Substitution and phase shift within the Posidonia oceanica seagrass meadows of NW Mediterranean Sea

Abstract. The role of seagrass, Posidonia oceanica, meadows as a source of transparent exopolymer particles (TEPs) to Mediterranean coastal waters was tested by comparing the TEP dynamics in two adjacent coastal waters in the oligotrophic NW Mediterranean Sea, one characterized by oligotrophic open-sea waters and the other accumulating seagrass leaf litter, together with an experimental examination of TEP release by seagrass litter. TEP concentrations ranged from 4.6 to 90.6 µg XG (xanthan gum) Eq L−1, with mean (±SE) values of 38.7 (± 2.02) µg XG Eq L−1 in the site devoid of seagrass litter, whereas the coastal beach site accumulating leaf litter had > 10-fold mean TEP concentrations of 487.02 (± 72.8) µg XG Eq L−1. Experimental evaluation confirmed high rates of TEP production by P. oceanica litter, allowing calculations of the associated TEP yield. We demonstrated that P. oceanica is an important source of TEPs to the Mediterranean Sea, contributing an estimated 76 Gg C as TEPs annually. TEP release by P. oceanica seagrass explains the elevated TEP concentration relative to the low chlorophyll a concentration in the Mediterranean Sea.

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Seagrass as major source of transparent exopolymer particles in the oligotrophic Mediterranean coast

10.5194/bg-2016-558 ◽

2017 ◽

Cited By ~ 1

Author(s):

Francesca Iuculano ◽

Carlos M. Duarte ◽

Núria Marbà ◽

Susana Augustí

Keyword(s):

Mediterranean Sea ◽

Leaf Litter ◽

Coastal Waters ◽

Posidonia Oceanica ◽

Mediterranean Coast ◽

Transparent Exopolymer Particles ◽

Coastal Beach ◽

Nw Mediterranean ◽

The Mediterranean ◽

Nw Mediterranean Sea

Abstract. The role of seagrass, Posidonia oceanica, meadows as a source of transparent exopolymer particles (TEP) to Mediterranean coastal waters was tested by comparing the TEP dynamics in two adjacent coastal waters in the oligotrophic NW Mediterranean Sea, one characterized by oligotrophic open-sea waters and the other accumulating seagrass leaf litter, together with an experimental examination of TEP release by seagrass litter. TEP concentrations ranged from 4.6 µg XG Eq L−1 to 90.6 µg XG Eq L−1, with mean (±SE) values of 38.7 (±2.02) µg XG Eq L−1 in the site devoid of seagrass litter, whereas the coastal beach site accumulating leaf litter had > 10-fold mean TEP concentrations of 487.02 (±72.8) µg XG Eq L−1 . Experimental evaluation confirmed high rates of TEP production by P. oceanica litter, allowing calculations of the associated TEP yield. We demonstrated that P. oceanica is an important source of TEP to the Mediterranean Sea, contributing an estimated 0.10 Tg C as TEP annually. TEP release by P. oceanica seagrass explains the elevated TEP concentration relative to the low chlorophyll a concentration in the Mediterranean Sea.

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Main drivers of spatial change in the biomass of commercial species between summer and winter in the NW Mediterranean Sea

Marine Environmental Research ◽

10.1016/j.marenvres.2020.105227 ◽

2020 ◽

pp. 105227

Author(s):

Elena Lloret-Lloret ◽

Maria Grazia Pennino ◽

Daniel Vilas ◽

José María Bellido ◽

Joan Navarro ◽

...

Keyword(s):

Mediterranean Sea ◽

Spatial Change ◽

Commercial Species ◽

Nw Mediterranean ◽

Nw Mediterranean Sea

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Posidonia oceanica as a Source of Chromophoric Dissolved Organic Matter for the Oligotrophic NW Mediterranean Coast

Journal of Marine Science and Engineering ◽

10.3390/jmse8110911 ◽

2020 ◽

Vol 8 (11) ◽

pp. 911

Author(s):

Francesca Iuculano ◽

Carlos M. Duarte ◽

Jaime Otero ◽

Xosé Antón Álvarez-Salgado ◽

Susana Agustí

Keyword(s):

