21 results on '"Ivan Guala"'
Search Results
2. Detection of microplastics and phthalic acid esters in sea urchins from Sardinia (Western Mediterranean Sea)
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Clarissa Raguso, Daniele Grech, Alessandro Becchi, Paolo Giuseppe Ubaldi, Marina Lasagni, Ivan Guala, Francesco Saliu, Raguso, C, Grech, D, Becchi, A, Ubaldi, P, Lasagni, M, Guala, I, and Saliu, F
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Sea urchin ,Microplastics ,Phthalic Acids ,Esters ,Gonad ,Aquatic Science ,Plastic ,Oceanography ,Pollution ,Italy ,Tandem Mass Spectrometry ,Diethylhexyl Phthalate ,Sea Urchins ,Phthalate ,Mediterranean Sea ,Paracentrotus ,Animals ,Humans ,Plastics ,Chromatography, Liquid - Abstract
The occurrence of microplastics (MPs) and phthalic acid esters (PAEs) in wild purple sea urchins (Paracentrotus lividus) of Sardinia (Italy, Western Mediterranean Sea) was surveyed. Specifically, MPs were analyzed in the digestive tract by μFTIR and PAEs in the gonads by SPME-LC-MS/MS. 9 out of 22 specimens resulted contaminated with MPs and 20 displayed levels of PAEs over the quantification limit. A total of 23 MPs were detected with a maximum concentration of 4 microplastics/individual in the commercially undersized specimens. PAEs displayed average concentration of 32 ng/g, σ = 5.3 with maximum value of 77 ng/g. The most abundant congeners were DEHP (17 ng/g, σ = 4.3) and DBP (10 ng/g, σ = 2.5). Statistical analysis showed correlation between DEHP and fiber concentrations and among the concentration of MEP, DEP, DBP and BBzP. Due to local use of sea urchin gonads as gourmet delicacy, the potential human exposition to MPs and PAEs by consumption is also discussed.
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- 2022
3. Marine heatwaves drive recurrent mass mortalities in the Mediterranean Sea
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Joaquim Garrabou, Daniel Gómez‐Gras, Alba Medrano, Carlo Cerrano, Massimo Ponti, Robert Schlegel, Nathaniel Bensoussan, Eva Turicchia, Maria Sini, Vasilis Gerovasileiou, Nuria Teixido, Alice Mirasole, Laura Tamburello, Emma Cebrian, Gil Rilov, Jean‐Baptiste Ledoux, Jamila Ben Souissi, Faten Khamassi, Raouia Ghanem, Mouloud Benabdi, Samir Grimes, Oscar Ocaña, Hocein Bazairi, Bernat Hereu, Cristina Linares, Diego Kurt Kersting, Graciel la Rovira, Júlia Ortega, David Casals, Marta Pagès‐Escolà, Núria Margarit, Pol Capdevila, Jana Verdura, Alfonso Ramos, Andres Izquierdo, Carmen Barbera, Esther Rubio‐Portillo, Irene Anton, Paula López‐Sendino, David Díaz, Maite Vázquez‐Luis, Carlos Duarte, Nuria Marbà, Eneko Aspillaga, Free Espinosa, Daniele Grech, Ivan Guala, Ernesto Azzurro, Simone Farina, Maria Cristina Gambi, Giovanni Chimienti, Monica Montefalcone, Annalisa Azzola, Torcuato Pulido Mantas, Simonetta Fraschetti, Giulia Ceccherelli, Silvija Kipson, Tatjana Bakran‐Petricioli, Donat Petricioli, Carlos Jimenez, Stelios Katsanevakis, Inci Tuney Kizilkaya, Zafer Kizilkaya, Stephane Sartoretto, Rouanet Elodie, Sandrine Ruitton, Steeve Comeau, Jean‐Pierre Gattuso, Jean‐Georges Harmelin, Universidad de Alicante. Departamento de Ciencias del Mar y Biología Aplicada, Universidad de Alicante. Departamento de Fisiología, Genética y Microbiología, Biología Marina, Ecología Microbiana Molecular, Institut méditerranéen d'océanologie (MIO), Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'océanographie de Villefranche (LOV), Observatoire océanologique de Villefranche-sur-mer (OOVM), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS), ANR-17-MPGA-0001,4Oceans,Predicting future oceans under(2017), Agencia Estatal de Investigación (España), Ministerio de Ciencia, Innovación y Universidades (España), European Commission, Ministerio de Economía y Competitividad (España), Garrabou, Joaquim, Gómez-Gras, Daniel, Medrano, Alba, Cerrano, Carlo, Ponti, Massimo, Schlegel, Robert, Bensoussan, Nathaniel, Turicchia, Eva, Sini, Maria, Gerovasileiou, Vasili, Teixido, Nuria, Mirasole, Alice, Tamburello, Laura, Cebrian, Emma, Rilov, Gil, Ledoux, Jean-Baptiste, Souissi, Jamila Ben, Khamassi, Faten, Ghanem, Raouia, Benabdi, Mouloud, Grimes, Samir, Ocaña, Oscar, Bazairi, Hocein, Hereu, Bernat, Linares, Cristina, Kersting, Diego Kurt, la Rovira, Graciel, Ortega, Júlia, Casals, David, Pagès-Escolà, Marta, Margarit, Núria, Capdevila, Pol, Verdura, Jana, Ramos, Alfonso, Izquierdo, Andre, Barbera, Carmen, Rubio-Portillo, Esther, Anton, Irene, López-Sendino, Paula, Díaz, David, Vázquez-Luis, Maite, Duarte, Carlo, Marbà, Nuria, Aspillaga, Eneko, Espinosa, Free, Grech, Daniele, Guala, Ivan, Azzurro, Ernesto, Farina, Simone, Cristina Gambi, Maria, Chimienti, Giovanni, Montefalcone, Monica, Azzola, Annalisa, Mantas, Torcuato Pulido, Fraschetti, Simonetta, Ceccherelli, Giulia, Kipson, Silvija, Bakran-Petricioli, Tatjana, Petricioli, Donat, Jimenez, Carlo, Katsanevakis, Stelio, Kizilkaya, Inci Tuney, Kizilkaya, Zafer, Sartoretto, Stephane, Elodie, Rouanet, Ruitton, Sandrine, Comeau, Steeve, Gattuso, Jean-Pierre, Harmelin, Jean-Georges, Joaquim Garrabou, Daniel Gómez-Gra, Alba Medrano, Carlo Cerrano, Massimo Ponti, Robert Schlegel, Nathaniel Bensoussan, Eva Turicchia, Maria Sini, Vasilis Gerovasileiou, Nuria Teixido, Alice Mirasole, Laura Tamburello, Emma Cebrian, Gil Rilov, Jean-Baptiste Ledoux, Jamila Ben Souissi, Faten Khamassi, Raouia Ghanem, Mouloud Benabdi, Samir Grime, Oscar Ocaña, Hocein Bazairi, Bernat Hereu, Cristina Linare, Diego Kurt Kersting, Graciel la Rovira, Júlia Ortega, David Casal, Marta Pagès-Escolà, Núria Margarit, Pol Capdevila, Jana Verdura, Alfonso Ramo, Andres Izquierdo, Carmen Barbera, Esther Rubio-Portillo, Irene Anton, Paula López-Sendino, David Díaz, Maite Vázquez-Lui, Carlos Duarte, Nuria Marbà, Eneko Aspillaga, Free Espinosa, Daniele Grech, Ivan Guala, Ernesto Azzurro, Simone Farina, Maria Cristina Gambi, Giovanni Chimienti, Monica Montefalcone, Annalisa Azzola, Torcuato Pulido Manta, Simonetta Fraschetti, Giulia Ceccherelli, Silvija Kipson, Tatjana Bakran-Petricioli, Donat Petricioli, Carlos Jimenez, Stelios Katsanevaki, Inci Tuney Kizilkaya, Zafer Kizilkaya, Stephane Sartoretto, Rouanet Elodie, Sandrine Ruitton, Steeve Comeau, Jean-Pierre Gattuso, and Jean-Georges Harmelin
