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| Registros recuperados: 17 | |
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| Alami, Sami; Bonacorsi, Marina; Clabaut, Philippe; Jouet, Gwenael; Pergent-martini, Christine; Pergent, Gerard; Sterckeman, Aurore. |
| The regression of seagrass meadows has been extensively studied over the past few years. Although the causes of this regression may be locally natural, it is more generally related to human impact. In the framework of the HalGolo (2010) and CoralCorse (2013) oceanographic campaigns, acoustic data (mosaic of sonograms and bathymetry), validated by field data (Scuba diving, ROV), were acquired at depths of -10 m and -50 m at the NATURA 2000 site “Grand Herbier de la Plaine Orientale” (Western Mediterranean, Corsica). Processing of this data provided evidence of the scale of this mechanical degradation (trawling scars, mooring, etc.), and enabled its quantification with regard to surface area and scar density. The main degradation was observed between -20 and... |
| Tipo: Text |
Palavras-chave: Anthropogenic impact; Corsica; Side Scan Sonar; Posidonia oceanica; Trawling. |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00272/38364/36669.pdf |
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| Gobert, Sylvie; Sartoretto, Stephane; Rico-raimondino, Valerie; Andral, Bruno; Chery, Aurelia; Lejeune, Pierre; Boissery, Pierre. |
| This paper describes the PREI (Posidonia oceanica Rapid Easy Index), a method used to assess the ecological status of seawater along Mediterranean French coasts. The PREI was drawn up according to the requirements of the Water Framework Directive (WFD 2000/60/EC) and was tested on 24 and 18 stations in PACA (Provence-Alpes-Cotes d'Azur) and Corsica, respectively. The PREI is based on five metrics: shoot density, shoot leaf surface area, E/L ratio (epiphytic biomass/leaf biomass), depth of lower limit, and type of this lower limit. The 42 studied stations were classified in the first four levels of status: high, good, moderate and poor. The PREI values ranged between 0.280 and 0.847; this classification is in accordance with our field knowledge and with our... |
| Tipo: Text |
Palavras-chave: Water Frame Directive; Ecological Quality Ratio; Coastal water; Mediterranean Sea; Posidonia oceanica; Seagrass. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6949.pdf |
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| Arnaud-haond, Sophie; Marba, Nuria; Diaz-almela, Elena; Serrao, Ester A.; Duarte, Carlos M.. |
| The diversity-stability relationship is the subject of a long-standing debate in ecology, but the genetic component of diversity has seldom been explored. In this study, we analyzed the interplay between genetic diversity and demographic responses to environmental pressures. This analysis included 30 meadows formed by the Mediterranean endemic seagrass, Posidonia oceanica, showing a wide range of population dynamics ranging from a near equilibrium state to steep decline due to strong environmental pressures close to aquaculture installations. Our results show that sedimentation rates are much better predictors of mortality than clonal or genetic components. An unexpected positive trend was observed between genotypic diversity and mortality, along with a... |
| Tipo: Text |
Palavras-chave: Seagrass; Demography; Clonality; Genetic richness; Diversity-stability; Posidonia oceanica. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00006/11693/8498.pdf |
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| Delgado, O; Ruiz, J; Perez, M; Romero, J; Ballesteros, E. |
| The effects of fish farming on a seagrass (Posidonia oceanica) meadow at Fornells Bay, Minorca (Balearic Islands) were studied. Changes in plant and meadow features (e.g. shoot morphology, shoot density, biomass, rhizome growth, nutrient and soluble sugars concentrations...) in three stations along a transect from a disturbed (organic pollution due to fish cultures) to an undisturbed site were assessed. The fish culture had ceased in 1991; however, seagrass decline, already reported in a previous study for the period 1988-1990, was still taking place at the time of sampling (July 1994). Differences between stations were very clear; the station closest to the fish cages showed reduced shoot density, shoot size, underground biomass, sucrose concentration and... |
| Tipo: Text |
Palavras-chave: Aquaculture; Phanérogame marine; Posidonia oceanica; Eutrophisation; Caractéristique du sédiment; Aquaculture; Seagrass; Posidonia oceanica; Eutrophication; Sediment characteristics. |
| Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00325/43632/43250.pdf |
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| Sammari, Ch.; Hattour, A.; Komatsu, T.; Zarrouk, S; Ben Mustapha, K.; El Abed, A.. |
| In order to study the benthic ecology of the “Messioua banc” (30 NM east off Zarzis, Southern Tunisia), a traditional Tunisian sponge fishing ground, four marine campaigns were conducted with the R/V “Hannibal” from October 2000 to August 2001. The objectives of three of these campaigns were field validation, focusing on the sampling of the Posidonia oceanica meadow and of the sponge population. However the goal of the fourth one, with the use of a multi-beam sonar SEABAT 9001 (Reson Co.), was the mapping of bottom of the surveyed area and the scanning of the Posidonia meadow and its sponge population. The field work allowed the study of sixteen stations covered by a dense meadow extending from 21 to 33 m depth, which present the highest density of... |
