Evangelia Krasakopoulou

University of the Aegean · Department of Marine Sciences

Shipping is responsible for a range of different pressures affecting air quality, climate, and the marine environment. Most social and economic analyses of shipping have focused on air pollution assessment and how shipping may impact climate change and human health. This risks that policies may be biased towards air pollution and climate change, wh...

Purpose The objective of this work is to study environmental changes and contamination during the last century in a semi-closed marine system, by performing measurements on the sediment which is the final recipient of discharged matter. Methods Sediment cores were sampled with a box-corer and were analyzed using gamma-ray spectrometry for activity...

My Blue Home is an Erasmus+ project, undertaken by a partnership of six organizations in the wider education realm. The project aims to expand ocean literacy among school children aged six to ten years old by employing an innovative dual approach: creating a Digital Ocean Game which will be freely available online, to be employed in schools worldwi...

Water quality modeling is a key element for the support of environmental protection and policymaking. The aim of this work is to describe the application of a far-field water quality model for the simulation of marine pollution occurring from heavy metals (cadmium, lead, nickel, copper, and zinc). The highly stressed marine area of the Saronikos Gu...

The Thermaikos Gulf (TG) is a semi-enclosed, river-influenced, marine system situated in the eastern Mediterranean Sea, sustaining both urban coastal regions and ecologically preserved natural areas. Facing a plethora of environmental and anthropogenic pressures, the TG serves as a critical nexus where human activities intersect with marine ecosyst...

Thermaikos Gulf (TG) is a semi-enclosed, river-influenced, marine system situated in the eastern Mediterranean Sea, sustaining both urban coastal regions and ecologically preserved natural areas. Facing a plethora of environmental and anthropogenic pressures, the TG serves as a critical nexus where human activities intersect with marine ecosystems....

Plastic additives include a wide range of pollutants, added throughout the production process of plastics aiming to improve their properties. Given that they are not chemically bound to the plastic items, they can easily migrate in the marine environment allowing their uptake by marine organisms and accumulation in their tissues. Representatives of...

The rate of ocean uptake of anthropogenic CO2 has declined over the past decade, so a critical question for science and policy is whether the ocean will continue to act as a sink. Large areas of the ocean remain without observations for carbonate system variables, and oceanic CO2 observations have declined since 2017. The Mediterranean Sea is one s...

The Mediterranean Sea has been sampled irregularly by research vessels in the past, mostly by national expeditions in regional waters. To monitor the hydrographic, biogeochemical and circulation changes in the Mediterranean Sea, a systematic repeat oceanographic survey programme called Med-SHIP was recommended by the Mediterranean Science Commissio...

This work offers an overview description of the natural environment and anthropogenic pressures in the Thermaikos Gulf along the land-sea continuum, encompassing coastal areas and hinterlands, shaped by major rivers and diverse geological formations. Coastal zones experience anthropogenic pressures from urbanization, industry, agriculture, and tour...

Endocrine disruptors include a wide range of pollutants that can affect the endocrine system of the organism and cause abnormalities in hormone-regulated functions (e.g., growth, reproduction, and metabolism). Plastic additives, such as phthalates and bisphenol A (BPA), and trace elements have been identified as endocrine disruptors and pose a majo...

Over the past few decades, the scientific community has extensively investigated microplastics (MPs) and their interactions with marine organisms. MPs ingestion has been one of the most commonly examined topics across marine fauna. In this study, we present a systematic review conducted to gather information on the MPs ingestion by different taxono...

The aim of this study is to investigate the distribution of selected Polycyclic Aromatic Hydrocarbons (PAHs) and predict their fate in the marine area of Saronikos Gulf. A three-dimensional model (Delft3D-FLOW) was used to simulate sea circulation and hydrographic variables (salinity, temperature), for a 365-day simulation time period (year 2018)....

The aim of this study is to investigate the distribution of selected Polycyclic Aromatic Hydrocarbons (PAHs) and predict their fate in the marine area of Saronikos Gulf. A three-dimensional model (Delft3D-FLOW) was used to simulate sea circulation and hydrographic variables (salinity, temperature), for a 365-day simulation time period (year 2018)....

In the period 1987-2017, a series of physical and chemical measurements related to oxygen variability at a trough area with a maximum depth of ~420 m in the West Saronikos Gulf, reveal the following: In the early 90s, deep winter mixing occurred resulting in an oxygenation down to ~420 m followed by an oxygen decline. This decline reached near-bott...