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Aquatic Organisms ,Foundation species ,Coralligenous habitats ,Marine conservation ,Climate Change ,[SDE.MCG]Environmental Sciences/Global Changes ,Impact assessment ,climate change ,coralligenous habitats ,foundation species ,habitat-forming species ,impact assessment ,marine conservation ,marine heatwaves ,temperate reefs ,Marine heatwaves ,Centro Oceanográfico de Baleares ,Coralligenous Assemblages ,climate change, coralligenous habitats, foundation species, habitat-forming species, impact assessment, marine conservation, marine heatwaves, temperate reefs ,Mediterranean Sea ,Responses ,Environmental Chemistry ,Climate change ,Temperate reefs ,Medio Marino ,[SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment ,Ecosystem ,[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography ,General Environmental Science ,[SDU.OCEAN]Sciences of the Universe [physics]/Ocean, Atmosphere ,Global and Planetary Change ,Climate-Change ,Ecology ,Surface Temperature ,[SDE.ES]Environmental Sciences/Environmental and Society ,Coastal ,Habitat-forming species - Abstract
Este artículo contiene 18 páginas, 4 figuras., Climate change is causing an increase in the frequency and intensity of marine heatwaves (MHWs) and mass mortality events (MMEs) of marine organisms are one of their main ecological impacts. Here, we show that during the 2015–2019 period, the Mediterranean Sea has experienced exceptional thermal conditions resulting in the onset of five consecutive years of widespread MMEs across the basin. These MMEs affected thousands of kilometers of coastline from the surface to 45 m, across a range of marine habitats and taxa (50 taxa across 8 phyla). Significant relationships were found between the incidence of MMEs and the heat exposure associated with MHWs observed both at the surface and across depths. Our findings reveal that the Mediterranean Sea is experiencing an acceleration of the ecological impacts of MHWs which poses an unprecedented threat to its ecosystems' health and functioning. Overall, we show that increasing the resolution of empirical observation is critical to enhancing our ability to more effectively understand and manage the consequences of climate change., This paper was supported by Euromarine. Joaquim Garrabou acknowledges the funding by the “Severo Ochoa Centre of Excellence” (CEX2019-000928-S), the MCIU/AEI/FEDER [HEATMED; RTI2018-095346-B-I00], Interreg-Med Programme MPA-Engage (1MED15_3.2_M2_337), the European Union Horizon 2020 research and innovation programme (Futuremares SEP-210597628). Nuria Teixido acknowledges the French National Research Agency (4Oceans-MOPGA grant, ANR-17-MPGA-0001) and internal funds from the Stazione Zoologica Anton Dohrn. Gil Rilov was supported by the Israel Ministry of Environmental Protection. Hocein Bazairi, Free Spinosa, and Vasilis Gerovasileiou acknowledge the funding by the MAVA Fondation (MedKeyHabitats I Project) and the European Commission (Ecap-MED II Project; projects implemented by UNEP/MAP-RAC/SPA). Alfonso Ramos was supported the CIESM “Tropical Signals,” Stelios Katsanevakis and Maria Sini were supported by the Project “Coastal Environment Observatory and Risk Management in Island Regions AEGIS+” (MIS 5047038), implemented within the Operational Programme “Competitiveness, Entrepreneurship and Innovation” (NSRF 2014–2020), co-financed by the Hellenic Government (Ministry of Development and Investments) and the European Union (European Regional Development Fund, Cohesion Fund), Stelios Katsanevakis, Maria Sini and Vasilis Gerovasileiou acknowledge the support of the MARISCA Project, co-funded by 85% by the EEA GRANTS, 2009–2014, and 15% by the Public Investments Programme (PIP) of the Hellenic Republic. Ivan Guala and Daniele Grech thanks thank the support of the project “Pinna nobilis—ricerca per la sopravvivenza: un'iniziativa di Citizen Science per tracciare la mortalità di massa di Pinna nobilis in Sardegna” project and the L/7 grant (CUP 87G17000070002) funded by the Regione Autonoma Sardegna. Jean-Baptiste Ledoux was funded by an assistant researcher contract framework of the RD Unit—UID/Multi/04423/2019—Interdisciplinary Centre of Marine and Environmental Research—financed by the European Regional Development Fund (ERDF) through COMPETE2020—Operational Program for Competitiveness and Internationalization (POCI) and national funds through FCT/MCTES (PIDDAC). This research was supported by the Strategic Funding UIDB/04423/2020 and UIDP/04423/2020 through national funds provided by the FCT—Foundation for Science and Technology and European Regional Development Fund (ERDF), in the framework of the program PT2020. Bernat Hereu and Cristina Linares acknowledge the support of the long-term monitoring programme of the catalan Natural Parks, funded by the Departament de Territori i Sostenibilitat of the Generalitat de Catalunya. Cristina Linares acknowledges the support of the ICREA Academia programme. David Díaz acknowledges the support the research grant CTM2016-77027-R of the Programa Estatal de Investigación, Desarrollo e Innovación Orientada a los Retos de la Sociedad and Program of Marines Strategies of Spain funded by MITERD. Jamila Ben Soussi was partially funded by the Fondation Albert 2 Monaco (MIMOSA Project) and the Tropical Signals Program of CIESM. Giovanni Chimienti was supported by the Italian Ministry of Education, University and Research (PON 2014–2020, AIM 1807508–1, Linea 1), by the Ente Parco Nazionale del Gargano (Research agreement with CoNISMa N. 21/2018), and by the National Geographic Society (Grant EC-176R-18). Nathaniel Bensoussan acknowledges financial support from the European Commission through the programme “Caroline Herschell” in the context of the action “Developing Downstream applications and services on BIO-PHYsical characterization of the seascape for COASTal management” (BIOPHYCOAST). Monica Montefalcone and Annalissa Azzola collected some of their data on MMEs in the frame of the project “Mare Caldo” funded by Greenpeace Italy. Núria Marbà acknowledges financial support from the Spanish Ministries of Economy and Competitiveness (CTM2012-32603, CGL2015-71809-P) and Ministerio de Ciencia, Innovación y Universidades (RTI2018-095441-B-C21). Diego K. Kersting acknowledges support by the postdoctoral fellowship programme Beatriu de Pinós funded by the Secretary of Universities and Research (Government of Catalonia) and the Horizon 2020 programme of research and innovation of the European Union under the Marie Sklodowska-Curie grant agreement No 801370.
