Evaluation of ecological status of the Persian Gulf inshore waters (Hormozgan rocky bottoms) using macrophytic communities and a macroalgae biological index, EEI

Abstract

Marine benthic macrophytes (seaweed and seagrasses) are key structural and functional components of some of the most productive ecosystems of the world. They absorb nutrients through their surface directly from the marine environment and thus they are very important biological elements for the estimation of ecological status, representing reliable indicators of coastal waters. The aim of this study was to assess the ecological status and trophic level of Hormozgan rocky bottoms according to Ecological Evaluation Index (EEI) .Sampling was done bi-monthly at seven stations at the intertidal rocky shores, west of Hormozgan Province. In this study a total of 63 species were identified, of which 15 species from seven genera belonged to green algae; 16 species from five genera belonged to brown algae; and 32 species from nine genera belonged to red algae. Coverage data of macroalgae and EEI indicate a high level of eutrophication for Saieh khosh, and Bostaneh, They are classified as zones with bad and poor ecological status, respectively. Also it has been proved that concentrations of biogenic elements and phytoplankton blooming are higher in these zones. The best values of the estimated metrics at Tahooneh and Michaeil could be explained with the good ecological conditions in those zones and the absence of pollution sources close to those transects. The values of abundance of macroalgae and EEI indicate moderate ecological conditions for Koohin, Lengeh and Chirooieh.