The diversity of coral reef and soft sediment ecosystems in the Red Sea has to date received limited scientific attention. This study investigates changes in the community composition of both reef and macrobenthic communities along a cross shelf gradient. Coral reef assemblages differed significantly in species composition and structure with location and depth. Inner shelf reefs harbored less abundant and less diverse coral assemblages with higher percentage macroalgae cover. Nutrient availability and distance from the shoreline were significantly related to changes in coral composition and structure. This study also observed a clear inshore offshore pattern for soft sediment communities. In contrast to the coral reef patterns the highest diversity and abundance of soft sediment communities were recorded at the inshore sites, which were characterized by a higher number of opportunistic polychaete species and bivalves indicative of mild disturbance. Sediment grain size and nutrient enrichment were important variables explaining the variability. This study aims to contribute to our understanding of ecosystem processes and biodiversity in the Red Sea region in an area that also has the potential to provide insight into pressing topics, such as the capacity of reef systems and benthic macrofaunal organisms to adapt to global climate change.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This research has been developed using funding from the Saudi Aramco KAUST Marine Environmental Observations (SAKMEO) research program. We would like to thank Ali M. Qasem (Saudi Aramco) for information regarding the industrial facilities in the Jizan area. This paper has been reviewed and approved by Saudi Aramco Public Relation Department (Tracking number 16-3669). We wish to thank the crew of the R.V. Thuwal for their assistance in collecting the field samples. Finally we would also like to thank the two anonymous reviewers for their comments on this manuscript that improved the quality of the paper.