Effect of pollution on the bacterial community structure in the coastal waters of the eastern Mediterranean sea

Abstract. We examined the vertical and temporal dynamics of nutrients, ectoenzymatic activities under late summer-fall transition period (September–October 2004) in NW Mediterranean Sea in relation to temporal change in factors limiting bacterial production. The depth of the mixed layer (12.8±5.3 m) was extremely stable until the onset of the destratification period after 11 October, creating a zone where diffusion of nutrient from the much deeper phosphacline (69±12 m) and nitracline (50±8 m) was probably strongly limited. However during the second half of the cruise, a shallowing of nutriclines occured, particularly marked for nitracline. Hence, the nitrate to phosphate ratio within the mixed layer, although submitted to a high short term variability, shifted the last week of the cruise from 1.1±1.2 to 4.6±3.8, and nitrate increased by a factor 2 (0.092±0.049 μM). A corresponding switch from more than one limitation (PN) to P-only limitation of bacterial production was observed during the month as detected by enrichment bioassays. Differences in the identity of the limiting nutrient in surface (5 m: N and P at the beginning, strictly P at the end of the study) versus 80 m (labile carbon) influence greatly bacterial community structure shift between these two layers. The two communities (5 and 80 m) reacted rapidly (24 h) to changes in nutrient concentrations by drastic modification of total and active population assemblages resulting in changes in activity. For bacterial production values less than 10 ng C l−1h−1 (associated to deeper layers), aminopeptidase and lipase exhibited higher activity relative to production whereas phosphatase varied in the same proportions than BP on the range of activities tested. Our results illustrate the effect of bottom-up control on bacterial community structure and activities in the epipelagic NW Mediterranean Sea.

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First occurrence of Scarus ghobban (Actinopterygii: Scaridae) in the coastal waters of Cyprus (Eastern Mediterranean Sea)

Mediterranean Marine Science ◽

10.12681/mms.82 ◽

2010 ◽

Vol 11 (2) ◽

pp. 353 ◽

Cited By ~ 2

Author(s):

G. IOANNOU ◽

N. MICHAILIDIS ◽

A. LOUCAIDES ◽

I. MANITARAS

Keyword(s):

Mediterranean Sea ◽

Coastal Waters ◽

Eastern Mediterranean ◽

Eastern Mediterranean Sea ◽

First Occurrence ◽

Scarus Ghobban

The first occurrence of the Indo-Pacific blue-barred parrotfish (Scarus ghobban) in the coastal waters of Cyprus is reported. The finding corroborates the establishment of this Lessepsian immigrant along the Levantine coasts.

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Spatial scales of bacterial community diversity at cold seeps (Eastern Mediterranean Sea)

The ISME Journal ◽

10.1038/ismej.2014.217 ◽

2014 ◽

Vol 9 (6) ◽

pp. 1306-1318 ◽

Cited By ~ 42

Author(s):

Petra Pop Ristova ◽

Frank Wenzhöfer ◽

Alban Ramette ◽

Janine Felden ◽

Antje Boetius

Keyword(s):

Bacterial Community ◽

Mediterranean Sea ◽

Eastern Mediterranean ◽

Spatial Scales ◽

Community Diversity ◽

Cold Seeps ◽

Eastern Mediterranean Sea ◽

Bacterial Community Diversity

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Two-way bioinvasion: tracking the neritic non-native cyclopoid copepods Dioithona oculata and Oithona davisae (Oithonidae) in the Eastern Mediterranean Sea

Mediterranean Marine Science ◽

10.12681/mms.26036 ◽

2021 ◽

Vol 22 (3) ◽

pp. 586

Author(s):

XIMENA VELASQUEZ ◽

ARSENIY R. MOROV ◽

TUBA TERBIYIK KURT ◽

DALIT MERON ◽

TAMAR GUY-HAIM

Keyword(s):

Water Temperature ◽

Mediterranean Sea ◽

Coastal Waters ◽

Eastern Mediterranean ◽

Morphological Characteristics ◽

Eastern Mediterranean Sea ◽

Levantine Sea ◽

Oithona Davisae ◽

Introduced Range ◽

Almost All

Accelerated anthropogenic changes in the Eastern Mediterranean Sea (EMS) have facilitated the introduction, spread and establishment of invasive copepod species in this region. Here, we report the introduction of two non-native cyclopoid copepods Dioithona oculata and Oithona davisae for the first time in the Israeli coastal waters and describe their temporal variability. The species were identified by morphological characteristics, DNA barcoding and phylogenetic inference. Molecular identification and phylogenetic analysis supported the taxonomical identification, nevertheless, showed cryptic speciation within D. oculata, separating the Western Pacific and EMS clades. In the Israeli coastal waters, D. oculata presented a temporally restricted occurrence, appearing from September 2019 to December 2019 (30.0±0.7 – 21.0±1.1 °C) and October 2020 (28.0±0.7 °C). The highest abundances of D. oculata occurred in the autumn (October 2019 and 2020), when the water temperature reached 28.0 °C (7 and 10 ind. m-3, respectively). The lowest abundance occurred in December 2019 (0.35 ind. m-3), when the water temperature decreased to 21.0 °C, indicating that the thermal affinity of D. oculata for warm-temperate conditions, for reproduction and the maintenance of viable populations, has persisted in the introduced range. In contrast, O. davisae appeared almost all year around (17.0±0.5 – 28.0±0.7 °C). This species demonstrated peaks in abundance both in October 2019 and October 2020, when the water temperature reached 28.0 °C (406 and 92 ind. m-3), as well as when the temperature decreased to 17.0 °C (31 ind. m-3, February 2020), confirming its wide eurythermal tolerance. Based on our findings and previous observations, we suggest that D. oculata may have invaded the EMS through the Suez Canal and is now at the onset of its spread in the Mediterranean Sea, whereas O. davisae has been introduced via shipping, likely from the Northeast Atlantic, widely spreading and successfully establishing viable populations across the entire Mediterranean Sea, until the coastal Levantine Sea.

