Distribution and biodiversity of macro-benthic fauna in relation to some heavy metals at the Great Bitter Lakes, Suez Canal, Egypt

摘要

The present study aims to document the diversity and density of benthic fauna in Great Bitter Lakes through their spatial and temporal changes in this important area from spring 2016 to winter 2017. Eleven sampling stations representing most of the area of the Great Bitter Lakes were selected. The results showed that there was 41 species and an annual density of 104,680 organisms/m2of macro-benthic fauna belonging to five phyla in the studied area. Eighteen species from polychaetes, 12 molluscs, 7 species from crustaceans, 3 echinoderms and one species belonging to cephalochordate were recorded. With the exception of the most dominant species of the lakes,Modiolus auriculatus, which was represented by an annual average of 6822.91 organisms/m2, the onshore stations were the highest in density and diversity than offshore stations (35 and 28 species with an annual density of 18,873 and 10,755 organisms/m2, respectively). The value of heavy metals in surface water was within the following sequence; Fe?>?Zn?>?Cu?>?Pb?>?Mn?>?Cd. While in the sediments were arranged as follows: Fe?>?Mn?>?Zn?>?Cu?>?Ni?>?Pb?>?Cd. In the studied area, the medium sediments (?2+?3) recorded the highest percentage (61.34%) of the total percentage of sediment.