Marine ecosystems’ responses to climatic and anthropogenic forcings in the Mediterranean

Abstract. We propose a new method to identify and characterise the occurrence of prolonged extreme events in marine ecosystems on the basin scale. There is a growing interest about events that can affect ecosystem functions and services in a changing climate. Our method identifies extreme events as peak occurrences over 99th percentile thresholds computed from local time series and defines an Extreme Events Wave (EEW) as a connected region including these events. The EEWs are characterised by a set of novel indexes, referred to initiation, extent, duration and strength. The indexes, associated to the areas covered by each EEW, are then statistically analysed to highlight the main features of the EEWs on the considered domain. We applied the method to the winter-spring daily chlorophyll field of a validated multidecadal hindcast provided by a coupled hydrodynamic-biogeochemical model of the Mediterranean open-sea ecosystem, with 1/12° horizontal resolution. This allowed to identify the maxima of chlorophyll as exceptionally high and prolonged blooms and to characterise their phenomenology in the period 1994–2012. A fuzzy k-means cluster analysis on the EEWs indexes provided a bio-regionalisation of the Mediterranean Sea associated to the occurrence of chlorophyll EEWs with different regimes.

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Distribution and host diversity of Amoebophryidae parasites across oligotrophic waters of the Mediterranean Sea

Biogeosciences ◽

10.5194/bg-8-267-2011 ◽

2011 ◽

Vol 8 (2) ◽

pp. 267-278 ◽

Cited By ~ 36

Author(s):

R. Siano ◽

C. Alves-de-Souza ◽

E. Foulon ◽

El M. Bendif ◽

N. Simon ◽

...

Keyword(s):

Mediterranean Sea ◽

Marine Ecosystems ◽

Natural Environments ◽

Coastal Station ◽

Host Diversity ◽

Eukaryotic Community ◽

Wide Range ◽

The Mediterranean ◽

Host Infection

Abstract. Sequences affiliated to Syndiniales (Marine alveolate, MALV) regularly dominate 18S rDNA genetic libraries of nearly all marine ecosystems investigated so far. Among them, Amoebophryidae (MALV group II) is composed of numerous and genetically distant environmental sequences, where Amoebophrya is the only known and formally described genus. Amoebophrya species include virulent pathogens for a wide range of dinoflagellate species. Beside their regular occurrence in marine ecosystems, their quantitative distribution and the environmental factors triggering host infection have barely been studied in open oligotrophic waters. In order to understand the functional role of these parasites in natural environments, we studied the distribution and contribution to the eukaryotic community of the small free-living stage of Amoebophryidae (the dinospores) along a transect in the Mediterranean Sea, as well as their host diversity at three oligotrophic stations. Dinospores were more abundant at a coastal station (max. 1.5 × 103 cells ml−1) than in oligotrophic waters (max. 51 ± 16.3 cells ml−1), where they represented 10.3 to 34.9% of the total eukaryotic community at 40 and 30 m depth, respectively and 21.2% on average along the water column. Positive correlation was found between dinospore occurrence and higher concentration of NO3 + NO2 at the coastal station. At selected stations, out of 38 different dinoflagellates taxa identified, 15 were infected, among which a majority were not recognized as Amoebophryidae host so far. Prevalences (percentage of infected cells) generally varied between 1% and 10%, with a notable exception for Blepharocysta paulsenii for which 25% of cells were infected at the most oligotrophic station. The present study shows that dinospores are able to thrive and infect dinoflagellates both in coastal and ultra-oligotrophic open waters. Our results emphasize the role of parasitism in microbial food web dynamics and ultimately on biogeochemical cycles.

