Ecological quality status of the Turkish coastal waters by using marine macrophytes (macroalgae and angiosperms)

•The EEI-c Index was tested to assess the impact in Turkish marine waters.•Pressures by using MA-LUSI index was tested along the Turkish coastline.•A negative linear relationship was found between MA-LUSI and EEI-c.•This study supports the use of the EEI-c index in Turkish coastal waters. Marine macrophytes (macroalgae and angiosperms) were defined as one of the biological quality elements to assess the ecological quality status of transitional and coastal waters by the European Water Framework Directive (WFD, 2000/60/EC). In the present study, the Ecological Evaluation Index (EEI-c) was tested to assess the anthropogenic impact by using marine benthic macrophytes (macroalgae and angiosperms) and pressures by using MA-LUSI in the Turkish marine waters. Macrophyte samples were collected from 56 stations on the coasts of Turkey (at 17 Black Sea, 15 Marmara Sea, 13 Aegean Sea and 11 Mediterranean coastal water bodies) in the summer period between 2014 and 2016. In total, 209 marine macrophytes (macroalgae and angiosperms) taxa were found in all stations. The study revealed high ecological status class for 15 sites, good for 21 sites, moderate for 6 sites, poor for 10 sites, and bad for 4 sites. The MA-LUSI index was tested from the Corine land cover map which affects 1.5 km buffer zone around the sampling sites. The relationship between the pressure index MA-LUSI and EEI-ceqr (eqr: ecological quality ratio) was also tested, and a negative linear relationship was found between MA-LUSI and EEI-ceqr in the Turkish sites. The present study supports the use of the EEI-c index for ecological quality state classification in a wide area of Turkish coastal waters.