Anthropogenic-induced acceleration of elemental burial rates in blue carbon repositories of the Arabian Gulf

by LotfiRabaoui, MichaelCusack, Vincent Saderne, Periyadan K. Krishnakumar, Yu-JiaLin, Ahsan M.Shemsi, RadhouanEl Zrelli, ArianeArias-Ortiz, PereMasqué, Carlos M. Duarte, Mohammad Ali Qurban
Research article Year: 2019 DOI: https://doi.org/10.1016/j.scitotenv.2019.135177

Bibliography

Rabaoui, L., Cusack, M., Saderne, V., Krishnakumar, P. K., Lin, Y. J., Shemsi, A. M., ... & Qurban, M. A. (2020). Anthropogenic-induced acceleration of elemental burial rates in blue carbon repositories of the Arabian Gulf. Science of The Total Environment719, 135177.

Abstract

Along the past century, the Arabian Gulf has experienced a continuous and fast coastal development leading to increase the human pressures on the marine environment. The present study attempts to describe the historical changes of trace elements in the sediments of vegetated coastal habitats in the western Arabian Gulf. 210Pb–dated sediment cores collected from seagrass, mangrove and saltmarsh habitats were analyzed to evaluate historical variations in concentrations and burial rates of 20 trace elements (Al, As, Ba, Ca, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Na, Ni, P, Pb, S, Sr, V and Zn). The highest correlations (Spearman correlation coefficients ≥0.51) were found between crustal elements (Al, Fe, Co, Cr, K, Na, Mg, Mn, Ni, V, and P), suggesting a common crustal source in the Gulf. The increased concentrations of these crustal elements in modern marine sediments of the Arabian Gulf seem to be linked to increased mineral dust deposition in the area. Over the last century, both elemental concentrations and burial rates increased by factors of 1–9 and 1–15, respectively, with a remarkably fast increase occurring in the past six decades (~1960 – early 2000). This is most likely due to an increase in anthropogenic pressures along the Gulf coast. Our study demonstrates that sediments in vegetated coastal habitats provide long-term archives of trace elements concentrations and burial rates reflecting human activities in the Arabian Gulf.

Keywords

Coastal vegetated habitats Sedimentary record Trace elements Arabian Gulf Saudi Arabia