International Journal of Marine Science, 2017, Vol.7, No.13, 114-124
119
Table 3 One way ANOVA showing variations in metals between locations
df
F
P
Cu
11
7.5
˂0.001
Zn
11
17.4
˂0.001
Pb
11
5
˂0.001
Cd
11
7.4
˂0.001
Fe
11
13.8
˂0.001
Mn
11
7.2
˂0.001
Co
11
2.2
0.07
The levels of Pb, Cd and Ni showed narrow but significant variations between locations. Pb ranged between
30.9±13.0 µg/g in Mangrove sediments (S3) and 76.1±11.4 µg/g in Hurghada port (H2). Concentrations of Cd
ranged from 1.9±0.5 µg/g in (Q1) to 5.1±0.5 µg/g in the old port (Q2). Nickel values were ranged between
18.3±2.1 in (G3) and 58.9±7.4 µg/g in (Q2). Although, variations of Co between locations were not significant,
there was a higher trend of Co in (S1), (S3) and (Q2). The range of Co values in different locations was 13.6-20.4
µg/g.
As shown in Figure 2, the spatial distribution of Fe and Mn was quite similar. Different stations of Ras Gharib (G1,
G2 and G3) significantly recorded low levels of Fe and Mn. In contrast, Safaga locations recorded highest levels
of them. The sediments content of Mn varied between 129.8 and 536.7 µg/g while the for Fe was 3324-19296
µg/g. Association of Fe and Mn in rocks is well known; Mn is present in divalent state associated with
ferromagnesium and accessory iron minerals (Madkour, 2005). Therefore, they are terrigenous origin and move to
marine environments through various ways.
Comparing our data with the background levels of metals (average shale and background levels in the Red Sea)
(Table 4) indicated that, all studied metals were above the background levels of Red Sea sediments (Hanna, 1992),
whereas, the concentrations of Cu, Zn, Cd, Pb and Fe were generally above the levels of average shale (Forstner
and Wittmann, 1979). The present data were also compared to levels for marine sediments from other locations
worldwide. The concentrations of Cu, Zn, and Pb in the sediments collected from the tidal flats of coastal cities of
Red Sea were lower than those recorded in sediments from other tropical regions like Singapore coast, Shanghai
tidal flat, Korean coast (Table 4). However the concentration of Cd as well as Zn, Cu, Pb (in sites H2 and Q2)
were higher than those reported in unpolluted marine sediments around the world.
Table 4 Levels of heavy metals in Red Sea sediments and other tropical locations worldwide comparing to background
concentrations
Location
Cu
Zn
Pb
Cd
Fe
Mn
Ni
Co
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