The coastal marine ecosystem of Saronikos Gulf, a busy Eastern Mediterranean embayment directly impacted by the greater metropolitan area of Greece's capital, Athens, is examined through a series of state-of-the-art numerical models that address the hydrodynamics (Delft3D-FLOW), the wave regime (SWAN), the biogeochemistry, and pollution related to...

The North Aegean Sea is a sub-basin of the Mediterranean which exhibits a range of oceanic processes at various scales. Due to the inflow of very light, mesotrophic Black-Sea waters it is the most productive region of the seas around the Hellenic Peninsula, although the regular seasonal coastal upwelling along its eastern shores does not contribute...

Climate change driven by human activities encompasses the increase in atmospheric CO2 concentration and sea-surface temperature. Little is known regarding the synergistic effects of these phenomena on bacterial communities in oligotrophic marine ecosystems that are expected to be particularly vulnerable. Here, we studied bacterial community composi...

We present a new concept for marine research, applied in the EU-funded project EMERGE, “Evaluation, control and Mitigation of the EnviRonmental impacts of shippinG Emissions” (2020–2024; https://emerge-h2020.eu/). For the first time, both the various marine and atmospheric impacts of the shipping sector have been and will be comprehensively analyze...

Recent spatial and vertical distributions of 137Cs activity concentration in the Aegean Sea are presented almost 30 years after the Chernobyl accident. The study aims to provide the current radioactivity levels of 137Cs in the Aegean Sea and to combine the 137Cs activity concentration with typical oceanographic parameters (T, S) in order to utilize...

The Saronikos Gulf and the small emBayment of Elefsis Bay (Eastern Mediterranean, Greece) represent the seaward boundary of the metropolitan areas of Athens and Piraeus Port, hosting 1/3 of the current Greek population. It constitutes a complex ecosystem due to the topographical and hydrological differentiation of the area, as well as its trophic c...

Ocean acidification (OA) is a serious consequence of climate change with complex organism-to-ecosystem effects that have been observed through field observations but are mainly derived from experimental studies. Although OA trends and the resulting biological impacts are likely exacerbated in the semi-enclosed and highly populated Mediterranean Sea...

The first and most significant elements of a Coastal Environmental Observatory for the North Aegean Sea have been installed, focusing mostly on the semi-enclosed basin of Kalloni Bay, Lesvos, Greece. The Observatory aims to support both research and educational activities, as well as provide environmental information services to stakeholders rangin...

In the framework of the European Project "Evaluation, control and mitigation of the environmental impacts of shipping emissions (EMERGE)", a wide spectrum of Greek scientists from several disciplines ranging from atmospheric sciences to marine biology have joined forces in order to assess the impact of the widespread adoption of marine scrubbers by...

The last decade increasing attention to litter accumulation in the marine environment revealed the issue of the terrestrial fluxes of plastic pollution into the oceans. However, limited studies investigate the macro-litter abundance and composition particularly in freshwater ecosystems and the adjusted coastal environment. In this study, we conduct...

The major natural factors of the South Evvoikos Gulf are the existence of an almost closed boundary and the increase of the gulf width moving to the other boundary of the gulf; the later favors the communication with the South Aegean Sea and the entrance of the relevant water mass. In their turn, abiotic (salinity, nutrients, particulate carbon, se...

The concentrations and distribution of nutrients and carbon in the Aegean Sea are strongly influenced by the biogeochemical processes, the complex hydrological and circulation characteristics, as well as by the geographic setting and bottom topography of its sub-basins. Historical data have shown that the distribution of oxygen and nutrients in the...

The Eastern Mediterranean Transient (EMT) was a major climatic event, as it affected profoundly and for a long time period, the circulation of the deep and intermediate layers, with important consequences on the distribution of oxygen and nutrients in the Ionian Sea and more generally, in the whole Eastern Mediterranean basin. In this paper, nutrie...

Rising scientific literature and legislation measures have highlighted the concern on plastic pollution and the issue of microplastics. In the context of this study, 3 marine species of commercial interest (bogues, Mediterranean mussels, blue crabs) were examined, concerning microplastics’ presence and characteristics. The abundance of the ingested...