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Microbial communities in an ultra-oligotrophic sea are more affected by season than by distance from shore

10.1101/2020.04.17.044305 ◽

2020 ◽

Author(s):

Markus Haber ◽

Dalit Roth Rosenberg ◽

Maya Lalzar ◽

Ilia Burgsdorf ◽

Kumar Saurav ◽

...

Keyword(s):

Community Structure ◽

Microbial Community ◽

Microbial Communities ◽

Mediterranean Sea ◽

Community Composition ◽

Eastern Mediterranean ◽

Microbial Community Composition ◽

Eastern Mediterranean Sea ◽

South Eastern ◽

Structure And Activity

AbstractMarine microbial communities vary seasonally and spatially, but these two factors are rarely addressed together. We studied temporal and spatial patterns of the microbial community structure and activity along a coast to offshore transect from the Israeli coast of the Eastern Mediterranean Sea (EMS) over six cruises, in three seasons of two consecutive years. The ultra-oligotrophic status of the South Eastern Mediterranean Sea was reflected in the microbial community composition that was dominated by oligotrophic microbial groups such as SAR11 throughout the year, even at the most coastal station sampled. Seasons affected microbial communities much more than distance from shore explaining about half of the observed variability in the microbial community, compared to only about 6% that was explained by station. However, the most coastal site differed significantly in community structure and activity from the three further offshore stations in early winter and summer, but not in spring. Our data on the microbial community composition and its seasonality from a transect into the South Eastern Levantine basin support the notion that the EMS behaves similar to open gyres rather than an inland sea.

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Distribution Patterns of Floating Microplastics in Open and Coastal Waters of the Eastern Mediterranean Sea (Ionian, Aegean, and Levantine Seas)

Frontiers in Marine Science ◽

10.3389/fmars.2021.699000 ◽

2021 ◽

Vol 8 ◽

Author(s):

Argyro Adamopoulou ◽

Christina Zeri ◽

Francesca Garaventa ◽

Chiara Gambardella ◽

Christos Ioakeimidis ◽

...

Keyword(s):

Mediterranean Sea ◽

Coastal Waters ◽

Spectroscopic Analysis ◽

Eastern Mediterranean ◽

Distribution Patterns ◽

Sea Surface ◽

Morphological Properties ◽

Eastern Mediterranean Sea ◽

Surface Circulation ◽

Open Sea

Microplastic pollution is a pervasive anthropogenic phenomenon at the ocean surface. Numerous studies have been performed worldwide; nevertheless, the distribution patterns, morphological properties, and sources of origin in the Eastern Mediterranean Sea are still poorly explored. The purpose of this study is to investigate the distribution patterns of surface floating microplastics (MPs) in the Ionian, Aegean, and Levantine Seas in relation to their sources and sea surface circulation. In total, eighty-four samples were collected using manta nets from 2014 to 2020, covering open waters, coastal waters, and enclosed gulfs (Corfu and Saronikos). MPs concentration measurements revealed high variability ranging from 0.012 to 1.62 items m–2 and did not present maximum concentrations close to MPs hotspot areas. The presence of sea surface slicks, as recorded visually during our samplings, seems to play a key role on the distribution pattern of MPs, and highest concentrations were recorded in samples affected by these formations. The dominant MPs shape type identified were fragments (50–60%), whilst filaments (1–23%), films (3–26%), and foams (0–34%) varied among the studied areas. The majority of MPs in open waters had sizes ≤2 mm peaking between 0.6 and 1.4 mm. Spectroscopic analysis of MPs revealed the presence of 11 polymer types in both open sea and gulfs; the most abundant type was polyethylene (PE), followed by polypropylene (PP), and polystyrene (PS). The relative abundance of polymer types was more diverse in Saronikos Gulf, compared to the open sea due to the proximity to major urban and industrial sources. Our findings suggest that the vicinity to coastal population centers determined the properties, size and polymer types of MPs and highlight that MPs concentrations are affected significantly by local oceanographic conditions, such as surface slicks.

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210Po and 210Pb concentration in zooplankton of the Syrian coastal waters (eastern Mediterranean Sea)

Mediterranean Marine Science ◽

10.12681/mms.19072 ◽

2019 ◽

Vol 20 (2) ◽

pp. 320 ◽

Cited By ~ 1

Author(s):

MOHAMMAD SAID AL-MASRI ◽

SAMER MAMISH ◽

MOHAMMAD ABDEL-HALEEM ◽

HANI HANI DURGHAM

Keyword(s):

Mediterranean Sea ◽

Coastal Waters ◽

Concentration Ratio ◽

Eastern Mediterranean ◽

Reference Database ◽

Eastern Mediterranean Sea ◽

Marine Zooplankton ◽

Activity Concentrations ◽

210Pb Activity ◽

Average Activity

210Po and 210Pb activity concentrations and their concentration ratio (CR) in marine zooplankton collected for the first time from the Syrian coastal waters (the eastern Mediterranean Sea) have been determined. The average activity concentrations of 210Po and 210Pb were 243±36 and 26.4±4.3 Bqkg-1 dw. The 210Po/210Pb activity ratio was found to be more than one in all zooplankton samples with an average of 9.2 (8.4 to 10), which indicates that the accumulation of 210Po in zooplankton does not come from the decay of the 210Pb only, and reflects a preferential bioaccumulation of 210Po over 210Pb. In addition, the Concentration Ratio (CR) for 210Po and 210Pb reached 104 and 103, respectively. This study will contribute to the radioecological reference database for zooplankton in the Mediterranean Sea.

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