International Journal of Marine Science, 2017, Vol.7, No.23, 214-228
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Sediments are the principal sink of heavy metals in the aquatic coastal system, but under certain chemical and
physical conditions metals can readily release into the water column again and become a source of metal to
marine organisms (Dickinson et al., 1996; Dar, 2014). Therefore, the distribution of heavy metals in the sediments
can serve as environmental indicator of current and past condition of the pollutant discharged in the surface
marine sediments (Förstner and Salomons, 1980; Abu-Hilal and Badran, 1990). Because of metals are not equally
distributed in the different sediment fractions, heavy metals were widely determined in the finer grains in order to
minimize the variation effect (Salomons and Förstner, 1984). Finer particles usually contain high concentrations
of heavy metals due to possessing large surface area and high association with clay and organic matter (Irvine and
Birch, 1998; Yu et al., 2012). It is important to evaluate the ecological risk of heavy metals in fine sediments, not
only because of their high content of heavy metals but also because they can readily move by the wave
winnowing and currents to adjacent places which may host biologically sensitive communities (Dar et al., 2016a).
Assessment of heavy metal levels only cannot describe the ecological risk to marine environment or evaluate the
contribution ratio from terrestrial and anthropogenic sources (Zhu et al., 2012). Therefore, some methods were
adopted to evaluate the biological and ecological risk of heavy metals in marine sediments such as comparing to
sediments quality guidelines (SQGs), and applying several quantitative geochemical indices like pollution load
index, enrichment factor and geo-accumulation Index (El Zrelli et al., 2015).
Maritime activities in the Egyptian ports of the Red Sea proper were concentrated in three main locations at
Hurghada, Safaga and Qusier. Three main activities involved in the port area of Hurghada; passengers, fishing
berth and tourist marina. These activities in addition to effluents of desalination plant and sewage seepage as well
as Hurghada shipyard are the main sources of pollution. Safaga has the largest port in the Egyptian Red Sea proper;
it plays an important role in the Egyptian international trade. It is characterized by intense shipping traffic with
frequent loading and dumping operations. The port involves passenger terminal, terminals for cargo, bauxite, coal,
grains, quartz and orthoclase shipment. Qusier has the oldest phosphate port in the Red Sea. The marine area
surrounding the ports was frequently affected by wastewater seepage and anthropogenic terrestrial runoff. During
the last years, a number of studies have assessed the levels of heavy metals in the Red Sea coastal sediments (e.g.,
Madkour, 2005; Salem et al., 2014, El-Metwally, 2015; Dar et al., 2016a; 2016b; El-Metwally et al., 2017) and
harbours (Madkour, 2004; Madkour and Dar, 2007; Mansour et al., 2011; 2013). However, regardless the rapid
expansion in ports and harbour areas of the Red Sea, but the ecological risk of different port facilities on
sediments quality has not been evaluated before.
The objective of the present study is to determine the contribution of maritime and land-based activities at the
main ports of the Egyptian Red Sea on the levels and distribution of heavy metals in the fine sediments in order to
evaluate their environmental risk in the marine habitats.
1 Materials and Methods
1.1 Study areas
Thirty three sampling sites were selected in front of the main ports along the Egyptian Red Sea proper (Figure 1).
The sediments samples were collected using a Van Veen grab sampler and small boat in the marine area off the
main ports at Hurghada, Safaga and Qusier with depth variation between 5 and 17 m. These sampling sites were
grouped in eleven stations for covering the different maritime activities (passengers, shipyard, tourist activities,
gains shipment, phosphate shipment, bauxite shipment, coal shipment, fishing, quartz and orthoclase shipments).
At Hurghada Port, 4 stations were selected covering the whole marine area off the port; passenger wharf (sites H1
–H3), shipyard (H4), fishing berth (H5-H8) and the touristic marina (H9-H11). Five stations at Safaga Port; grains
platform (S1-S2), passenger wharf (S3-S5), bauxite platform (S6-S7), coal platform (S8-S9) and the platform of
quartz and orthoclase represented by the stations (S10, S11 and S12). At Qusier Port, station I (Q1-Q4) was
located in marine area off of the old port; meanwhile station II (Q5-Q10) was covered the fishing basin.