The focus of the presentation was to report microplastic ingestion in marine species of commercial, North Aegean Sea

Marine litter monitoring: the case study of Paros Island

Marine litter have been characterized as one of the main threats for societies, while among them, plastics have been found in various marine ecosystems. A monitoring project on marine litter, based on beach visual-surveys started in 2019, on Paros Island in the Aegean Sea, under the Clean Blue Paros initiative. Four main sandy beaches with differen...

A medium resolution underwater gamma ray spectrometer was deployed in the submarine groundwater spring of Anavalos and was combined with conductivity and temperature sensors for continuous measurements of natural radioactivity, salinity and water temperature, respectively. The activity concentrations of radon progenies varied from (5–40) kBq m⁻³, e...

Metal and metallothionein (MT) in mixed zooplankton were investigated as means of monitoring metal availability regarding environmental exposure. Spatial and temporal variability of Cd, Cu, Ni, Zn, Fe, Mn and Pb in zooplankton and seawater were studied in Saronikos Gulf (Aegean Sea, Eastern Mediterranean), once every second month during an annual c...

A review of the evolution of ¹³⁷Cs activity concentrations in the Aegean Sea is presented almost 34 years after the Chernobyl accident. The data from field measurements are interpreted considering the different water masses present in the Aegean Sea, for better understanding of ¹³⁷Cs spatial and temporal variation. The last 15 years, a lot of effor...

Mesocosm experiments have been fundamental to investigate the effects of elevated CO2 and ocean acidification (OA) on planktic communities. However, few of these experiments have been conducted using naturally nutrient-limited waters and/or considering the combined effects of OA and ocean warming (OW). Coccolithophores are a group of calcifying phy...

Normally atmospheric CO2 is the major driver of ocean acidification (OA); however, local discharge/degradation of organic matter (OM) and redox reactions can exacerbate OA in coastal areas. In this work we study the response of nutrient and carbon systems to pH decrease in relation to hydrographically induced intermittent characteristics and examin...

This study attempts to elucidate the dynamics of phytoplankton biomass (as Chl-a), productivity, community structure and bloom formation in different regions of the oligotrophic Eastern Mediterranean (EMed). With this scope, several chemical and phytoplankton parameters were studied along a transect of 1300 km across different pelagic environments...

Pharmaceuticals and related compounds are increasingly being released into the marine environment, posing health risks to living organisms. Their accurate determination in marine samples is still an analytical challenge, while they can undergo a series of transformation processes resulting in largely unknown transformation products and health effec...

In recent years, the Mediterranean Sea has become an accumulation zone for waste generated by the 22 countries bordering its shores. Although the effects of plastic litter on the marine environment and on organisms have recently been studied in other areas, further information is needed for the Mediterranean Sea and, in particular, about plastics a...

Caesium-137 activity concentrations (¹³⁷Cs) were measured between 2003 and 2014 in the water column of Lemnos and Cretan deep basins of the Aegean Sea. The purpose was to assess water-mass dynamics and mixing processes by combining typical oceanographic data with the activity concentrations of ¹³⁷Cs. The radiological data, combined with dissolved o...

137Cs activity concentration in seawater is an efficient radio-tracing technique to separate and identify the origin of different water masses along with depth. This technique has been applied for the study of deep basins at the North Aegean Sea [1], a marine region which is continuously enriched with 137Cs originated from the Black Sea, through th...

The present study presents a transdisciplinary effort in searching, selecting, developing and implementing indicators for the assessment of ecosystem services (ESs) in the coastal zone. Despite the various classifications developed in recent years, the majority of the relevant studies result in qualitative evaluations of the main ESs of the coastal...

The Mediterranean Sea has a dynamic role in the sequestration of the atmospheric CO2 due to its active overturning circulation and the inherent properties of its waters. The bibliographic review of the CO2-carbonate system properties in the water column of the Mediterranean Sea revealed that the study of the spatial and temporal variability of carb...

There is a general scarcity of oceanic observations that concurrently examine air–sea interactions, coastal–open-ocean processes and physical–biogeochemical processes, in appropriate spatiotemporal scales and under continuous, long-term data acquisition schemes. In the Mediterranean Sea, the resulting knowledge gaps and observing challenges increas...

