Supervisors info:
Ευάγγελος Μπακέας, Αναπληρωτής Καθηγητής ΕΚΠΑ
Εμμανουήλ Δασενάκης, Καθηγητής ΕΚΠΑ
Χαράλαμπος Προεστός, Επίκουρος Καθηγητής ΕΚΠΑ
Summary:
The marine surface microlayer (SML) represents the ocean boundary between the ocean and the atmosphere, with a typical thickness of 30 to 300 μm. The SML is known to exist even at higher than global average wind speeds, covering most of the ocean's surface and it is therefore of global biogeochemical significance. In the first 50 μm, over 20 properties such as the concentration of suspended particles, density, pH, chemical and biological composition, complexity and other parameters change sharply. These unique features help to increase the interfacial effect of the marine surface microlayer, which has a unique chemical composition and where numerous processes occur.
The present study investigates the complexing capacity of cadmium, copper and zinc ions in the SML, compared to the underlying water layer (ULW) and to water obtained nearby the sea bottom (B) in seawater samples originating from the coastal stations of Loutropyrgos and Pachi located within the Elefsis and Saronicos gulfs, respectively, by applying the method of Differential Pulse Anodic Stripping Voltammetry (DPASV), using the Hanging Mercury Drop Electrode (HMDE).
The copper complexing capacity was determined to range from 29 to 201 nM for SML samples, for the samples of underlying layer from 22 to 136 nM and for deeper samples from 25 to 115 nM.
The cadmium complexing capacity was determined to range from 0.9 to 2.7 nM for SML samples, for the samples of underlying layer from 0.9 to 3.1 nM, while for deeper samples from 0.3 to 4 nM.
Finally, the zinc complexing capacity was determined to range from 2.1 to 53 nM for SML samples, for the samples of underlying layer from 29 to 79 nM, and for deeper samples from 29 to 136 nM.
The determined values for copper complexing capacity are comparable to the few data published so far in international literature, whereas for the cases of cadmium and zinc no relevant data are available.
Keywords:
marine surface microlayer, complexing capacity of cadmium, copper, zinc