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- 2022
4. Vibrio splendidus clade associated with a disease affecting Paracentrotus lividus (Lamarck, 1816) in Sardinia (Western Mediterranean)
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Daniele Grech, Daniela Mandas, Simone Farina, Ivan Guala, Roberto Brundu, Benedetto Cristo, Pier Augusto Panzalis, Fulvio Salati, and Francesca Carella
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Italy ,Mediterranean Sea ,Paracentrotus ,Animals ,Ecology, Evolution, Behavior and Systematics ,Vibrio - Abstract
This work reports for the first time the so-called bald sea urchin disease of the populations of Paracentrotus lividus in Sardinia (Italy). Following the disease occurrence reported by local fishermen of about 35% on the collected specimens for commercial purpose, the phenomenon was evaluated in two areas. Animals displayed external lesions represented by loss of spines and greenish/brownish skeleton patches. Microscopy of exoskeleton and tube feet showed haemocytosis with associated bacteria; gut and intestine histopathology revealed inflammatory lesions of different type and intensity. Microbiological and molecular analysis revealed the presence of the strains belonging to the Vibrio splendidus clade. Due to the important ecological role of Paracentrotus lividus in the Mediterranean Sea, this report represents a wake-up call for the entire basin worth of further insights.
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- 2022
5. Sea urchin harvest inside marine protected areas: an opportunity to investigate the effects of exploitation where trophic upgrading is achieved
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Giulia Ceccherelli, Piero Addis, Fabrizio Atzori, Nicoletta Cadoni, Marco Casu, Stefania Coppa, Mario De Luca, Giuseppe Andrea de Lucia, Simone Farina, Nicola Fois, Francesca Frau, Vittorio Gazale, Daniele Grech, Ivan Guala, Mariano Mariani, Massimo SG Marras, Augusto Navone, Arianna Pansini, Pieraugusto Panzalis, Federico Pinna, Alberto Ruiu, Fabio Scarpa, and Luigi Piazzi
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General Neuroscience ,General Medicine ,General Agricultural and Biological Sciences ,General Biochemistry, Genetics and Molecular Biology - Abstract
Background Marine protected areas (MPAs) usually have both positive effects of protection for the fisheries’ target species and indirect negative effects for sea urchins. Moreover, often in MPAs sea urchin human harvest is restricted, but allowed. This study is aimed at estimating the effect of human harvest of the sea urchin Paracentrotus lividus within MPAs, where fish exploitation is restricted and its density is already controlled by a higher natural predation risk. The prediction we formulated was that the lowest densities of commercial sea urchins would be found where human harvest is allowed and where the harvest is restricted, compared to where the harvest is forbidden. Methods At this aim, a collaborative database gained across five MPAs in Sardinia (Western Mediterranean, Italy) and areas outside was gathered collecting sea urchin abundance and size data in a total of 106 sites at different degrees of sea urchin exploitation: no, restricted and unrestricted harvest sites (NH, RH and UH, respectively). Furthermore, as estimates made in past monitoring efforts (since 2005) were available for 75 of the sampled sites, for each of the different levels of exploitation, the rate of variation in the total sea urchin density was also estimated. Results Results have highlighted that the lowest sea urchin total and commercial density was found in RH sites, likely for the cumulative effects of human harvest and natural predation. The overall rate of change in sea urchin density over time indicates that only NH conditions promoted the increase of sea urchin abundance and that current local management of the MPAs has driven towards an important regression of populations, by allowing the harvest. Overall, results suggest that complex mechanisms, including synergistic effects between natural biotic interactions and human pressures, may occur on sea urchin populations and the assessment of MPA effects on P. lividus populations would be crucial to guide management decisions on regulating harvest permits. Overall, the need to ban sea urchin harvest in the MPAs to avoid extreme reductions is encouraged, as inside the MPAs sea urchin populations are likely under natural predation pressures for the trophic upgrading.