Microplastics (MPs) in the marine environment have received increased attention over the last few years. A research was conducted in three different locations at Mytilene strait in which floating plastic debris were collected with a Manta net. The samples were analysed and the distribution, the size, the abundance and the shape of MPs was determine...

A natural pH gradient caused by marine CO2 seeps off the Methana peninsula (Saronikos Gulf, eastern Peloponnese peninsula) was used as a natural laboratory to assess potential effects of ocean acidification on coccolithophores. Coccolithophore communities were therefore investigated in plankton samples collected during September 2011, September 201...

Coccolithophore absolute abundances (10 3 cells l-1) and relative abundances (%) at the investigated samples. (XLSX)

Coccolithophore species identified in this study. (XLSX)

Naturally occurring microbial decomposition of organic matter (OM) in coastal marine environments cause increased acidity in deeper layers similar or even exceeding the future predictions for global ocean acidification (OA). Experimental studies in coastal areas characterized by increased inputs of OM and nutrients, coping with intermittent hypoxic...

Aim of this study was to evaluate the abundance and composition of surface beach litter on three beaches of Mytilene (ΜΥΤ1: Kantina 1, ΜΥΤ2: Kochilia, ΜΥΤ3: Kalamari) which during summer are used for recreation. Beach litter collected by hand on November and December, 2015 and February 2016, were classified into seven categories according to its co...

The North Aegean Sea is considered as a region of deep water formation in the Mediterranean. Dense water formation events are known to take place rather infrequently and in the time intervals between such events, the bottom waters are excluded from interaction with other water masses through advection. Successive CTD profiles of an ARGO float trapp...

There is a general scarcity of oceanic observations that concurrently examine air–sea interactions, coastal-open ocean processes, and biogeochemical (BGC) parameters, in appropriate spatiotemporal scales, and under continuous, long-term data acquisition schemes. In the Mediterranean Sea, the resulting knowledge gaps and observing challenges increas...

The Samaria and Lithinon canyons at the southern Cretan margin (Eastern Mediterranean) were studied with respect to hydrography, deep currents, particle dynamics and settling fluxes by utilizing: (a) current-meter and sediment trap records from May 2005 to May 2006; and (b) hydrographic and optical measurements along with particulate matter and par...

The distribution and the chemical composition of Suspended Particulate Matter (SPM), in the northern Thermaikos Gulf, were studied during an annual experiment, carried out from June 2004 to June 2005. Water samples were collected at three depths (1 m below surface, 10 m depth, and 2 m above bottom) and filtered to obtain SPM, particulate organic ca...

Data of AT (total alkalinity) and CT (total inorganic carbon) collected during October 2013, on a N-S transect crossing the North of Lemnos basin allowed to identify the peculiarities of the CO2 system in the North Aegean Sea and estimate the anthropogenic CO2 (CANT) concentrations.

The abundance of Transparent Exopolymer Particles (TEP) was determined on a seasonal basis (autumn, spring and summer) along a north-south transect in the NE Aegean Sea and the vicinity of the Dardanelles Straits. Their distribution patterns were studied in respect to hydrographic conditions and water mass characteristics in the area, as well as pa...

The NE Aegean Sea constitutes a challenging sector of the world ocean in studying optical and biogeochemical properties and processes due to a dynamic frontal regime resulting from the continuous mixing of Black Sea waters (BSW) and waters of Levantine origin (LW), which are characterized by substantially different physical, chemical and biological...

In this work, the hydrodynamic picture of the South Aegean Sea is examined through an analysis of recent measurements in its sub-basins, the Myrtoan and Cretan Sea. Both sub-basins play an important role in the water circulation, exchange, and formation processes that affect the dynamics of the whole Eastern Mediterranean. For the first time, Bio-A...

The Surface Ocean CO2 Atlas (SOCAT) is a synthesis of quality-controlled fCO2 (fugacity of carbon dioxide) values for the global surface oceans and coastal seas with regular updates. Version 3 of SOCAT has 14.7 million fCO2 values from 3646 data sets covering the years 1957 to 2014. This latest version has an additional 4.6 million fCO2 values rela...

In order to identify how ocean acidification will influence biological interactions and fluxes among planktonic organisms and across trophic levels, a large-scale mesocosm experiment was performed in the oligotrophic Northwestern Mediterranean Sea in the framework of the European MedSeA project. Nine mesocosms were deployed in the Bay of Calvi (Cor...