Integrated approaches to assess water quality in two spots along the western Mediterranean Sea, Egypt

ABSTRACT

This study aimed to assess the status of seawater quality in the Western Mediterranean Sea, Egypt. The measurement of seawater quality was carried out at two regions, namely El Dekhila harbour and Abu Talat regions (2018–2019). The investigated parameters included pH, salinity, DO, BOD, COD, nutrient salts, metals (Fe, Mn, Zn, Cu, Pb, Cd) as well as Chlorophyll-a (Chl-a) and total phenol concentration. The range and the average values of nutrient salts (μM) in El Dekhila harbour were: 0.10–3.10 (1.50 ± 1.0), 0.6–52.60 (18.50 ± 16.4), 0.40–10.0 (3.6 ± 2.9) and 3.5–113.0 (32.3 ± 30.9) for PO₄-P, NH₄-N, NO₂-N, NO₃-N and SiO₄-Si, respectively. While in the Abu Talat region, they were 0.1–1.20 (0.32 ± 0.30), 1.34–10.8 (4.61 ± 2.5), 0.07–1.18 (0.38 ± 0.3), 0.31–30.19 (7.69 ± 8.0) and 0.10–14.44 (4.56 ± 4.0) for the same parameters, respectively. The studied metals in the two regions arranged in the following order: Fe > Zn > Mn > Pb > Cu > Cd. The metals concentration in El Dekhila harbour was two to sixfolds higher than those recorded in the Abu Talat region. The levels of Chl-a content (0.22–26.97 µg/L) and total phenol concentration (0.75–70.75 µg/L) revealed wide variations from site to another. The ecological risk of nitrogen and phosphorus data using two trophic state indices showed that the study area lies between low and high trophic state. El Dekhila harbour has the lowest water quality compared with those computed in the Abu Talat area where the difference ranged from two to five times in WQI. Analysis of the test of variance (ANOVA) showed that the mean concentrations for all parameters across the two regions differed significantly at a significance level of 0.05.

KEYWORDS:

• Phenol
• metals
• nutrient salts
• El Dekhila harbour
• Abu Talat
• Mediterranean Sea

Acknowledgement

Authors are grateful to Marine Environmental Division, National Institute of Oceanography and Fisheries (Especially head of division; Prof. Dr. Amany El Sikaily) for support this work through the research plan titled: ‘Variation in total phenol content in Seawater, sediment, macrophyte and algae with special reference to antioxidant activity in studied biota’ (2018–2019). Great thanks to Prof. Dr. Maged M. A. Hussein and Prof. Dr. Khalid Abdel Salam (NIOF) for their kind help in ANOVA test. The authors appreciate English revision by Dr. Aida Shobier. Also, thanks to the reviewers who constructive comments significantly upgraded this paper.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Notes on contributors

Gehan Mohamed El Zokm

Gehan Mohamed El Zokm: Associate professor in marine chemistry (National Institute of Oceanography and Fisheries; NIOF). She has more than 40 research papers and two books published in valuable publishers (Elsevier- Springer- Taylor & Francis and Lap Lambert). She works as reviewer for many international and impacted journals. She participated in many projects related to marine environment. Supervisor for many master and PhD. theses.

Mohamed Abdel Aziz Okbah

Mohamed Abdel Aziz Okbah: He is a professor in marine chemistry (NIOF). He has already published more than 110 research articles in peer reviewed journals most of them are in SCOPUS. He published two books. He reviewed many papers for international publishers. He was a supervisor of more than 50 theses. He participated in Environmental monitoring of the Egyptian coast of the Mediterranean Sea.

Essam Khamis El-Shorbagi

Essam Khamis El-Shorbagi: PhD. student, work as a specialist in marine chemistry lab (NIOF).