Organic Matter ◽

Dissolved Organic Matter ◽

Rocky Shore ◽

Posidonia Oceanica ◽

Mediterranean Coast ◽

Balearic Islands ◽

Chromophoric Dissolved Organic Matter ◽

Absorption Increase ◽

Seagrass Meadows ◽

Nw Mediterranean

Posidonia oceanica is a well-recognized source of dissolved organic matter (DOM) derived from exudation and leaching of seagrass leaves, but little is known about its impact on the chromophoric fraction of DOM (CDOM). In this study, we monitored for two years the optical properties of CDOM in two contrasting sites in the Mallorca Coast (Balearic Islands). One site was a rocky shore free of seagrass meadows, and the second site was characterized by the accumulation of non-living seagrass material in the form of banquettes. On average, the integrated color over the 250–600 nm range was almost 6-fold higher in the beach compared with the rocky shore. Furthermore, the shapes of the CDOM spectra in the two sites were also different. A short incubation experiment suggested that the spectral differences were due to leaching from P. oceanica leaf decomposition. Furthermore, occasionally the spectra of P. oceanica was distorted by a marked absorption increase at wavelength < 265 nm, presumably related to the release of hydrogen sulfide (HS−) associated with the anaerobic decomposition of seagrass leaves within the banquettes. Our results provide the first evidence that P. oceanica is a source of CDOM to the surrounding waters.

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Environmental occurrence of phthalate and organophosphate esters in sediments across the Gulf of Lion (NW Mediterranean Sea)

The Science of The Total Environment ◽

10.1016/j.scitotenv.2020.143412 ◽

2020 ◽

pp. 143412

Author(s):

Nigar Alkan ◽

Ali Alkan ◽

Javier Castro-Jiménez ◽

Florian Royer ◽

Laure Papillon ◽

...

Keyword(s):

Mediterranean Sea ◽

Organophosphate Esters ◽

Gulf Of Lion ◽

Nw Mediterranean ◽

Nw Mediterranean Sea

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Composition and provenance of terrigenous organic matter transported along submarine canyons in the Gulf of Lion (NW Mediterranean Sea)

Progress In Oceanography ◽

10.1016/j.pocean.2013.07.013 ◽

2013 ◽

Vol 118 ◽

pp. 81-94 ◽

Cited By ~ 13

Author(s):

Catalina Pasqual ◽

Miguel A. Goñi ◽

Tommaso Tesi ◽

Anna Sanchez-Vidal ◽

Antoni Calafat ◽

...

Keyword(s):

Organic Matter ◽

Mediterranean Sea ◽

Submarine Canyons ◽

Terrigenous Organic Matter ◽

Gulf Of Lion ◽

Nw Mediterranean ◽

Nw Mediterranean Sea

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7000 years of paleostorm activity in the NW Mediterranean Sea in response to Holocene climate events

Quaternary Research ◽

10.1016/j.yqres.2011.09.002 ◽

2012 ◽

Vol 77 (1) ◽

pp. 1-11 ◽

Cited By ~ 103

Author(s):

Pierre Sabatier ◽

Laurent Dezileau ◽

Christophe Colin ◽

Louis Briqueu ◽

Frédéric Bouchette ◽

...

Keyword(s):

Mediterranean Sea ◽

North Atlantic ◽

Clay Mineralogy ◽

Mediterranean Coast ◽

Ice Age ◽

Storm Activity ◽

The North ◽

Nw Mediterranean ◽

The North Atlantic ◽

Nw Mediterranean Sea

A high-resolution record of paleostorm events along the French Mediterranean coast over the past 7000 years was established from a lagoonal sediment core in the Gulf of Lions. Integrating grain size, faunal analysis, clay mineralogy and geochemistry data with a chronology derived from radiocarbon dating, we recorded seven periods of increased storm activity at 6300–6100, 5650–5400, 4400–4050, 3650–3200, 2800–2600, 1950–1400 and 400–50 cal yr BP (in the Little Ice Age). In contrast, our results show that the Medieval Climate Anomaly (1150–650 cal yr BP) was characterised by low storm activity.The evidence for high storm activity in the NW Mediterranean Sea is in agreement with the changes in coastal hydrodynamics observed over the Eastern North Atlantic and seems to correspond to Holocene cooling in the North Atlantic. Periods of low SSTs there may have led to a stronger meridional temperature gradient and a southward migration of the westerlies. We hypothesise that the increase in storm activity during Holocene cold events over the North Atlantic and Mediterranean regions was probably due to an increase in the thermal gradient that led to an enhanced lower tropospheric baroclinicity over a large Central Atlantic-European domain.

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