The biological breakdown processes of the OM in the flocs have received little attention in shallow tidal systems. TEP is readily colonized by bacteria. As a seemingly logical result, bacterial abundances are positively related with TEP. Yet, recent studies question this relationship, as it was shown that bacterial TEP formation may exceed their carbon utilization, thus increasing the amount of refractory TEP. Likewise, it is known that mesozooplankton feeds on detrital POM, but it is not clear to which extent this feeding affects TEP. Prieto et al. (2001) found that copepods do not remove TEP but may influence their size distribution. By contrast, Pedrotti et al. (2010) found that zooplankton grazing affects both the concentration and size distribution of TEP, while Toullec et al. (2019) have shown that copepods may actually increase TEP production. Soo this PhD will investigate if bacterial mineralization and zooplankton grazing have a profound impact on particle degradation and their dynamics.