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- 2022
6. The challenge of managing the commercial harvesting of the sea urchin
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Simone, Farina, Maura, Baroli, Roberto, Brundu, Alessandro, Conforti, Andrea, Cucco, Giovanni, De Falco, Ivan, Guala, Stefano, Guerzoni, Giorgio, Massaro, Giovanni, Quattrocchi, Giovanni, Romagnoni, and Walter, Brambilla
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Conservation Biology ,Ecology ,Population Biology ,Marine protected area ,Marine Biology ,Sustainable harvesting ,Population dynamic ,Spatial management ,Marine coastal ecosystems ,Stock sustainability ,Paracentrotus lividus ,Aquaculture, Fisheries and Fish Science ,Local fisheries management ,Environmental constrains ,Sea urchins - Abstract
Sea urchins act as a keystone herbivore in marine coastal ecosystems, regulating macrophyte density, which offers refuge for multiple species. In the Mediterranean Sea, both the sea urchin Paracentrotus lividus and fish preying on it are highly valuable target species for artisanal fisheries. As a consequence of the interactions between fish, sea urchins and macrophyte, fishing leads to trophic disorders with detrimental consequences for biodiversity and fisheries. In Sardinia (Western Mediterranean Sea), regulations for sea urchin harvesting have been in place since the mid 90s. However, given the important ecological role of P. lividus, the single-species fishery management may fail to take into account important ecosystem interactions. Hence, a deeper understanding of population dynamics, their dependance on environmental constraints and multispecies interactions may help to achieve long-term sustainable use of this resource. This work aims to highlight how sea urchin population structure varies spatially in relation to local environmental constraints and species interactions, with implications for their management. The study area (Sinis Peninsula, West Sardinia, Italy) that includes a Marine Reserve was divided into five sectors. These display combinations of the environmental constraints influencing sea urchin population dynamics, namely type of habitat (calcareous rock, granite, basalt, patchy and continuous meadows of Posidonia oceanica), average bottom current speed and predatory fish abundance. Size-frequency distribution of sea urchins under commercial size (
- Published
- 2020
7. Performance of a baited underwater video system vs. the underwater visual census technique in assessing the structure of fish assemblages in a Mediterranean marine protected area
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Alberto Ruiu, Francesco Perretti, Michele Manghi, Fabio Ronchetti, Giulia Ceccherelli, Gabriella La Manna, Daniele Grech, and Ivan Guala
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fish fauna monitoring ,Environmental Engineering ,Sparidae ,biology ,Range (biology) ,Fauna ,BRUV ,Aquatic Science ,Oceanography ,biology.organism_classification ,Chromis chromis ,Fishery ,Geography ,Habitat ,video-based system ,Abundance (ecology) ,Marine protected area ,Mediterranean Sea ,Species richness ,Ecology, Evolution, Behavior and Systematics - Abstract
Accurate, rapid and cost-effective fish assemblage monitoring is fundamental for marine protected area (MPA) management as a pivotal tool to verify whether and to what extent MPA conservation objectives have been achieved and to redefine these objectives in the framework of an adaptive management. Recently, there has been a sharp increase in the number of video-based methods to study fish fauna, such as baited remote underwater video (BRUV) systems, that, depending on the objectives of the monitoring, can provide complementary or additional data to the more commonly used underwater visual census (UVC). Even though BRUV systems have been widely used in a wide range of geographic contexts and habitats, their use in the Mediterranean basin is still sporadic and the evaluation of the efficiency of BRUV systems and whether they can be used to complement other techniques needs investigation. Thus, the objective of this study was to assess the performance of a BRUV system in a Mediterranean MPA and to evaluate its effectiveness in assessing the structure of fish assemblages (abundance and species richness) by comparing estimates with those obtained by the UVC technique. The fish fauna were monitored by BRUV and UVC in the Capo Caccia – Isola Piana Marine Protected Area (Sardinia, Italy), in July and October-November 2020, at four sampling sites and two areas, hundreds of meters apart, for each site. Overall, 46 taxa and a total of 3620 individuals were observed by BRUV, while 36 taxa and a total of 2995 individuals were observed by UVC. The species first observed in front of the camera’s field of view and able to reach the maximum abundance were the planktivores (Chromis chromis and Oblada melanura) followed by several carnivorous species belonging to the families Labridae, Serranidae and Sparidae, and lastly two carnivores (Mullus surmuletus and Mugilidae spp.) and some high-level predators (Dentex dentex, Seriola dumerili, Sphyraena viridensis, Dicentrarchus labrax). The maximum species richness and abundance were reached between 39 and 50 min. The cumulative species richness increased until around 30 min. Species richness was higher during the BRUV compared to the UVC monitoring. The consistency in findings between BRUV and UVC and a better performance of BRUV in detecting some species (mainly high-level predators), supports BRUV as an additional technique for describing and quantifying species richness and abundance also in the Mediterranean Sea. Based on the results of this study, the advantages/disadvantages, shortcomings, suggestions and resources needed for the two techniques are outlined.
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- 2021
8. Variations in coralligenous assemblages from local to biogeographic spatial scale
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G. La Manna, M.F. Cinti, Giulia Ceccherelli, Daniele Grech, Ivan Guala, Arianna Pansini, Patrizia Stipcich, Federico Pinna, and Luigi Piazzi
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0106 biological sciences ,Biogeography ,Aquatic Science ,Oceanography ,010603 evolutionary biology ,01 natural sciences ,Hierarchical sampling ,Mediterranean sea ,Animals ,Reef ,Ecosystem ,geography ,geography.geographical_feature_category ,Coral Reefs ,Ecology ,010604 marine biology & hydrobiology ,Biodiversity ,General Medicine ,Anthozoa ,Seaweed ,Pollution ,Italy ,Habitat ,Spatial ecology ,Spatial variability ,Scale (map) - Abstract
The present study aims at contributing to the knowledge of the spatial variability of coralligenous reefs through the evaluation of patterns ranging from local to biogeographic scale around the island of Sardinia. The coralligenous reef assemblages of six areas were studied through a hierarchical sampling design: three sites per area were selected, in each site three plots were sampled and in each plot ten photographic samples were collected. The structure of coralligenous reefs across closed biogeographic regions is described, highlighting that nearly pristine assemblages, although characterized by similar high diversity, can be either dominated by animals, such as gorgonians and bryozoans, or macroalgae. The observed variations seem largely related to biogeographic patterns rather than spatial distance, supporting the need to identify specific reference conditions to assess the ecological quality of this habitat depending on the biogeographic area to be monitored.
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- 2021
9. Decreased pH impairs sea urchin resistance to predatory fish: A combined laboratory-field study to understand the fate of top-down processes in future oceans
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Gianni Brundu, F. Leggieri, Ivan Guala, Anuta Chindris, Valentina Asnaghi, Mariachiara Chiantore, M. Scolamacchia, Simone Farina, and Barbara Loi
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0106 biological sciences ,Oceans and Seas ,Cascading effects ,Aquatic Science ,Test (biology) ,Coastal zone ,Oceanography ,010603 evolutionary biology ,01 natural sciences ,Paracentrotus lividus ,Predatory fish ,biology.animal ,Animals ,Seawater ,Ecosystem ,Benthic ecology ,Ocean acidification ,Overexploitation ,Fishes ,Hydrogen-Ion Concentration ,Sea Urchins ,Sea urchin ,biology ,Ecology ,010604 marine biology & hydrobiology ,General Medicine ,biology.organism_classification ,Pollution ,Benthic zone ,Environmental science - Abstract
Changing oceans represent a serious threat for a wide range of marine organisms, with severe cascading effects on ecosystems and their services. Sea urchins are particularly sensitive to decreased pH expected for the end of the century and their key ecological role in regulating community structure and functioning could be seriously compromised. An integrated approach of laboratory and field experiments has been implemented to investigate the effects of decreased pH on predator-prey interaction involving sea urchins and their predators. Our results suggest that under future Ocean Acidification scenarios adult sea urchins defence strategies, such as spine length, test robustness and oral plate thickness, could be compromised together with their survival chance to natural predators. Sea urchins represent the critical linkage between top-down and bottom-up processes along Mediterranean rocky reefs, and the cumulative impacts of global and local stressors could lead to a decline producing cascading effects on benthic ecosystems.
