Meiofaunal communities in four Adriatic ports: Baseline data for risk assessment in ballast water management.

Ports receive a variety of contaminants related to a wide range of anthropogenic activities - including ship ballast water (BW) - that ultimately find their way to sediments. Benthic meiofauna from four Adriatic ports (Ancona, Trieste, Koper, and Split) was assessed for the main environmental pollutants, to evaluate the effects of human activities on meiobenthos and identify the most appropriate descriptor to assess the ecological quality of marine ecosystems. Sediment analysis demonstrated that Trieste and Split were the most contaminated ports, followed by Koper and Ancona. All meiofaunal parameters showed high spatial and temporal variability, in line with the marked heterogeneity of the four ports. Sand, total organic carbon, and pollutants seemed to be the variables that best explained meiofaunal patterns. Community structure and rare taxa were the meiofaunal descriptors that reflected the environmental status and biological response most accurately. The present data suggest that meiofauna can be used to assess the biological impact of BW.