Spatio-temporal patterns of macrourid fish species in the northern Mediterranean Sea

The present study describes for the first time the spatial distribution of five macrourid species throughout the Mediterranean Sea and analyses depth, geographical and time-related trends regarding their abundance, biomass and mean fish weight. The data were collected as part of the MEDITS annual bottom trawl survey carried out by several European Mediterranean countries from 1994 to 2015, using the same standardized gear and sampling protocol. The most represented species in terms of abundance and biomass was Coelorinchus caelorhincus. The bathymetric trend was different for each species. The shallowest occurring species was C. caelorhincus, followed by Hymenocephalus italicus and Nezumia sclerorhynchus, while Nezumia aequalis and Trachyrincus scabrus were the deepest. Overall, the mean weight of all the species increased with depth. C. caelorhincus and H. italicus occurred in the entire study area: the first species showed relatively high catches in most areas, while the second was more abundant in the central and easternmost areas. N. aequalis and T. scabrus were mainly reported in the western basin, and N. sclerorhynchus in the central-eastern areas of the Mediterranean. An increasing inter-annual trend in abundance was only detected for C. caelorhincus and N. sclerorhynchus, while variable fluctuations were observed in the other species.

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Bio-optical characterization of subsurface chlorophyll maxima in the Mediterranean Sea from a Biogeochemical-Argo float database

10.5194/bg-2018-367 ◽

2018 ◽

Author(s):

Marie Barbieux ◽

Julia Uitz ◽

Bernard Gentili ◽

Orens Pasqueron de Fommervault ◽

Alexandre Mignot ◽

...

Keyword(s):

Mediterranean Sea ◽

Chlorophyll Concentration ◽

Environmental Parameters ◽

Western Basin ◽

Different Types ◽

The Mediterranean ◽

Spatio Temporal ◽

The Vertical Distribution

Abstract. As commonly observed in oligotrophic stratified waters, a Subsurface (or Deep) Chlorophyll Maximum (SCM) frequently characterizes the vertical distribution of phytoplankton chlorophyll in the Mediterranean Sea. Occurring far from the surface layer seen by ocean color satellites, SCMs are difficult to observe with adequate spatio-temporal resolution and their biogeochemical impact remains unknown. BioGeochemical-Argo (BGC-Argo) profiling floats represent appropriate tools for studying the dynamics of SCMs. Based on data collected from 36 BGC-Argo floats deployed in the Mediterranean Sea, our study aims to address two main questions: (1) What are the different types of SCMs in Mediterranean Sea? (2) Which environmental factors control their occurrence and dynamics? First, we analyzed the seasonal and regional variations of the chlorophyll concentration (Chla), particulate backscattering coefficient (bbp), a proxy of the Particulate Organic Carbon (POC), and environmental parameters (PAR and nitrates) within the SCM layer over the Mediterranean basin. The vertical profiles of Chla and bbp were then statistically classified, and the seasonal occurrence of each of the different types of SCMs quantified. Finally, a case study was performed on two contrasted regions and the environmental conditions at depth were further investigated to understand which parameter controls the SCMs. In the Eastern Basin, SCMs result, at a first order, from photoacclimation process. Conversely, SCMs in the Western Basin reflect a biomass increase at depth benefiting from both light and nitrate resources. Our results also suggest that a variety of intermediate types of SCMs are encountered between these two end-member situations.

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The general specifications of the MEDITS surveys

Scientia Marina ◽

10.3989/scimar.2002.66s29 ◽

2002 ◽

Vol 66 (S2) ◽

pp. 9 ◽

Cited By ~ 193

Author(s):

Jacques A. Bertrand ◽

Luis Gil de Sola ◽

Costas Papaconstantinou ◽

Giulio Relini ◽

Arnauld Souplet

Keyword(s):

European Commission ◽

Mediterranean Sea ◽

Biological Data ◽

Bottom Trawl ◽

Trawl Survey ◽

Bottom Trawl Survey ◽

Mediterranean Countries ◽

The Mediterranean

An international bottom trawl survey was designed from a European Commission´s initiative to produce biological data on the demersal resources in the Mediterranean Sea. Nine Mediterranean countries are associated in the programme, which covers all the trawlable areas along their coasts from 10 to 800 m depth. From 1994 to 2000, one survey was carried out each year, applying common standardized protocols. Seven yearly surveys have therefore been done, with a total of 7,500 stations prospected. This paper presents the methods adopted to carry out the surveys.