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- 2020
10. Influence of seasonal and environmental patterns on the lipid content and fatty acid profiles in gonads of the edible sea urchin Paracentrotus lividus from Sardinia
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Maria Filippa Addis, Ivan Guala, Tonina Roggio, Maura Baroli, Sergio Uzzau, Riccardo Melis, Silvia Siliani, Roberto Anedda, Roberta Sanna, and Barbara Loi
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0106 biological sciences ,endocrine system ,Zoology ,Aquatic Science ,Oceanography ,01 natural sciences ,Paracentrotus lividus ,Cyclical trend ,biology.animal ,Mediterranean Sea ,Animals ,Gonads ,Sea urchin ,Ecosystem ,chemistry.chemical_classification ,photoperiodism ,biology ,Ecology ,010604 marine biology & hydrobiology ,Fatty Acids ,Sampling (statistics) ,Fatty acid ,04 agricultural and veterinary sciences ,General Medicine ,Lipid Metabolism ,biology.organism_classification ,Lipids ,Pollution ,Sea surface temperature ,Italy ,chemistry ,Lipid content ,Paracentrotus ,040102 fisheries ,0401 agriculture, forestry, and fisheries ,Seasons - Abstract
The influence of seasonal and environmental patterns on the lipid fraction of Paracentrotus lividus gonads was investigated. For this purpose, sea urchins were collected monthly over a year from two Sardinian coastal areas. Total lipids in gonads follow an annual cyclical trend, described by a sine wave curve, that it is more influenced by season than by growing area. The lowest lipid content in gonads corresponds to a high percentage of mature reproductive stages (i.e. winter season), independently of sampling area. A variation in total lipid content follows a change in photoperiod, while it is related to sea surface temperature. Multivariate analysis on fatty acid profiles of gonads, detected by gas chromatography, clusters the collected specimens mainly according to the sampling area, secondly according to the sites within the same sampling area and finally according to season.
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- 2016
11. The challenge of managing the commercial harvesting of the sea urchin Paracentrotus lividus: advanced approaches are required
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Giovanni De Falco, Giovanni Quattrocchi, Giovanni Romagnoni, Stefano Guerzoni, Andrea Cucco, Giorgio Massaro, Walter Brambilla, Ivan Guala, Maura Baroli, Simone Farina, A. Conforti, and Roberto Brundu
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0106 biological sciences ,Population ,lcsh:Medicine ,Population dynamic ,010603 evolutionary biology ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,Paracentrotus lividus ,Predatory fish ,Mediterranean sea ,biology.animal ,14. Life underwater ,education ,Sea urchins ,Sea urchin ,education.field_of_study ,biology ,Ecology ,010604 marine biology & hydrobiology ,General Neuroscience ,lcsh:R ,Marine reserve ,Sustainable harvesting ,General Medicine ,biology.organism_classification ,Spatial management ,Posidonia oceanica ,Environmental science ,Marine protected area ,Local fisheries management ,General Agricultural and Biological Sciences - Abstract
Sea urchins act as a keystone herbivore in marine coastal ecosystems, regulating macrophyte density, which offers refuge for multiple species. In the Mediterranean Sea, both the sea urchin Paracentrotus lividus and fish preying on it are highly valuable target species for artisanal fisheries. As a consequence of the interactions between fish, sea urchins and macrophyte, fishing leads to trophic disorders with detrimental consequences for biodiversity and fisheries. In Sardinia (Western Mediterranean Sea), regulations for sea urchin harvesting have been in place since the mid 90s. However, given the important ecological role of P. lividus, the single-species fishery management may fail to take into account important ecosystem interactions. Hence, a deeper understanding of population dynamics, their dependance on environmental constraints and multispecies interactions may help to achieve long-term sustainable use of this resource. This work aims to highlight how sea urchin population structure varies spatially in relation to local environmental constraints and species interactions, with implications for their management. The study area (Sinis Peninsula, West Sardinia, Italy) that includes a Marine Reserve was divided into five sectors. These display combinations of the environmental constraints influencing sea urchin population dynamics, namely type of habitat (calcareous rock, granite, basalt, patchy and continuous meadows of Posidonia oceanica), average bottom current speed and predatory fish abundance. Size-frequency distribution of sea urchins under commercial size (P. oceanica meadows. The density of middle-sized sea urchins was more abundant in calcareous rock than in basalt, granite or P. oceanica. High densities of recruits resulted significantly correlated to low values of average bottom current speed, while a negative trend between the abundance of middle-sized sea urchins and predatory fish was found. Our results point out the need to account for the environmental constraints influencing local sea urchin density in fisheries management.
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- 2020
12. Hydrodynamic patterns favouring sea urchin recruitment in coastal areas: A Mediterranean study case
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Andrea Cucco, Ivan Guala, Simone Farina, and Giovanni Quattrocchi
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0106 biological sciences ,Mediterranean climate ,Water mass ,Aquatic Science ,Oceanography ,Spatial distribution ,010603 evolutionary biology ,01 natural sciences ,Paracentrotus lividus ,biology.animal ,Mediterranean Sea ,Animals ,Ecosystem ,Sea urchin ,Invertebrate ,Demography ,biology ,Ecology ,010604 marine biology & hydrobiology ,General Medicine ,biology.organism_classification ,Pollution ,Italy ,Benthic zone ,Hydrodynamics ,Paracentrotus ,Environmental science ,Environmental Monitoring - Abstract
In invertebrate fisheries, sea urchin harvesting continues to grow with dramatic consequences for benthic ecosystems. The identification of areas with a marked natural recruitment and the mechanisms regulating it is crucial for the conservation of benthic communities and for planning the sustainable harvesting. This study evaluates the spatial distribution and density of recruits of the edible sea urchin Paracentrotus lividus along the Sinis + Peninsula (Sardinia) and explores its significant relationships with the local oceanographic features. Our results reveal that recruitment is favoured in areas with slow currents and high levels of confinement and trapping of the water masses. Analysis of the residual circulation indicates that the presence of local standing circulation structures promotes the sea urchin recruitment process. Our findings emphasize the importance of managing local sea urchin harvesting as a system of populations with their demographic influence mainly dependent on the most important ecological driver that is the recruitment.