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Habitat suitability mapping of the black coral Leiopathes glaberrima to support conservation of vulnerable marine ecosystems

Scientific Reports ◽

10.1038/s41598-021-95256-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

V. Lauria ◽

D. Massi ◽

F. Fiorentino ◽

G. Milisenda ◽

T. Cillari

Keyword(s):

Spatial Distribution ◽

Mediterranean Sea ◽

Large Scale ◽

High Sensitivity ◽

Marine Ecosystems ◽

Slope Aspect ◽

Suitable Habitat ◽

Environmental Predictors ◽

Black Coral ◽

The Mediterranean

AbstractThe black coral Leiopathes glaberrima is an important habitat forming species that supports benthic biodiversity. Due to its high sensitivity to fishing activities, it has been classified as indicator of Vulnerable Marine Ecosystems (VMEs). However, the information on its habitat selection and large-scale spatial distribution in the Mediterranean Sea is poor. In this study a thorough literature review on the occurrence of L. glaberrima across the Mediterranean Sea was undertaken. Predictive modelling was carried out to produce the first continuous map of L. glaberrima suitable habitat in the central sector of the Mediterranean Sea. MaxEnt modeling was used to predict L. glaberrima probability of presence as a function of seven environmental predictors (bathymetry, slope, aspect North–South and East–West, kinetic energy due to currents at the seabed, seabed habitat types and sea bottom temperature). Our results show that bathymetry, slope and aspect are the most important factors driving L. glaberrima spatial distribution, while in less extent the other environmental variables. This study adds relevant information on the spatial distribution of vulnerable deep water corals in relation to the environmental factors in the Mediterranean Sea. It provides an important background for marine spatial planning especially for prioritizing areas for the conservation of VMEs.

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“Fuel Burns Mixed with Seawater”: The Relationship between the Refugee Tragedy and the Ecological Crisis in the Mediterranean Sea in Khaled Mattawa’s Mare Nostrum (2019)

Arab World English Journal For Translation and Literary Studies ◽

10.24093/awejtls/vol5no1.15 ◽

2021 ◽

Vol 5 (1) ◽

pp. 210-224

Author(s):

Ashwaq Basnawi

Keyword(s):

Environmental Sustainability ◽

Middle Eastern ◽

Contemporary Literature ◽

Marine Ecosystems ◽

Ecological Crisis ◽

First Century ◽

North African ◽

Political Crises ◽

The Mediterranean ◽

American Poets

With environmental sustainability gaining more attention in contemporary literature, Arab-American poets have begun to focus on the connection between nature and current Middle Eastern and North African politics. Khaled Mattawa’s fifth collection of poems, Mare Nostrum (2019), discusses the twenty-first-century refugee crisis in the Mediterranean through the effects of economics and environmental destruction on both humans and marine ecosystems alike. This paper aims to examine the Mediterranean migrant tragedy’s entanglement with its ecological crisis in Mattawa’s poems. The study seeks to answer the question: can an analysis of Mare Nostrum (2019) illustrate a parallel between humans’ oppression and the environment? A postcolonial ecocritical lens can explore this connection by looking at the “changing relationship between people, animals, and environment . . . that can be recuperated for anticolonial critique” (Huggan and Tiffin 12). The study’s significance exists in showing the destructive impact of political crises that extend beyond human displacement to become an ecological issue that threatens marine ecosystems. The study’s findings reveal that Mattawa’s poems illustrate that the environmental and humanitarian crisis in the Mediterranean is a result of both economic and political instability.

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Extreme event waves in marine ecosystems: an application to Mediterranean Sea surface chlorophyll

Biogeosciences ◽

10.5194/bg-17-5967-2020 ◽

2020 ◽

Vol 17 (23) ◽

pp. 5967-5988

Author(s):

Valeria Di Biagio ◽

Gianpiero Cossarini ◽

Stefano Salon ◽

Cosimo Solidoro

Keyword(s):

