Implementation of a new Non-destructive Phytobenthic Index (NPI) with the Posidonia Biotic Index (BiPo) to evaluate the ecological status of the Turkish Aegean coasts (Eastern Mediterranean)

Within this study, the ecosystem status of the Aegean Sea coasts of Türkiye (Eastern Mediterranean) was assessed using the Posidonia Biotic Index (BiPo) and a newly proposed Non-destructive Phytobenthic Index (NPI) according to the requirements of the Water Framework Directive (WFD 2000/60/EC). In addition, their relations with Land Uses Simplified Index for shallow water macroalgae (MA₋LUSI) were evaluated. The descriptors measured through NPI were: shoot density, cover, depth and type of lower limit of Posidonia meadows and cover of other macrophytic communities; Cymodocea/Zostera, canopy forming brown, coralligenous, opportunistic and alien macroalgae. The “good” status is presented by mean value of the BiPo (0.69) at 20 sites, while “moderate” status is presented by NPI (0.59) at 25 sites. Simultaneous implementation of the biotic indices proved their consistency (r=0.745), while negative relations between MA-LUSI and the BiPo (r=-0.243) and NPI (r=-0.450), underlined their capability to assess the degradation of macrophytic communities in anthropized regions.