- Published
- 2017
13. Determinants of Paracentrotus lividus sea urchin recruitment under oligotrophic conditions: Implications for conservation management
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Silvia Oliva, Francesco Mura, Simone Farina, Pierre Antoine Ariotti, Stefania Pinna, Davide Agnetta, Ivan Guala, and Giulia Ceccherelli
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0106 biological sciences ,Conservation of Natural Resources ,food.ingredient ,Food Chain ,Aquatic Science ,Oceanography ,010603 evolutionary biology ,01 natural sciences ,Paracentrotus lividus ,Predatory fish ,food ,biology.animal ,Paracentrotus ,Animals ,Sea urchin ,Ecosystem ,biology ,Ecology ,010604 marine biology & hydrobiology ,Coralline algae ,General Medicine ,biology.organism_classification ,Pollution ,Fishery ,Habitat ,Benthic zone ,Quadrat - Abstract
Sea urchins may deeply shape the structure of macrophyte-dominated communities and require the implementation of sustainable management strategies. In the Mediterranean, the identification of the major recruitment determinants of the keystone sea urchin species Paracentrotus lividus is required, so that source areas of the populations can be identified and exploitation or programmed harvesting can be spatially managed. In this study a collection of eight possible determinants, these encompassing both the biotic (larvae, adult sea urchins, fish, encrusting coralline algae, habitat type and spatial arrangement of habitats) and abiotic (substrate complexity and nutritional status) realms was considered at different spatial scales (site, area, transect and quadrat). Data from a survey including sites subject to different levels of human influence (i.e. from urbanized to protected areas), but all corresponding to an oligotrophic and low-populated region were fitted by means of a generalized linear mixed model. Despite the extensive sampling effort of benthic quadrats, an overall paucity of recruits was found, recruits being aggregated in a very small number of quadrats and in few areas. The analysis of data detected substrate complexity, and adult sea urchin and predatory fish abundances as the momentous determinants of Paracentrotus lividus recruitment. Possible mechanisms of influence are discussed beyond the implications of conservation management.
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- 2015
14. Effects of no-take area size and age of marine protected areas on fisheries yields: a meta-analytical approach
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P. Martín-Sosa, Vanessa Stelzenmüller, Romain Crec'hriou, Carlo Pipitone, Iacopo Bertocci, Raquel Goñi, Francesc Maynou, Giovanni D’Anna, Ivan Guala, Ben Stobart, Concepción Marcos, Julio Sánchez-Meca, Carmelo Dorta, Patrick J. Schembri, Angel Pérez-Ruzafa, Ricardo S. Santos, Ruth Higgins, Frederic Vandeperre, Mark Dimech, Oscar Esparza, C. Ojeda-Martínez, Aitor Forcada, Pedro Afonso, Laurence Le Direach, and J.M. Falcón
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Fishery ,Biodiversity conservation ,Time frame ,Geography ,Marine reserve ,Marine protected area ,Fisheries management ,Management, Monitoring, Policy and Law ,Aquatic Science ,Catch per unit effort ,Oceanography ,Ecology, Evolution, Behavior and Systematics - Abstract
Marine protected areas (MPAs) are often promoted as tools for biodiversity conservation as well as for fisheries management. Despite increasing evidence of their usefulness, questions remain regarding the optimal design of MPAs, in particular concerning their function as fisheries management tools, for which empirical studies are still lacking. Using 28 data sets from seven MPAs in Southern Europe, we developed a meta-analytical approach to investigate the effects of protection on adjacent fisheries and asking how these effects are influenced by MPA size and age. Southern European MPAs showed clear effects on the surrounding fisheries, on the ‘catch per unit effort’ (CPUE) of target species, but especially on the CPUE of the marketable catch. These effects depended on the time of protection and on the size of the no-take area. CPUE of both target species and the marketable catch increased gradually by 2‐4% per year over a long time period (at least 30 years). The influence of the size of the no-take area appeared to be more complex. The catch rates of the entire fishery in and around the MPA were higher when the no-take areas were smaller. Conversely, catch rates of selected fisheries that were expected to benefit most from protection increased when the no-take area was larger. Our results emphasize the importance of MPA size on its export functions and suggest that an adequate, often extended, time frame be used for the management and the evaluation of effectiveness of MPAs.
- Published
- 2010
15. Density and distribution patterns of the endangered species Pinna nobilis within a Posidonia oceanica meadow in the Gulf of Oristano (Italy)
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Giorgio Massaro, G.A. De Lucia, Stefania Coppa, Ivan Guala, and Monica Bressan
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education.field_of_study ,biology ,Ecology ,Population ,Endangered species ,Aquatic Science ,Population ecology ,biology.organism_classification ,Geography ,Mediterranean sea ,Habitat ,Posidonia oceanica ,Marine protected area ,education ,Pinna nobilis - Abstract
Pinna nobilis is an endemic bivalve of the Mediterranean Sea. In the last decades P. nobilis populations have declined drastically due to increasing anthropogenic pressure and it has been declared a protected species since 1992. Despite the need for conservation, knowledge of the ecology and monitoring of the main populations of P. nobilis are limited. This study considered a population living within a Posidonia oceanica meadow in the Gulf of Oristano (western Mediterranean, Italy). The study area, about 150 hectares, part of which is included within a Marine Protected Area and a Site of Community Importance, was subdivided in 3 sub-areas. The percentage cover of different habitat types (P. oceanica, dead matte and sand) in each sub-area was measured and meadow features (substrate coverage, matte compactness and shoot density) characterized. The hypotheses of differences in density, percentage of dead individuals, population structure, shell burial level and orientation of P. nobilis, were investigated according to sub-areas and to habitat type. The spatial distribution was patchy, and the habitat type resulted a key factor in determining both density and distribution. A strong edge effect was demonstrated: more than half of the observed individuals colonized the P. oceanica border. Matte compactness and shoot density were found to affect the density and distribution of P. nobilis. Shell burial level and percentage of dead individuals varied with sub-areas and habitat types. Size distribution was bimodal and common shell orientation was observed in two sub-areas. These results contribute to increase the knowledge of population ecology of this species and to provide useful information for implementing conservation policies.
- Published
- 2010
16. Landscape configuration of seagrass meadows regulates sea urchins predation in a Marine Protected Area: what is the role of bottom predators?