| Tipo: Journal Contribution |
Palavras-chave: Shoot density; Sponges; Posidonia oceanica; Http://aims.fao.org/aos/agrovoc/c_49750. |
| Ano: 2002 |
URL: http://hdl.handle.net/1834/226 |
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| Boudouresque, Charles-françois; Blanfuné, Aurélie; Pergent, Gérard; Thibaut, Thierry. |
| Some species of seagrasses (e.g., Zostera marina and Posidonia oceanica) have declined in the Mediterranean, at least locally. Others are progressing, helped by sea warming, such as Cymodocea nodosa and the non-native Halophila stipulacea. The decline of one seagrass can favor another seagrass. All in all, the decline of seagrasses could be less extensive and less general than claimed by some authors. Natural recolonization (cuttings and seedlings) has been more rapid and more widespread than was thought in the 20th century; however, it is sometimes insufficient, which justifies transplanting operations. Many techniques have been proposed to restore Mediterranean seagrass meadows. However, setting aside the short-term failure or half-success of... |
| Tipo: Text |
Palavras-chave: Cymodocea nodosa; Ecosystem diversity; Mediterranean; Natural recolonization; Posidonia oceanica; Seagrass decline; Seagrass restoration; Transplanting; Zostera marina. |
| Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00689/80083/83113.pdf |
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| Mascart, Thibaud; De Troch, Marleen; Remy, François; Michel, Loic; Lepoint, Gilles. |
| Benthic copepods dominate meiofaunal communities from marine phytodetritus, both in terms of numerical abundance and species diversity. Nevertheless, ecological factors driving copepod co-existence and population dynamics are still largely unknown. Here, we aimed to explore feeding habits of four copepod species commonly found in Mediterranean seagrass detritus accumulations, representing distinct eco-morphotypes (planktonic, phytal, epibenthic and mesopsammic). Joint use of fatty acid and stable isotope trophic markers showed that co-occurring harpacticoid copepods have diversified diets. Contrary to what was expected, microphytobenthos does not serve as their main food source. Instead, we found evidence from both techniques that major food items include... |
| Tipo: Text |
Palavras-chave: Macrophytodetritus; Posidonia oceanica; Meiofauna; Stable isotopes; Fatty acids; Isotopic niche; Mixing models; Mediterranean Sea. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00440/55187/60472.pdf |
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| Ben Mustapha, K.; El Abed, A.; Komatsu, T.; Souissi, A.; Sammari, Ch.; Zarrouk, S; Hattour, A.. |
| Several marine campaigns aiming to collect marine demosponges for specific research projects on their taxonomy and biogeography and to study the phenology and distribution of Posidonia oceanica a long the Tunisian coasts were conducted these last 10 years. They allowed a scuba diving prospecting of the infra and circalittoral zones of 555 marine stations. This field work was an occasion to describe some bottom’s associations, to highlight the general state of the main communities, specially the Posidonia and the coralligenous formations, and to draw up a list of their mega benthic species. In general, both biota are well preserved along the Tunisian coasts. except for some black spots, mainly the one of the gulf of Gabes, where detailed analysis showed... |
| Tipo: Journal Contribution |
Palavras-chave: Eponges; Ascidians; Coralligenous; Posidonia oceanica; Bryozoans; Benthos; Sponges. |
| Ano: 2002 |
URL: http://hdl.handle.net/1834/222 |
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| Gobert, S; Kyramarios, M; Lepoint, G; Pergent-martini, C; Bouquegneau, Jm. |
| The biometric parameters (shoot density, length and width of leaves, leaf and epiphyte biomasses, leaf surface) of the P. oceanica meadow present a significant spatial variability at the mesoscale level (100m(2)). All the parameters studied, excepting the number of leaves, decrease according to the depth. The horizontal spatial variations (centrifuge and centripetal distributions) reach a maximum in the shallower areas. The analysis of the microstructures (m(2)) of the meadow has not allowed a relationship to be established between the spatial variations of the biometric parameters and the environmental factors in the sediment (pH, water and organic matter content, red-ox potential, nutrient content). The heterogeneity of the meadow in the Revellata Bay... |
| Tipo: Text |
Palavras-chave: Posidonia oceanica; Distribution spatiale; Biomasse; Sédiment; Phanérogame; Méditerranée; Posidonia oceanica; Spatial distribution; Biomass; Sediment; Seagrass; Mediterranean Sea. |
| Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/00322/43277/43009.pdf |
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| Registros recuperados: 17 | |
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