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Bio-optical characterization of subsurface chlorophyll maxima in the Mediterranean Sea from a Biogeochemical-Argo float database

Biogeosciences ◽

10.5194/bg-16-1321-2019 ◽

2019 ◽

Vol 16 (6) ◽

pp. 1321-1342 ◽

Cited By ~ 13

Author(s):

Marie Barbieux ◽

Julia Uitz ◽

Bernard Gentili ◽

Orens Pasqueron de Fommervault ◽

Alexandre Mignot ◽

...

Keyword(s):

Mediterranean Sea ◽

Chlorophyll Concentration ◽

Environmental Parameters ◽

Western Basin ◽

Chl A ◽

Different Types ◽

The Mediterranean ◽

Spatio Temporal ◽

The Vertical Distribution

Abstract. As commonly observed in oligotrophic stratified waters, a subsurface (or deep) chlorophyll maximum (SCM) frequently characterizes the vertical distribution of phytoplankton chlorophyll in the Mediterranean Sea. Occurring far from the surface layer “seen” by ocean colour satellites, SCMs are difficult to observe with adequate spatio-temporal resolution and their biogeochemical impact remains unknown. Biogeochemical-Argo (BGC-Argo) profiling floats represent appropriate tools for studying the dynamics of SCMs. Based on data collected from 36 BGC-Argo floats deployed in the Mediterranean Sea, our study aims to address two main questions. (1) What are the different types of SCMs in the Mediterranean Sea? (2) Which environmental factors control their occurrence and dynamics? First, we analysed the seasonal and regional variations in the chlorophyll concentration (Chl a), particulate backscattering coefficient (bbp), a proxy of the particulate organic carbon (POC) and environmental parameters (photosynthetically active radiation and nitrates) within the SCM layer over the Mediterranean Basin. The vertical profiles of Chl a and bbp were then statistically classified and the seasonal occurrence of each of the different types of SCMs quantified. Finally, a case study was performed on two contrasted regions and the environmental conditions at depth were further investigated to understand the main controls on the SCMs. In the eastern basin, SCMs result, at a first order, from a photoacclimation process. Conversely, SCMs in the western basin reflect a biomass increase at depth benefiting from both light and nitrate resources. Our results also suggest that a variety of intermediate types of SCMs are encountered between these two endmember situations.

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Distribution of Mullus barbatus and M. surmuletus (Osteichthyes: Perciformes) in the Mediterranean continental shelf: implications for management

Scientia Marina ◽

10.3989/scimar.2002.66s239 ◽

2002 ◽

Vol 66 (S2) ◽

pp. 39 ◽

Cited By ~ 27

Author(s):

George Tserpes ◽

Fabio Fiorentino ◽

Dino Levi ◽

Angelo Cau ◽

Matteo Murenu ◽

...

Keyword(s):

Mediterranean Sea ◽

Random Sampling ◽

Temporal Distribution ◽

Stratified Random Sampling ◽

Trawl Survey ◽

Mullus Barbatus ◽

Stock Recruitment ◽

The Mediterranean ◽

Spatio Temporal ◽

Selection Of

The present work attempts to study the spatio-temporal distribution of Mullus barbatus and M. surmuletus in the Mediterranean Sea by using a time series of data from an international bottom trawl survey that covered a wide area of the Mediterranean Sea. The experimental surveys were accomplished annually from 1994 to 2000 on approximately 1000 pre-defined sampling stations distributed in 15 major areas. Selection of stations was based on a depth-stratified random sampling scheme that included five depth strata: 10-50, 50-100, 100-200, 200-500 and 500-800 m. The examined species were found throughout the studied region, mostly in depths down to 200 m. Abundance differences among major areas were found to be statistically significant and were attributed to the different exploitation patterns, as well as the different abiotic and biotic conditions prevailing in each area. Although both species undergo high fishing pressure, results did not demonstrate any decreasing trends in their abundance indices suggesting the existence of a good stock-recruitment relationship over the studied period. However, the dominance of young fish that has been found, makes the stocks highly vulnerable to recruitment changes; hence protection of spawning and nursery areas seems to be essential for their conservation.