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Matteo Spanu, Luigi Piazzi, Silvia Oliva, Ivan Guala, Rodrigo Pires da Silva, Simone Farina, and Giulia Ceccherelli
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education.field_of_study ,biology ,Ecology ,Population ,biology.organism_classification ,Paracentrotus lividus ,Predation ,Fishery ,Seagrass ,Habitat ,Posidonia oceanica ,Guild ,Environmental science ,Marine protected area ,education - Abstract
In Mediterranean benthic ecosystems of shallow water local-scale predation maintains a main control on both sea urchin population and the ecological structure of macrophyte community. The use of the habitat by local predator guild in dependence on the regional context shapes prey distributions across the environment. On rocky habitat, the sea urchin Paracentrotus lividus is widely known as prey of apex fish predators that indirectly shape the structure of benthic assemblages whereas, in structured Posidonia oceanica, P. lividus can find shelter from predators. In this study, we assessed survival rates of P. lividus in a Marine Protected Area (Sardinia) at the aim to evaluate the role of composition and configuration of landscape on its predation risk. Sites of different landscapes were selected in function of their heterogeneity estimated according to the different proportions and spatial interspersion of four classes of habitats defined on the basis of P. oceanica meadows arrangement: (1) continuous, (2) fragmented and (3) patchy meadows and (4) absence of seagrass (i.e. rocky bottom with macroalgae communities). In order to capture the domain of the ecological process a sampling grain 5x5 meters was used as minimal spatial resolution at which information is assessed. Specifically continuous sampling units in a grid of 7x7 cells yield landscape quadrats of 35 × 35 m and allowed a finer description of the spatial pattern. For each cell we also estimated structural variables of seagrass habitats such as unburied mat, shoot density, canopy height, cover percent, roughness and the natural abundances of prey and predators. After placing the tagged sea urchins, we daily observed the survival rates for twenty days. Predation risk was significantly higher in continuous and fragmented seagrass habitats and predator marks were typically produced by gastropod’s attacks. Landscape indices are used to correlate the amount of available habitat for gastropods movements with sea urchin’s predation risk. Interestingly, estimated predation rate also was negatively correlated with natural sea urchins density across grid cells. Results suggest that, although fishes are considered among the most important pressures on sea urchin population, especially in effective MPAs, bottom predators’ control can be relevant in structurally complex environment such as seagrasses.
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- 2015
17. Monitoring of Posidonia oceanica meadows in the Telašćica Nature Park (Croatia)
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Zrinka Jakl, Milena Šijan, Mosor Prvan, Maya Sertic, Vanja Čavrak, Lorena Derezanin, Stefano Boi, and Ivan Guala
- Abstract
Monitoring of marine priority habitats has been recently undertaken in the Telašćica Nature Park (Croatia) in compliance with the management plan developed within the MedPAN South project. Assessment of the state of Posidonia oceanica meadows was made in 2011, 2012 and 2014, in five locations subjected to different anthropogenic pressure. The monitoring was mainly aimed to establish the presence of disturbance in locations that are highly frequented by recreational boaters. Using an empirical assessment of frequent boat use, meadows were defined as “anchoring” (four locations - Čuška Dumboka, Kobiljak, Lučica, Sestrica – that are potentially subjected to high pressure from boating activities) or “no-anchoring” (one location - Garmenjak - where boating activites are considered negligible since the area is not a preferred destination for boater). Structural descriptors of the meadows (i.e shoot density and the Conservation Index) were assessed at different sites at each location, by means of direct surveys in SCUBA diving. Results indicate clear signs of deterioration at the locations that are subjected to high pressure of anchoring. Overall, shoot density at the "no-anchoring" sites had significant higher values than the "anchoring" sites, by around 31% to 45% higher, over the three years of investigations. Changes in values of the Conservation Index were smaller; 10% to 15% higher in “no-anchoring” than "anchoring" sites. Among the “anchoring” locations, Čuška Dumboka and Kobiljak showed the lowest values of shoot density and Conservation Index (as a consequence of the highest cover of dead matte), over the three years of monitoring. The combined use of the two descriptors seems to be effective in obtaining information on the condition of the seagrass meadows and strengthens the a priori assumption that mechanical disturbance of anchors affects P. oceanica adversely by enhancing regression of the meadows. The management authority is now implementing a series of actions to reduce human pressures and promote a more sustainable approach to nautical tourism. Monitoring of boating frequency and activities (number and size of boats, anchor type), is recommended to assess the effective pressure of anchoring and understand whether the different conditions of meadows under pressure correspond to the different levels of disturbance or if other factors along with anchoring are influencing the seagrass beds.
- Published
- 2015
18. Hard time to be parents? Sea urchin fishery shifts potential reproductive contribution of population onto the shoulders of the young adults
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Rodrigo Pires da Silva, Simone Farina, Maura Baroli, Ivan Guala, Barbara Loi, and Gianni Brundu
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0106 biological sciences ,Mediterranean climate ,Sea urchin ,Conservation Biology ,Population ,lcsh:Medicine ,Marine Biology ,Population structure ,010603 evolutionary biology ,01 natural sciences ,General Biochemistry, Genetics and Molecular Biology ,Paracentrotus lividus ,Mediterranean sea ,biology.animal ,Gonads ,education ,education.field_of_study ,Ecology ,biology ,Gamete output ,010604 marine biology & hydrobiology ,General Neuroscience ,lcsh:R ,General Medicine ,biology.organism_classification ,Fishery ,Gonadosomatic Index ,Gonadosomatic index ,Fishing ,Marine protected area ,General Agricultural and Biological Sciences ,Bay ,Reproductive potential - Abstract
BackgroundIn Sardinia, as in other regions of the Mediterranean Sea, sustainable fisheries of the sea urchinParacentrotus lividushave become a necessity. At harvesting sites, the systematic removal of large individuals (diameter ≥ 50 mm) seriously compromises the biological and ecological functions of sea urchin populations. Specifically, in this study, we compared the reproductive potential of the populations from Mediterranean coastal areas which have different levels of sea urchin fishing pressure. The areas were located at Su Pallosu Bay, where pressure is high and Tavolara-Punta Coda Cavallo, a marine protected area where sea urchin harvesting is low.MethodsReproductive potential was estimated by calculating the gonadosomatic index (GSI) from June 2013 to May 2014 both for individuals of commercial size (diameter without spines, TD ≥ 50 mm) and the undersized ones with gonads (30 ≤ TD < 40 mm and 40 ≤ TD < 50 mm). Gamete output was calculated for the commercial-size class and the undersized individuals with fertile gonads (40 ≤ TD < 50 mm) in relation to their natural density (gamete output per m2).ResultsThe reproductive potential of populations was slightly different at the beginning of the sampling period but it progressed at different rates with an early spring spawning event in the high-pressure zone and two gamete depositions in early and late spring in the low-pressure zone. For each fertile size class, GSI values changed significantly during the year of our study and between the two zones. Although the multiple spawning events determined a two-fold higher total gamete output of population (popTGO) in the low-pressure zone, the population mean gamete output (popMGO) was similar in the two zones. In the high-pressure zone, the commercial-sized individuals represented approximatively 5% of the population, with almost all the individuals smaller than 60 mm producing an amount of gametes nearly three times lower than the undersized ones. Conversely, the high density of the undersized individuals released a similar amount of gametes to the commercial-size class in the low-pressure zone.DiscussionOverall, the lack of the commercial-size class in the high-pressure zone does not seem to be very alarming for the self-supporting capacity of the population, and the reproductive potential contribution seems to depend more on the total density of fertile sea urchins than on their size. However, since population survival in the high-pressure zone is supported by the high density of undersized sea urchins between 30 and 50 mm, management measures should be addressed to maintain these sizes and to shed light on the source of the larval supply.
