Evina Gontikaki

• Doctor of Philosophy
• Assistant Researcher at Foundation for Research and Technology Hellas

Elucidating marine microbiota diversity and dynamics holds significant importance due to their role in maintaining vital ecosystem functions and services including climate regulation. This work aims to contribute in the understanding of microbial ecology and networking in one of the world’s most understudied marine regions, the Eastern Mediterranea...

Understanding the diversity and dynamics of marine microbiota holds significant importance due to their role in maintaining vital ecosystem functions and services including climate regulation and bioremediation. Here, we studied the diversity and associations between Bacteria and unicellular eukaryotes in the different water masses of the Cretan Pa...

Mesopelagic water from the deep Eastern Mediterranean Sea (EMS) was collected under disrupted (REPRESS) or undisturbed (HP) pressure conditions and was acclimated to oil (OIL) or dispersed-oil (DISPOIL) under in situ pressure and temperature (10 MPa, 14 °C). Decompression resulted in oil-acclimatised microbial communities of lower diversity despite...

To achieve sustainable development, the energy transition from lignite burning to renewable energy resources for electric power generation is essential for Greece. Wind and solar energy have emerged as significant sources in this transition. Surprisingly, numerous studies have examined the potential for onshore wind based on land eligibility, while...

Hydrocarbon biodegradation rates in the deep-sea have been largely determined under atmospheric pressure, which may lead to non-representative results. In this work, we aim to study the response of deep-sea microbial communities of the Eastern Mediterranean Sea (EMS) to oil contamination at in situ environmental conditions and provide representativ...

The diversity and degradation capacity of hydrocarbon-degrading consortia from surface and deep waters of the Eastern Mediterranean Sea were studied in time-series experiments. Microcosms were set up in ONR7a medium at in situ temperatures of 25 °C and 14 °C for the Surface and Deep consortia, respectively, and crude oil as the sole source of carbo...

The occurrence of priming effects (PEs) on the degradation of particulate terrestrial organic matter (OM) (¹³C-wheat detritus) was studied in marine sediments using phytoplankton detritus as priming inducer. Two scenarios, i.e., single-pulse vs. repetitive deposition of same amounts of algal detritus, were tested in sediment core incubation experim...

The Hatton–Rockall Basin (North‐East Atlantic) is an area with potential for deep‐sea (2,900 m) hydrocarbon exploration. Following the Deepwater Horizon oil spill, many investigations into the responses of sediment microbial communities to oil pollution have been undertaken. However, hydrostatic pressure is a parameter that is often omitted due to...

Oil reserves in deep-sea sediments are currently subject to intense exploration, with associated risks of oil spills. Previous research suggests that microbial communities from deep-sea sediment (>1000 m) can degrade hydrocarbons, but have a lower degradation ability than shallow (<200 m) communities, probably due to in situ temperature. This study...

Aims: The aim of this study was the baseline description of oil-degrading sediment bacteria along a depth transect in the Faroe-Shetland Channel (FSC) and the identification of biomarker taxa for the detection of oil contamination in FSC sediments. Methods and results: Oil-degrading sediment bacteria from 135, 500 and 1000 m were enriched in cul...

Deep sea oil exploration is increasing and presents environmental challenges for deep ocean ecosystems. Marine oil spills often result in contamination of sediments with oil; following the Deepwater Horizon (DwH) disaster up to 31% of the released oil entrained in the water column was deposited as oily residues on the seabed. Although the aftermath...

The microbial degradation of petroleum hydrocarbons at low temperatures was investigated in subarctic deep-sea sediments in the Faroe Shetland Channel (FSC). The effect of the marine oil dispersant, Superdispersant 25 on hydrocarbon degradation was also examined. Sediments collected at 500 and 1000 m depth were spiked with a model oil containing 20...

More than 50% of terrestrially-derived organic carbon (terrOC) flux from the continents to the ocean is remineralised in the coastal zone despite its perceived high refractivity. The efficient degradation of terrOC in the marine environment could be fuelled by labile marine-derived material, a phenomenon known as "priming effect", but experimental...

Comparison of the enriched PLFA dataset from this study with published PLFA profiles of known or suspected lignocellulose-degrading bacteria. (DOC)

Hydrothermal fields are habitats with worldwide distribution in the seafloor where chemosynthetic primary producers form the basis of life. In this study, we examined microbial mat communities from volcanic sites within the Hellenic Volcanic Arc (HVA) located in the Aegean Sea. The HVA is a unique site geologically due to the occurrence of volcan...

The priming effect (PE) is a complex phenomenon which describes a modification (acceleration or retardation) in the mineralisation rate of refractory organic matter (OM) following inputs of labile material. PEs are well-studied in terrestrial ecosystems owing to their potential importance in the evolution of soil carbon stocks but have been largely...

Optimal models from the analysis of total mineralisation ( Table 1 ), diatom OM mineralisation ( Table 2 ) and priming effect ( Table 3 ) data for the effect of time (continuous variable), station (categorical variable, levels: St500, St700, St900) and treatment (categorical variable, levels: LC, MC, HC). (DOCX)

Spatial distribution and patchiness of deep sea macrofaunal communities were studied from samples collected in the Rockall Trough, NE Atlantic. In June 2011, two areas, located outside and within the Darwin Mound Special Area of Conservation (SAC), were sampled. Three megacores were deployed in each area at approximately 900 m depth. The two areas,...

Continental margin sediments (<2000 m) cover merely 15 % of the ocean's seafloor but are responsible for more than 70 % of the global benthic mineralization. Understanding when these systems act as a source or sink of carbon (C) is thus of primary importance if we are to produce reliable global C budgets and predict the effects of future perturbati...

Over the past two decades, growing concerns have been raised regarding the effects of towed fishing gears, such as trawls and dredges, on deep-sea biodiversity and ecosystem functioning. Trawling disturbs the benthic communities both physically and biologically, and can eliminate the most vulnerable organisms and modify habitat structure; chronical...

Abstract The response of a deep-water benthic microbial community to organic matter (OM) enrichment was studied in the unexplored region of the SW Cretan margin (E. Mediterranean). A food pulse of 0.5 g C m?2 was simulated by adding 13C-labelled diatoms to sediment cores retrieved from 1079 m depth. The diatom addition resulted in a significant inc...

The benthic food web of the deep Faroe–Shetland Channel (FSC) was modelled by using the linear inverse modelling methodology. The reconstruction of carbon pathways by inverse analysis was based on benthic oxygen uptake rates, biomass data and transfer of labile carbon through the food web as revealed by a pulse-chase experiment. Carbon deposition w...

The response of a sub-arctic, deep-sea macrofaunal community to a simulated food sedimentation event was studied by means of a stable isotope ‘‘pulse-chase’’ experiment. A food pulse was simulated by adding 500 mg Cm-2 of 13C-labelled diatoms, Chaetoceros radicans, to sediment cores retrieved from 1080m in the Faroe-Shetland Channel. Carbon uptake...

The carbon (C) budget in bathyal permanently cold sediments was assessed by means of a pulse-chase experiment in the deep Faroe-Shetland Channel (FSC). The food pulse was simulated by adding 500 mg C m(-2) of the C-13-labelled marine diatom Chaetoceros radicans to sediment cores retrieved from 1080 m in the FSC. The fate of the tracer was followed...

Two species of bivalves, Cerastoderma glaucum and Abra ovata, typical inhabitants of brackish waters, were found in Vouliagmeni Lagoon. Seasonal qualitative and quantitative samples were extracted from the different types of the substratum during 1997–1998. Overall, 800 individuals of C. glaucum and 2700 individuals of A. ovata were collected and m...