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Spatio-temporal variability in the distribution pattern of anglerfish species in the Mediterranean Sea

Scientia Marina ◽

10.3989/scimar.04966.11a ◽

2020 ◽

Vol 83 (S1) ◽

pp. 129 ◽

Cited By ~ 2

Author(s):

Elena Barcala ◽

Jose Maria Bellido ◽

Andrea Bellodi ◽

Pierluigi Carbonara ◽

Roberto Carlucci ◽

...

Keyword(s):

Mediterranean Sea ◽

Temporal Distribution ◽

Aegean Sea ◽

Boosted Regression Trees ◽

Trawl Survey ◽

Depth Range ◽

General Terms ◽

Sea Bottom ◽

The Mediterranean ◽

Spatio Temporal

The Mediterranean distributions of two species of anglerfish, the blackbellied anglerfish (Lophius budegassa) and the white anglerfish (Lophius piscatorius), were analysed from trawl survey data (MEDITS project – Spain, France, Italy and Greece) from 2006 to 2015 implementing a Delta model approach with residuals autocovariate boosted regression trees. Sea bottom temperature (SBT), sea bottom salinity (SBS), bathymetry, slope of the seabed and distance to the coast were considered possible predictors. The results show that the locations with a higher presence, abundance and biomass of L. budegassa are those with a depth range between 150 to 300 m, with an SBT range between 17.5 and 18.5°C, and SBS of 37-38 PSU. Similarly, L. piscatorius shows a higher probability of presence, abundance and biomass in location with a bathymetry range of 200-400 m, an SBT of 17.5°C to 18.5°C and an SBS of 36.5 to 37.5. Our results identify preference habitats for the anglerfishes in the Mediterranean Sea such as the Aegean Sea, the Gulf of Lions, south and southeast Spain and the northwestern Ionian Sea. In general terms, these findings enhance our understanding of the differences in the spatio-temporal distribution of these two species, providing useful information that can help their fisheries management and conservation.

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First Description of Two Sequence Type 2 Acinetobacter baumannii Isolates Carrying OXA-23 Carbapenemase in Pagellus acarne Fished from the Mediterranean Sea near Bejaia, Algeria

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.02384-15 ◽

2016 ◽

Vol 60 (4) ◽

pp. 2513-2515 ◽

Cited By ~ 16

Author(s):

Soumia Brahmi ◽

Abdelaziz Touati ◽

Axelle Cadière ◽

Nassima Djahmi ◽

Alix Pantel ◽

...

Keyword(s):

Acinetobacter Baumannii ◽

Mediterranean Sea ◽

Sequence Type ◽

Content Type ◽

Carbapenem Resistant ◽

Selective Agar ◽

Agar Media ◽

The Mediterranean ◽

First Time

ABSTRACTTo determine the occurrence of carbapenem-resistantAcinetobacter baumanniiin fish fished from the Mediterranean Sea near the Bejaia coast (Algeria), we studied 300 gills and gut samples that had been randomly and prospectively collected during 1 year. After screening on selective agar media, using PCR arrays and whole-genome sequencing, we identified for the first time two OXA-23-producingA. baumanniistrains belonging to the widespread sequence type 2 (ST2)/international clone II and harboring aminoglycoside-modifying enzymes [aac(6′)-Ib andaac(3′)-I genes].

