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Environmental Assessment of Sediment Quality for the Main Outfall Drain and Al-Sanaf Marsh

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Al-Bahathy I. A. A. , Al-Janabi Z. Z. , Al-Hassany J. S. , Majeed O. S. , Naje A. S.

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2024

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tom Vol. 25, iss. 4

188--196

EN

This study evaluated the sediment quality of the Main Outfall Drain River in Thi-qar Government by measuring (Mn, Ni, Pb, Fe, Cr, Zn, Cd and Cu) in the sediments. Samples were collected at 4 locations between the summer of 2021 and the winter of 2022, and the results revealed that the heavy metal dominance in the Main Outfall Drain and Al-Sanaf Marsh was in the order of Fe> Mn> Ni> Zn> Cr> Pb>Cu>Cd. Among these sedimentary contaminants, Fe has the highest level in sediments. Two indices were used: sediment quality criteria (QSm) and pollution index (PI). All sites were in the third class of QSm (a possible hazard for aquatic life) because QSm> 0.5. The lowest value is recorded in site 4, and the highest value is located in site 3. The results of PI of Zn and Cu show no effected by pollution to slightly affected in all sites, Cr exhibits the same pattern as Zn and Cu except for site 3 was moderately affected in winter, while Pb caused moderate pollution effect in all sites, except site 2 and site 3 which were slightly affected in winter. Mn, Cd and Fe were seriously affected by pollution in all sites. Pollution index values of most metals (except Fe and Cr) were higher in summer than in winter, probably due to the observed dilution of the metals with anthropogenic origin by rain, leading to lower values in winter. At the same time, Fe and Cr were higher in winter than in summer due to being mostly of terrestrial origin, derived from runoff of the nearby soil by rain. The results show that the sediments of the main outfall drain suffer from large quantities of heavy metals, mainly from site 3, which may be due to receiving industrial effluent, sewage and irrigation water from the governorates through which it passes.

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Ecological assessment of heavy metals in the grey mangrove (Avicennia marina) and associated sediments along the Red Sea coast of Saudi Arabia

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Alzahrani D. A. , Selim E.-M. M. , El-Sherbiny M. M.

Oceanologia

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2018

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tom No. 60 (4)

513--526

EN

Mangroves play an integral role as a metal accumulator in tropical and subtropical marine ecosystems. Twenty-one sets of sediment samples and portions of mangroves were collected along the Saudi Arabian coast of the Red Sea to assess the accumulation and ecological risks of heavy metals. Results showed that the following mean concentrations of heavy metals in sediments: Cr (46.14 μg g−1 ± 18.48) > Cu (22.87 μg g−1 ± 13.60) > Ni (21.11 μg g−1 ± 3.2) > Pb (3.82 μg g−1 ± 2.46) > Cd (0.75 μg g−1 ± 0.87). The maximum concentrations of the studied metals were above the threshold effect level, indicating a limited impact on the respective ecosystems. The maximum concentration of Cd exceeded its toxic effect threshold, revealing a harmful risk to biota in the sediments. Based on metallo-phytoremedation, biological concentration factors were >1, suggesting that Avicennia marina can accumulate heavy metals, especially Cr and Pb. The translocation factor was above the known worldwide average. The geo-accumulation index revealed that sediments in mangrove areas ranged from moderately to heavily contaminated with Cd at Al-Haridhah and moderately contaminated at South Jeddah, Rabigh, Duba, and the wastewater treatment station near Jazan. The ecological risk index revealed that Cd could pose a relatively very high risk to the mangrove ecosystem. The present study emphasized the possibility of establishing a framework for the management of the coastal aquatic ecosystems along the Red Sea coast of Saudi Arabia.

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Spatiotemporal Variation of Heavy Metals and Pollution Indices in Groundwater Around Al-Diwaniyah Open Dump

75%

Aziz F. F. , Hussain E. K.

Journal of Ecological Engineering

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2023

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tom Vol. 24, nr 8

106--117

EN

Potential environmental hazards associated with heavy metals have been reported at Al-diwaniyah open dump in Iraq. Therefore, the levels of heavy metals and their spatial and temporal variability have been studied, in addition to pollution indices (HPI, HEI, Cd) to achieve environmental management and sustainability. Concentrations of seven heavy metals in groundwater wells at various distances around dumpsite were analyzed for the period 2022–2023 using atomic absorption spectrophotometer. Results revealed that heavy metals levels in samples examined decreased with the distance from the dumpsite W1>W2>W3 and it followed this pattern: Cd < Ni < Cr < Pb < Cu < Fe < Zn, with average concentrations in dry and rainy seasons were Zn (0.641,0.305), Fe (0.199,0.375), Cu (0.208,0.068), Pb (0.035,0.117), Cr (0.031,0.073), Ni (0.106,0.055), Cd (0.023,0.0095). On one hand, seasonal variation showed that 57.14% of heavy metals were raising in the dry season, and on the other, pollution indices showed that the groundwater taken from the W1 site was heavily polluted and unfit for consumption, while the other two sites were in low pollution category, which showed little impact of waste dumps on groundwater in these sites. Analysis results indicated that groundwater is appropriate for drinking purposes compared to the permissible limits of WHO/IQS, apart from those taken from site W1. All wells also provide water suitable for irrigation purposes based on the guidelines of the Food and Agriculture Organization (FAO). The Statistical analysis demonstrated a strong correlation between some heavy metals, in addition to the influence of sampling sites on heavy metal levels. It is recommended to expand this study to include additional regions in order to provide more environmental monitoring for groundwater and examine its potential human health risks in the study region, construct an engineering landfill equipped with leachate collector system, moreover, systematic treatment of heavy metals concentrations should be carried out regularly.