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- 2017
19. The Seagrass Effect Turned Upside Down Changes the Prospective of Sea Urchin Survival and Landscape Implications
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Giulia Ceccherelli, Rodrigo Pires da Silva, Simone Farina, Luigi Piazzi, Ivan Guala, and Silvia Oliva
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0106 biological sciences ,Population Dynamics ,lcsh:Medicine ,Predation ,Marine and Aquatic Sciences ,01 natural sciences ,Predator-Prey Dynamics ,Mediterranean sea ,Oceans ,Marine Fish ,lcsh:Science ,Alismatales ,Multidisciplinary ,Ecology ,biology ,Marine reserve ,Fishes ,Animal Models ,Trophic Interactions ,Habitats ,Seagrass ,Community Ecology ,Habitat ,Benthic zone ,Posidonia oceanica ,Vertebrates ,Paracentrotus ,Research Article ,Echinoderms ,Food Chain ,Marine Biology ,Research and Analysis Methods ,010603 evolutionary biology ,Ecosystems ,Paracentrotus lividus ,Model Organisms ,Bodies of water ,Mediterranean Sea ,Animals ,Ecosystem ,Population Biology ,010604 marine biology & hydrobiology ,lcsh:R ,Ecology and Environmental Sciences ,Organisms ,Biology and Life Sciences ,biology.organism_classification ,Invertebrates ,Fishery ,Species Interactions ,Predatory Behavior ,Sea Urchins ,Earth Sciences ,lcsh:Q ,BIO/07 Ecologia - Abstract
Habitat structure plays an important mediating role in predator-prey interactions. However the effects are strongly dependent on regional predator pools, which can drive predation risk in habitats with very similar structure in opposite directions. In the Mediterranean Sea predation on juvenile sea urchins is commonly known to be regulated by seagrass structure. In this study we test whether the possibility for juvenile Paracentrotus lividus to be predated changes in relation to the fragmentation of the seagrass Posidonia oceanica (four habitat classes: continuous, low-fragmentation, high-fragmentation and rocks), and to the spatial arrangement of such habitat classes at a landscape scale. Sea urchin predation risk was measured in a 20-day field experiment on tethered individuals placed in three square areas 35×35 m2 in size. Variability of both landscape and habitat structural attributes was assessed at the sampling grain 5×5 m2. Predation risk changed among landscapes, as it was lower where more ‘rocks’, and thus less seagrass, were present. The higher risk was found in the ‘continuous’ P. oceanica rather than in the low-fragmentation, high-fragmentation and rock habitats (p-values = 0.0149, 0.00008, and 0.0001, respectively). Therefore, the expectation that juvenile P. lividus survival would have been higher in the ‘continuous’ seagrass habitat, which would have served as shelter from high fish predation pressure, was not met. Predation risk changed across habitats due to different success between attack types: benthic attacks (mostly from whelks) were overall much more effective than those due to fish activity, the former type being associated with the ‘continuous’ seagrass habitat. Fish predation on juvenile sea urchins on rocks and ‘high-fragmentation’ habitat was less likely than benthic predation in the ‘continuous’ seagrass, with the low seagrass patch complexity increasing benthic activity. Future research should be aimed at investigating, derived from the complex indirect interactions among species, how top-down control in marine reserves can modify seagrass habitat effects.
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- 2016
20. Macroalgal epiphytes of Posidonia oceanica leaves: biogeographic aspects
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Aurora Ulisse, Ivan Guala, Annunziata Esposito, and Cristina Buia Maria
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Global and Planetary Change ,Posidonia ,Ecology ,biology ,Biogeography ,Biodiversity ,biology.organism_classification ,Seagrass ,Mediterranean sea ,Posidonia oceanica ,Epiphyte ,Ecology, Evolution, Behavior and Systematics ,Global biodiversity - Abstract
Biogeographia vol. XXI V - 2003 (Printed October, 31st 2003) Marine biogeography of the Mediterranean Sea: patterns and dynamics of biodiversity Macroalgal epiphytes of Posidonia oceazniccz leaves: biogeographic aspects ANNUNZIATA ESPOSITO, AURORA ULISSE, IVAN GUALA, MARIA CRISTINA BUIA Srzzzione Zoologiaz 1/I. Do/am’ Bent/air Ecology Lzz/aomrmfy — P.ta San Pietro 80077131/9721, Nzzpoli (Italy) E-mzzil: mc[7uz'zz@szn.z't Key words: epiphytes, spatial patterns, biogeographic groups, Pasizlorrizz ocemzim. SUMMARY Epiphyte summer assemblages of Poridazzizz ocezzuim leaves were analyzed at regional (Sardinia) and basin (\X/estern Mediterranean Sea) scales. Along Sardinian coasts, species composition has been evaluated at different sides (East and West), depths (5 and 25 m), and geographical sectors (North, Central—North, Central-South and South), in a total of32 sites. Deriving data from literature, five localities at the same depth were compared, at basin scale. The community structure, at both taxonomic and biogeographic level. was analyzed to reveal spatial patterns in epiphyte assemblages. At smaller scale, the number of species varied significantly with side, sector and site, while the assemblage composition did not; the biogeographic composition did not show significant differences because of the relevant influence of Subcosmopolitan and Cosmopolitan taxa. At basin scale taxonomic and biogeographic composition of epiphyte communities did not change according to a latitudinal gradient at least dealing with Western central Mediterranean Sea. INTRODUCTION Epiphytic algae are a diverse flora growing on host seagrasses. Their importance to Posidonzkz ocezzrziczz ecosystem functioning in terms of food supply for macroherbivore—detritivore species is well recognized (Garnbi et al., 1992; Buia et al., 2000; Zupo, 2001). In some cases the grazing impact was found to have a stabilizing effect on the system, as the epiphytic community may negatively influence the leaf production of seagrasses (Orth and Van Montfrans, 1984). However, this latter process was never confirmed in P. ocezmiczz and it could be considered as an indicator ofenvironmental change in the functioning of the system. A predictable succession and zonation ofepiphytic taxon and assemblages are identifiable on seagrass leaves, according to the blade age—gradient and life—tirne
- Published
- 2003
21. Interannual and decadal variability in posidonia oceanica
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Buia, M. C., Flagella, S., ivan guala, Gravina, T., Flagella, M. M., and Cigliano, M. M.
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