Habitat (β) diversity in upper infralittoral rocky shores on the southern coast of Turkey

Increasing threats to biodiversity and habitats, are increasing the importance of understanding and exploring the different components of biodiversity, such as habitat (beta) diversity. In this study, the beta diversity of macrozoobenthic communities sampled, as a part of TUBITAK project coded 104Y065, from different habitats in the rocky upper infralittoral zone on the Mediterranean coasts of Turkey and determinants and factors effecting the beta diversity were investigated. Comparing the alpha and beta diversity of different habitats, determining the beta diversity of subregions and the determinants and factors effect it, and determining the effect of alien species on beta diversity constitues the aim of this thesis. Although mussel and sponge habitats contain fewer species on average in comparison to macroalgae habitats, they had higher average beta index. In similarity analysis, macroalgae habitats were more similar to each other, while mussel and sponge habitats show less similarity with this group. As a result of BEST analysis, indicating correlation between physicochemical parameters and community structure, stations were divided into two main regions. The correlation between the physicochemical parameters and the community structure was high in the eastern stations while it was very low in the western stations. In addition, the average number of species in the eastern stations was low, but the beta diversity was high, whereas it was the opposite in the western stations. The same case was also valid for species number and beta diversity of alien species. There was a decrease in beta diversity with the inclusion of alien species. The findings obtained within the scope of the thesis reveals that an approach considering the different ecosystems as defined on the basis of physicochemical parameters and the spatial and temporal characteristics of different habitats within these ecosystems, is an important tool to determine and evaluate the species diversity of the Mediterranean coasts, the contribution of different habitat types to biodiversity and the impact of alien species since it can provide more and examinable findings and information.