The main outputs of a multidisciplinary and integrated studies are summarised. The results incorporate the latest biogeochemical researches, at basin scale, in the Aegean Sea (including thermohaline circulation studies, SPM dynamics, mass and energy fluxes, acknowledge biochemical processes in the euphotic and the benthic layer and benthic response to downward fluxes). The data were acquired within five (seasonal) research cruises, during 1997-1998. Data analysis and evaluation hence provided important new information on the functional processes of the Aegean ecosystem. In terms of water circulation, no new deep water formation in the Aegean Sea was observed, during 1997-1998, but rather intermediate water, due mainly to the mild winter conditions. All the biochemical parameters of the euphotic zone (nutrients, Particulate Organic Carbon (POC), chlorophyll-a, phytoplankton, primary and bacterial production), although high in the N. Aegean Sea reflect clearly the highly oligotrophic character of the Aegean Sea. In the N. Aegean, microbial food web was the main pathway of carbon, whereas in the S. Aegean, the food web could be classified as multivorous. An important Black Sea Water (BSW) signal was observed in the dissolved phase; this was especially pronounced in the Dissolved Organic Carbon (DOC), Mn and to a lesser degree to Cd, Cu and Ni concentrations. The downward material fluxes are higher in the N. Aegean, relative to the S. Aegean. Substantially higher values of near-bottom mass fluxes were measured in the deep basins of the N. Aegean, implying significant deep lateral fluxes of POM. The N. Aegean could be classified as a ''continental margin'' ecosystem, whilst the S. Aegean is a typical ''oceanic margin'' environment. There is a close relationship and, consequently, coupling between the near-bottom mass fluxes and the accumulation rates of organic matter (OM), with the near-bottom mineralisation, bioturbation, redox potential, oxygen consumption rates, the sediment microbiological and enzymatic activity and the meio-macro-and mega fauna abundances in the

[1] The modern Aegean Sea is an important source of deep water for the eastern Mediterranean. Its contribution to deep water ventilation is known to fluctuate in response to climatic variation on a decadal timescale. This study uses marine micropalaeontological and stable isotope data to investigate longer-term variability during the late glacial and Holocene, in particular that associated with the deposition of the early Holocene dysoxic/anoxic sapropel S1. Concentrating on the onset of sapropel-forming conditions, we identify the start of ''seasonal'' stratification and highlight a lag in d18 O response of the planktonic foraminifer N. pachyderma to termination T1b as identified in the d18 O record of G. ruber. By use of a simple model we determine that this offset cannot be a function of bioturbation effects. The lag is of the order of 1 kyr and suggests that isolation of intermediate/deep water preceded the start of sapropel formation by up to 1.5 kyr. Using this discovery, we propose an explanation for the major unresolved problem in sapropel studies, namely, the source of nutrient supply required for export productivity to reach levels needed for sustained sapropel deposition. We suggest that nutrients had been accumulating in a stagnant basin for 1 -1.5 kyr and that these accumulated resources were utilized during the deposition of S1. In addition, we provide a first quantitative estimate of the diffusive (1/e) mixing timescale for the eastern Mediterranean in its ''stratified'' sapropel mode, which is of the order of 450 years.

Long-piston coring in the central Gulf of Corinth Basin was performed in 2001 on board the RSS Marion Dufresne, enabling the recovery of lacustrine sediments buried at 12-13.5 mbsf below Holocene marine sediments. The lacustrine sequence consists of varve-like muddy, organically rich, layers interbedded with silty and fine sand turbidites. AMS dating determined the age of the marine-lacustrine interface at 13 kyr BP. Vertical fault slip rates were measured by using fault offsets of correlated reflectors. The maximum subsidence rate of the depocentre (3.6 mm yr −1 ) exceeds the maximum sedimentation rate by 1.8 mm yr −1 , which, consequently, corresponds to the rate of deepening of the basin floor. Data on the water level during the last glacial period indicate that the Corinth-Lake level was about 80 m lower than the present sea level. Inflow of seawater through the Rio-Antirio sill, as a consequence of the last eustatic sea level rise, may have caused catastrophic marine flooding phenomena in the Gulf of Corinth, similar to the one reported from the Black Sea.

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