Abstract

 https://www.tandfonline.com/doi/abs/10.1080/02757541003705484

An update of the spatial distribution and bio-ecological features of Posidonia oceanica (L.) Delile meadows spread along the coasts of the southern Adriatic and northern Ionian Seas (Apulia region, southern Italy) is reported. Mapping carried out in 2004 indicated a remarkable reduction in the spatial distribution of P. oceanica meadows in the southern Adriatic Sea, mostly northwards of Bari, when compared with 1991 data. By contrast, in the northern Ionian Sea, the spatial distribution seems to be more stable. The P. oceanica meadows covered ?330 km2 distributed along a total of 320 linear km coastline, mostly on the southern side of Apulia. Within natural variability, the differences in bio-ecological features could be due mainly to the presence of anthropic disturbance (urban, industrial and tourist pressure) rather than a significant geographical gradient between the Adriatic and Ionian Seas. However, the mean density values recorded in almost all the Adriatic stations fall within the ‘lower sub-normal density’ (LSD) range. By contrast, the mean density values observed in the Ionian meadows were generally within the ‘normal density’ (ND) range.