Mediterranean Sea ◽

Extreme Events ◽

Extreme Event ◽

Marine Ecosystems ◽

Fuzzy Classification ◽

Ecosystem Functions ◽

Biogeochemical Model ◽

Open Sea ◽

Basin Scale ◽

The Mediterranean

Abstract. We propose a new method to identify and characterise the occurrence of prolonged extreme events in marine ecosystems at the basin scale. There is growing interest in events that can affect ecosystem functions and services in a changing climate. Our method identifies extreme events as the peak occurrences over a predefined threshold (i.e. the 99th percentile) computed from a local time series, and it defines a series of extreme events that are connected over space and time as an extreme event wave (EEW). The main features of EEWs are then characterised by a set of novel indexes, related to initiation, extent, duration and strength. The indexes associated with the areas covered by each EEW were then statistically analysed to highlight the main features of the EEWs in the considered domain. We applied the method to a multidecadal series of winter–spring daily chlorophyll fields that was produced by a validated coupled hydrodynamic–biogeochemical model of the Mediterranean open-sea ecosystem. This application allowed us to identify and characterise surface chlorophyll EEWs in the period from 1994 to 2012. Finally, a fuzzy classification of EEW indexes provided bio-regionalisation of the Mediterranean Sea based on the occurrence of chlorophyll EEWs with different regimes.

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The Mediterranean climate as a template for Mediterranean marine ecosystems: the example of the northeast Spanish littoral

Progress In Oceanography ◽

10.1016/s0079-6611(99)00028-2 ◽

1999 ◽

Vol 44 (1-3) ◽

pp. 245-270 ◽

Cited By ~ 77

Author(s):

Carlos M Duarte ◽

Susana Agustı́ ◽

Hilary Kennedy ◽

Dolors Vaqué

Keyword(s):

Mediterranean Climate ◽

Marine Ecosystems ◽

The Mediterranean

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Phytoplankton Production in Oligotrophic Marine Ecosystems: The Mediterranean Sea

Mediterranean Marine Ecosystems ◽

10.1007/978-1-4899-2248-9_11 ◽

1985 ◽

pp. 231-246 ◽

Cited By ~ 2

Author(s):

Trevor Platt

Keyword(s):

Mediterranean Sea ◽

Marine Ecosystems ◽

Phytoplankton Production ◽

The Mediterranean

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Population genomic structure of the black coral Antipathella subpinnata in Mediterranean Vulnerable Marine Ecosystems

Coral Reefs ◽

10.1007/s00338-021-02078-x ◽

2021 ◽

Author(s):

Marko Terzin ◽

Maria Grazia Paletta ◽

Kenan Matterson ◽

Martina Coppari ◽

Giorgio Bavestrello ◽

...

Keyword(s):

Human Impact ◽

Dna Analysis ◽

Genomic Structure ◽

Marine Ecosystems ◽

Genetic Connectivity ◽

Northwestern Part ◽

Valuable Insight ◽

Black Coral ◽

Black Corals ◽

The Mediterranean

AbstractAntipathella subpinnata(Ellis and Solander 1786) is one of the most frequently observed black corals at mesophotic depths (60–200 m) of the Mediterranean Sea, particularly in the northwestern part of the basin, where its populations can reach high densities and create forest-like aggregations, both along the coast and in offshore locations such as seamounts. Similar to other marine underwater forests, black coral gardens host a rich associated fauna and attract numerous species of commercial interest. As such, these corals are targeted by recreational and artisanal fisheries and are vulnerable to human impact due to their arborescent morphology and low growth rates. Genetic connectivity can provide valuable insight into the processes of population maintenance and replenishment following environmental disturbance and is often used as a proxy for population resilience. In our study, a restriction-site associated DNA analysis (2bRAD) was used to evaluate fine-scale population structure of the Mediterranean black coralA. subpinnata, and to understand which populations could serve as a potential source of genetic diversity for adjacent populations. Colonies from two offshore localities (a Ligurian seamount and a Tyrrhenian canyon) and four coastal populations from Liguria and Sicily were sampled and genotyped. Significant genetic differentiation was recorded between coastal and offshore localities. Moreover, offshore localities were genetically distinct from one another, while all coastal populations were characterized by panmixia. This indicates that offshoreA. subpinnatagardens are potentially less resilient to human impact (i.e., demersal fishing activities) due to a limited influx of larvae from adjacent habitats. In addition, they are unlikely to supply coral propagules to coastal populations. Overall, this study highlights the vulnerability of MediterraneanA. subpinnataforests, and the importance of enforcing conservation and management measures to achieve Good Environmental Status (GES, EU Marine Strategy Framework Directive) of these valuable marine ecosystems.

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