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Ecology of aerobic anoxygenic phototrophic bacteria along an oligotrophic gradient in the Mediterranean Sea

Biogeosciences ◽

10.5194/bg-8-973-2011 ◽

2011 ◽

Vol 8 (4) ◽

pp. 973-985 ◽

Cited By ~ 28

Author(s):

D. Lamy ◽

C. Jeanthon ◽

M. T. Cottrell ◽

D. L. Kirchman ◽

F. Van Wambeke ◽

...

Keyword(s):

Mediterranean Sea ◽

Bacterial Growth ◽

Growth Response ◽

Anoxygenic Phototrophic Bacteria ◽

Carbon Limitation ◽

Organic Substrates ◽

Western Basin ◽

Eastern Basin ◽

Nutrient Additions ◽

The Mediterranean

Abstract. Aerobic anoxygenic phototrophic (AAP) bacteria are photoheterotrophic prokaryotes able to use both light and organic substrates for energy production. They are widely distributed in coastal and oceanic environments and may contribute significantly to the carbon cycle in the upper ocean. To better understand questions regarding links between the ecology of these photoheterotrophic bacteria and the trophic status of water masses, we examined their horizontal and vertical distribution and the effects of nutrient additions on their growth along an oligotrophic gradient in the Mediterranean Sea. Concentrations of bacteriochlorophyll-a (BChl-a) and AAP bacterial abundance decreased from the western to the eastern basin of the Mediterranean Sea and were linked with concentrations of chlorophyll-a, nutrient and dissolved organic carbon. Inorganic nutrient and glucose additions to surface seawater samples along the oligotrophic gradient revealed that AAP bacteria were nitrogen- and carbon-limited in the ultraoligotrophic eastern basin. The intensity of the AAP bacterial growth response generally differed from that of the total bacterial growth response. BChl-a quota of AAP bacterial communities was significantly higher in the eastern basin than in the western basin, suggesting that reliance on phototrophy varied along the oligotrophic gradient and that nutrient and/or carbon limitation favors BChl-a synthesis.

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The spatio-temporal distribution of lightning over Israel and the neighboring area and its relation to regional synoptic systems

Natural Hazards and Earth System Science ◽

10.5194/nhess-11-2125-2011 ◽

2011 ◽

Vol 11 (8) ◽

pp. 2125-2135 ◽

Cited By ~ 21

Author(s):

S. Shalev ◽

H. Saaroni ◽

T. Izsak ◽

Y. Yair ◽

B. Ziv

Keyword(s):

Spatial Distribution ◽

Mediterranean Sea ◽

Temporal Distribution ◽

Lightning Activity ◽

Eastern Coast ◽

Synoptic Situation ◽

Lightning Flash ◽

The Mediterranean ◽

Spatio Temporal ◽

Neighboring Area

Abstract. The spatio-temporal distribution of lightning flashes over Israel and the neighboring area and its relation to the regional synoptic systems has been studied, based on data obtained from the Israel Lightning Location System (ILLS) operated by the Israel Electric Corporation (IEC). The system detects cloud-to-ground lightning discharges in a range of ~500 km around central Israel (32.5° N, 35° E). The study period was defined for annual activity from August through July, for 5 seasons in the period 2004–2010. The spatial distribution of lightning flash density indicates the highest concentration over the Mediterranean Sea, attributed to the contribution of moisture as well as sensible and latent heat fluxes from the sea surface. Other centers of high density appear along the coastal plain, orographic barriers, especially in northern Israel, and downwind from the metropolitan area of Tel Aviv, Israel. The intra-annual distribution shows an absence of lightning during the summer months (JJA) due to the persistent subsidence over the region. The vast majority of lightning activity occurs during 7 months, October to April. Although over 65 % of the rainfall in Israel is obtained during the winter months (DJF), only 35 % of lightning flashes occur in these months. October is the richest month, with 40 % of total annual flashes. This is attributed both to tropical intrusions, i.e., Red Sea Troughs (RST), which are characterized by intense static instability and convection, and to Cyprus Lows (CLs) arriving from the west. Based on daily study of the spatial distribution of lightning, three patterns have been defined; "land", "maritime" and "hybrid". CLs cause high flash density over the Mediterranean Sea, whereas some of the RST days are typified by flashes over land. The pattern defined "hybrid" is a combination of the other 2 patterns. On CL days, only the maritime pattern was noted, whereas in RST days all 3 patterns were found, including the maritime pattern. It is suggested that atmospheric processes associated with RST produce the land pattern. Hence, the occurrence of a maritime pattern in days identified as RST reflects an "apparent RST". The hybrid pattern was associated with an RST located east of Israel. This synoptic type produced the typical flash maximum over the land, but the upper-level trough together with the onshore winds it induced over the eastern coast of the Mediterranean resulted in lightning activity over the sea as well, similar to that of CLs. It is suggested that the spatial distribution patterns of lightning may better identify the synoptic system responsible, a CL, an "active RST" or an "apparent RST". The electrical activity thus serves as a "fingerprint" for the synoptic situation responsible for its generation.

