Spatial distribution and potential ecological risk assessment of some trace elements in sediments and grey mangrove (Avicennia marina) along the Arabian Gulf coast, Saudi Arabia

Abstract

<jats:title>Abstract</jats:title><jats:p>To assess trace element concentrations (Zn, Cu, Pb, Cr, Cd and Ni) in the mangrove swamps along the Saudi coast of the Arabian Gulf, thirteen samples of surface sediment and leaves of grey mangrove, <jats:italic>Avicennia marina</jats:italic> were collected and analyzed. The detected trace element contents (μg g<jats:sup>-1</jats:sup>) in surface sediments were in the following descending order according to their mean values; Cr (49.18) &gt; Zn (48.48) &gt; Cu (43.06) &gt; Pb (26.61) &gt; Ni (22.88) &gt; Cd (3.21). The results showed that the average concentrations of Cd and Pb exceeded their world average concentration of shale. The geo-accumulation, potential ecological risk and toxicity response indices demonstrated that trace elements have posed a considerable ecological risk, especially Cd. The inter-relationships between physico-chemical characters and trace elements suggests that grained particles of mud represent a noteworthy character in the distribution of trace elements compared to organic materials. Moreover, the results revealed that Zn was clearly bioaccumulated in leaf tissues <jats:italic>A. marina</jats:italic>. Dredging, landfilling, sewage effluents and oil pollution can be the paramount sources of pollution in the area under investigation.</jats:p>

Ecological risk assessment of heavy metal pollution in sediments of Nile River, Egypt

“…The Igeo values of Cd reflect unpolluted to moderately polluted northward and southward and from moderately to strongly polluted in the middle zone, recording an unpolluted degree at 21.74% of samples, unpolluted to moderately polluted at 17.39% of samples, moderately polluted at 39.13% of samples, and moderately to strongly polluted at 21.74% of samples. These findings are consistent with the results obtained by Alsamadany et al (2020). They reported that the higher contamination of cadmium might be attributed to non-point sources, such as wastewater drainage and agricultural runoff.…”

Nutrients and trace elements of semi-arid dwarf and fully developed mangrove soils, northwestern Venezuela

“…Environmental relevant trace elements concentrations, i.e. Cr, Cd, Pb and Hg, are similar to the ones observed in other mangrove soils (Alsamadany et al 2020;Angeli et al 2019;Chiu and Chou 1991;Kalaivanan et al 2017;Lacerda et al 1993;Machado et al 2014,Otero et al 2017b). These comparisons highlight the highly heterogeneity of the mangrove soils.…”

“…The observed TOC values in this study are relatively similar to mangrove soils from other semi-arid areas (Alsamadany et al 2020;Araújo et al 2012) but less than the average observed in mangroves soils from more humid areas located near the study region (Barreto 2008,Otero et al 2017b, which can be up to 20 %, and less than mangroves soils from other studies in humid regions (Chiu and Chou 1991;Marchand et al 2011).…”