Human impacts can change marine ecosystem bothdirectly and indirectly causing, in the first case, overexploitation and lossof habitat, while, in the latter ones, changes in interactions in the food weband in the structure of environment (Goulletquer et al. 2014). Coastal areasare particularly subject to human pressure, since in this zone are located mostof the anthropogenic activities. Human pressure can modify the natural statusof of physical, chemical, and biological components that characterize marineecosystem (Reiss et al.
2014). Regular monitoring of sediment quality is animportant pursuant to assessing the possible influence of anthropogenicpressure on ecosystem quality (Romeo et al. 2015) and give information tosupport management in order to reach a Good Environmental Status (GES) in the MarineStrategy Framework Directive (MSDF) perspective. Moreover, as reported bynumerous studies (Cozar et al. 2014; Nuelle et al.
2014), the analysis ofmarine sediments is important in the evaluation of the emerging pollutantssuch as microplastics, that tend to accumulate in the sea-bottom. At present, microplasticsrepresent a major global concern affecting all world oceans, defined in theMSFD as D10 into different categories including the plastic debris. Thismaterial, in the environment is subject to a combination of physical,biological and chemical processes that reduce its structural integrity (Cole etal. 2011) producing high densities of smaller debris as microplastics (1-5 mm).
As reported in the Guidance on Monitoring of Marin Litter in European Saes(2013) the monitoring of litter in seafloor cannot consider all coastal areasbecause of limited resources, for this reason also opportunistic approach (i.e. data from other research activityin the harbour) could be used to improve the existing monitoring plans. Recentstudies testify that microplastic can became a threat of biodiversity, becominga vector for the introduction of non-native marine species to new habitats onfloating (Barnes 2002; Derraik 2002; Winston 1982).
In addition, because oftheir size, microplastics are considered bioavailable to organisms throughoutthe food web (Thompson et al. 2004). When ingested, plastics release chemicals compound(nonylphenols, polybrominated diphenyl ethers, phthalates and bisphenol A)together with adsorbed hydrophobic pollutants (i.e. PCBs, TBT, DBT, MBT). Even if, the use of these pollutants wasbounded, their extensive use in the past and their low water solubility makethem persistent and able to accumulate both in sediments and in biota (Harrisand Wiberg 2002) and are measured at significantlevels in marine ecosystems and marine food webs (D’Alessandro et al. 2016).
The sea-floor integrity (D6, MSFD) reflectscharacteristics of the sea bottom influencing, in particular, the structure andfunctioning of communities living on the sea floor (benthic ecosystems). Disturbanceof the bottom may change structure of benthos community damaging mainly sensiblespecies causing biodiversity loss. Macroinvertebrates, due to their skill to modifytheir community patterns in relation to natural and anthropogenic stress(Warwick1988) , are considered great biondicators of marine ecosystem (Warwick 1993;Romeo et al. 2015). Actually, a lot of benthic indices based on structure of macrofaunalcommunities were created to assess the ecological quality status (EcoQ) tosupport data for MSFD, e.g. AMBI (Borjaet al.
2000), M-AMBI (Muxika et al. 2007), BENTIX (Simboura and Zenetos 2002), BOPA(Dauvin and Ruellet 2007). These indices, based on the subdivision of speciesin different ecological groups, return a value of environmentalquality/disturbance status.The aim of this paperis to carry out a quality assessment of a high polluted harbour of the Ionian sub-regionand Central Mediterranean Sea through a multidisciplinary approach thatintegrate biotic and abiotic parameters, in order to give data to improve themonitoring plan of the MSFD regarding shallow waters.