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First record of the sipunculan worm Phascolion (Phascolion) caupo Hendrix, 1975 in the Mediterranean Sea

Mediterranean Marine Science ◽

10.12681/mms.24 ◽

2012 ◽

Vol 13 (1) ◽

pp. 89 ◽

Cited By ~ 7

Author(s):

L.M. FERRERO-VICENTE ◽

A. LOYA-FERNANDEZ ◽

C. MARCO-MENDEZ ◽

E. MARTINEZ-GARCIA ◽

J.I. SAIZ-SALINAS ◽

...

Keyword(s):

Mediterranean Sea ◽

First Record ◽

Western Mediterranean ◽

High Load ◽

San Pedro ◽

Soft Bottoms ◽

The Mediterranean ◽

First Time

Specimens of the sipunculan worm Phascolion (Phascolion) caupo Hendrix, 1975 have been collected for the first time in the Mediterranean Sea, thus increasing the number of known sipunculan species of up to 36 in this area. They were encountered on soft bottoms from the coast of San Pedro del Pinatar (Western Mediterranean). Thirty specimens were collected at a depth ranging from 32.6 to 37.2 m, mainly in sandy substrata with high load of silt and clays. 80% of the individuals were found inhabiting empty shells of gastropods or empty tubes of serpulid polychaetes.

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Is Posidonia oceanica regression a general feature in the Mediterranean Sea?

Mediterranean Marine Science ◽

10.12681/mms.334 ◽

2013 ◽

Vol 14 (1) ◽

pp. 193 ◽

Cited By ~ 23

Author(s):

M. BONACORSI ◽

C. PERGENT-MARTINI ◽

N. BREAND ◽

G. PERGENT

Keyword(s):

Mediterranean Sea ◽

Temporal Evolution ◽

Posidonia Oceanica ◽

Aerial Photographs ◽

Human Pressure ◽

The Mediterranean ◽

Spatio Temporal ◽

Mapping Techniques ◽

Significant Regression ◽

Ancient Maps

Over the last few years, a widespread regression of Posidonia oceanica meadows has been noticed in the Mediterranean Sea. However, the magnitude of this decline is still debated. The objectives of this study are (i) to assess the spatio-temporal evolution of Posidonia oceanica around Cap Corse (Corsica) over time comparing available ancient maps (from 1960) with a new (2011) detailed map realized combining different techniques (aerial photographs, SSS, ROV, scuba diving); (ii) evaluate the reliability of ancient maps; (iii) discuss observed regression of the meadows in relation to human pressure along the 110 km of coast. Thus, the comparison with previous data shows that, apart from sites clearly identified with the actual evolution, there is a relative stability of the surfaces occupied by the seagrass Posidonia oceanica. The recorded differences seem more related to changes in mapping techniques. These results confirm that in areas characterized by a moderate anthropogenic impact, the Posidonia oceanica meadow has no significant regression and that the changes due to the evolution of mapping techniques are not negligible. However, others facts should be taken into account before extrapolating to the Mediterranean Sea (e.g. actually mapped surfaces) and assessing the amplitude of the actual regression.

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