Organic matter characterization and copper complexing capacity in the sea surface microlayer of coastal areas of the Eastern Mediterranean

While the enrichment factor (EF) of a compound is defined as the ratio of the concentration in the SML to that in the corresponding underlying water, the mean EF values of dissolved surface active substances (SASd: 5.8 ± 5.8) and transparent exopolymer particles (TEPcolor: 2.2 ± 1.8, TEPmicro: 3.8 ± 5.6) were significantly greater than unity (p = 0.0121, 0.0220 and 0.0404 respectively) indicating a general enrichment of these organic materials in SML. SASs, normalized to DOC concentrations, have shown that the organic matter pool studied was mostly hydrophilic. During winter (February 2013) an enrichment of LT in SML was detected at all of the sampling sites examined, paralleled by TEP aggregation suggesting a role for TEP in copper complexation.