L. Rabaoui, M. Cusack, V. Saderne, P.K. Krishnakumar, Y. Lin, A.M. Shemsi, R. El Zrelli, A. Arias-Ortiz, P. Masqué, C.M. Duarte, M.A. Qurban
Science of the Total Environment, (2020)
Coastal vegetated habitats, Sedimentary record, Trace elements, Arabian Gulf, Saudi Arabia
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.