas, 5 figuras, 2 tablas.Three main algal-dominated coastal detritic communities from the continental shelf off Mallorca and Menorca (Balearic Islands, Western Mediterranean) are described herein: maërl beds dominated by Spongites fruticulosus and forests of Laminaria rodriguezii located in the Menorca channel, and Peyssonnelia inamoena beds found along the Southern coast of Menorca. There seems to be a gradient of disturbance from the highly disturbed Peyssonnelia beds to the almost undisturbed L. rodriguezii forests. Whether this gradient is the result of current and past anthropogenic pressure (e.g. trawling intensity) or is driven by natural environmental factors needs further assessment. Finally, the location of the target communities by means of ROV dives combined with the use of a Box-Corer dredge and beam trawl proved to be a good methodology in the study of the composition and structure of these deep water detritic communities.The CANAL0209 survey was financed by the MarViva Foundation, the Govern de les Illes Balears and the IEO. The MEDITS_ES05_09 survey was supported by the BADEMECO project, financed by the IEO and the European Union.Peer reviewe

  • Deep-water macroalgal-dominated coastal detritic assemblages on the continental shelf off Mallorca and Menorca (Balearic Islands, Western Mediterranean)
    'Walter de Gruyter GmbH', 2012
    Co-Authors: Joher S., Ballesteros Enric, Cebrian Emma, Sánchez N., Rodríguez-prieto C.
    Abstract:

    13 páginas, 2 figuras, 2 tablas.We present a quantitative physiognomic characterization of major macroalgal-dominated assemblages on coastal detritic bottoms of the continental shelf off Mallorca and Menorca (Balearic Islands, Western Mediterranean). In late spring of 2007 and 2008, 29 samples were collected by bottom trawling at depths between -52 and -93 m. These samples were then sorted and identified to their lowest taxonomic level. Statistical analyses distinguished six different assemblage types: shallower water environments (-52 to -65 m in depth) were characterized by Osmundaria volubilis and Phyllophora crispa meadows and two types of Peyssonnelia beds; two assemblage types, Laminaria rodriguezii beds and ma ë rl beds, were only present in deep-water environments (-77 to -81 m); and an assemblage dominated by P. crispa and Halopteris filicina was found in both shallow and deep waters (-57 to -93 m). We assess the distribution of these six assemblage types through the studied area.Sampling surveys were supported by the EVADEMED and INDEMARES projects financed by the IEO and the European Union. Emma Cebrian ’ s research was funded by the Juan de la Cierva program (MICINN-JDC).Peer reviewe

  • The deep-water Peyssonnelia beds from the Balearic islands (Western Mediterranean)
    'Wiley', 1994
    Co-Authors: Ballesteros Enric
    Abstract:

    Peyssonnelia bed distribution on continental shelf bottoms of the Balearic Islands (Western Mediterranean) ranges from 40 to 90 m depth. Different species of Peyssonnelia dominate these bottoms and, according to multivariate techniques, two main assemblages have been distinguished: the Peyssonnelia rosa-marina beds and the Peyssonnelia sp. beds, together with some transition samples between Peyssonnelia and maërl beds. Erect red algae are always abundant. Although average yearly irradiance reaching these beds is only 6.4-0.3% of subsurface irradiance, the species richness averages 45 species per sample (1600 cm2) and mean biomass is 2835 g dw. m-2. The high carbonate content of the living algae of these bottoms suggests that they are important contributors to the production of sediments in the Balearic continental shelf.Peer reviewe

  • Estructura de una comunidad de Halimeda tuna (Chlorophyceae, Caulerpales) en aguas profundas del Mediterráneo noroccidental
    'Editorial CSIC', 1991
    Co-Authors: Ballesteros Enric
    Abstract:

    A deep-water community dominated by Halimeda tuna and Mesophyllum lichenoides is described from the rocky bottoms of the North-Western Mediterranean. Other sciaphilic algae such as Udotea petiolata, some Peyssonnelia species and Lithophyllum expansum are also abundant. Algal biomass ranges between 1200 and 2100 g dw m-2 while percentage coverage ranges from 180 to 400%. The variations observed in algal coverage adequately describe the seasonal pattern of the community, which is characterized by a high development of erect algae in summer months and a low development in winter. The species richness, as well as both species and pattern diversity reach a maximum in summer. Summer's maximum irradiances and the low irradiances received between November and February seem to account for the seasonal pattern described above. Community structure and environmental factors affecting the deep-water Halimeda populations from the North Western Mediterranean are compared with those found in other deep-water seaweed communities from the Mediterranean and other seas. Finally, the phytosociological affinities between these Halimeda populations and the deep-water Mediterranean associations previously described is assessed.Se describe una comunidad dominada por Halimeda tuna y Mesophyllum lichenoides en los fondos rocosos profundos del Mediterráneo Noroccidental. Dichas especies coexisten con Udotea petiolata, diversas especies de Peyssonnelia y Lithophyllum expansum, como especies más aparentes. La biomasa algal oscila entre 1200 y 2100 g ps m-2 mientras que el porcentaje de recubrimiento varía entre el 180 y el 400 %. Las variaciones encontradas en el recubrimiento algal describen adecuadamente el comportamiento estacional de la comunidad, el cual se caracteriza por un elevado desarrollo del estrato erecto durante el verano. La riqueza específica y la diversidad son también elevadas en verano. La mayor disponibilidad de luz veraniega parece explicar este comportamiento. La estructura de la comunidad y los factores ambientales a los que está sometida se comparan con los descritos en otras comunidades profundas del Mediterráneo y otros mares. Finalmente, se discute la afinidad de estas poblaciones de Halimeda con las distintas asociaciones descritas en la zona circalitoral del Mediterráneo Occidental

  • Estructura de una comunidad de Halimeda tuna (Chlorophyceae, Caulerpales) en aguas profundas del Mediterráneo noroccidental
    'Editorial CSIC', 1991
    Co-Authors: Ballesteros Enric
    Abstract:

    17 páginas, 7 figuras, 6 tablas.[EN] A deep-water community dominated by Halimeda tuna and Mesophyllum lichenoides is described from the rocky bottoms of the North-Western Mediterranean. Other sciaphilic algae such as Udotea petiolata, some Peyssonnelia species and Lithophyllum expansum are also abundant. Algal biomass ranges between 1200 and 2100 g dw m-2 while percentage coverage ranges from 180 to 400%. The variations observed in algal coverage adequately describe the seasonal pattern of the community, which is characterized by a high development of erect algae in summer months and a low development in winter. The species richness, as well as both species and pattern diversity reach a maximum in summer. Summer's maximum irradiances and the low irradiances received between November and February seem to account for the seasonal pattern described above. Community structure and environmental factors affecting the deep-water Halimeda populations from the North Western Mediterranean are compared with those found in other deep-water seaweed communities from the Mediterranean and other seas. Finally, the phytosociological affinities between these Halimeda populations and the deep-water Mediterranean associations previously described is assessed.[ES] Se describe una comunidad dominada por Halimeda tuna y Mesophyllum lichenoides en los fondos rocosos profundos del Mediterráneo Noroccidental. Dichas especies coexisten con Udotea petiolata, diversas especies de Peyssonnelia y Lithophyllum expansum, como especies más aparentes. La biomasa algal oscila entre 1200 y 2100 g ps m-2 mientras que el porcentaje de recubrimiento varía entre el 180 y el 400 %. Las variaciones encontradas en el recubrimiento algal describen adecuadamente el comportamiento estacional de la comunidad, el cual se caracteriza por un elevado desarrollo del estrato erecto durante el verano. La riqueza específica y la diversidad son también elevadas en verano. La mayor disponibilidad de luz veraniega parece explicar este comportamiento. La estructura de la comunidad y los factores ambientales a los que está sometida se comparan con los descritos en otras comunidades profundas del Mediterráneo y otros mares. Finalmente, se discute la afinidad de estas poblaciones de Halimeda con las distintas asociaciones descritas en la zona circalitoral del Mediterráneo Occidental.Peer reviewe