English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

T levels of trace metals (Ni, Co, Cu, Fe, Zn, Cd and Pb) were determined in ten macroalgal species (green algae: Enter omorpha compressa and Cladophora albida; brown algae:, Sargassum dentifolium, Cystoseira yrica, Padina pavonia; red algae: Acanthophora najadiforrnis, Laurencia papillosa, Ceramium tenuissima, Polysiphonia figariana, Hypnea cornuta) collected from six sites along Bitter lakes (Suez Canal, Egypt). The relative abundance of trace metals in algal species decreased m the order (Fe> Zn> Ni> Cu> Pb> Co> Cd). The highest concentration of Co ( 1.17 jig/g dry wt.) and Pb ( 8.00 ug/g dry wt.) were found in brown algae C. myrica, while Cd ( 1.00 ug/g ) and Cu ( 16.92 ug/g dry wt) were "recorded in P. pavonia and S. dentifolium^ respectively. In red algae, the highest value of Ni (9.28 ug/g dry wt.), Zn (36.50 ug/g dry wt.) and Fe (502.20 ug/g dry wt.) were observed in A. najadiformis, P. figariana^and H. cornuta, respectively. According to the local variation of metals in the investigated area, the highest values of most metals (Ni, Cu, Fe, Zn and Pb) were recorded in front of Fayed (site III) which is the biggest village in the bitter Lakes area and receives agricultural and domestaic drains in addition to the effluent from the vessels crossing the Suez Canal. Inter elemental relationships were studied and showed positive significant correlation (p < 0.05) between Ni Fe (r = 0.63), Ni Zn (r = 0.47), Co Fe (r = 0.52), Zn Cd (r = 0.41) and between Zn-Pb( r = 0.49). The present study recommended that the pollution sources at Fayed, which considered as fishing and recreational marine area, must be controlled. As well as, some algal species can be used as a good target for monitoring metals pollution in Bitter Lakes. 192 Adel A. Mohamed and Hoda A. Mohamed INTRODUCTION One of the main problems to adequately evaluate natural and anthropogenic contributions of trace metals to the ecosystem, is the inherent variability in their concentrations caused by the continuous change in the conditions of the marine environment, and by dynariiics of currents and upwelling processes. An alternative that recently has been explored is the possibility of using macroalgae as bid indicators of metal concentrations in seawater (Deriton and Burdon-Jones, 1986; Haritonidis and Malea,1995; Muse et a/., 1995). The main advantage of analysing metals in seaweed tissues is that macroalgae can accumulate trace metals in concentrations which are several orders of magnitude higher than their respective concentrations in seawater (Biney, 1991; De Leon-Chavira etaL, 2003). Concentrations of trace metals associated to seaweeds have been studied in different parts of the world (Muse et al., 1995; Rainbow, 1995; El-Sarraf, 1995; Riget etaL, 1997). The area considerd in this study (Bitter Lakes) represents a huge water body of high salinity, and separating Suez Canal into two main parts. The Bitter lakes consists of two parts (Fig. l);the northern, the Great Bitter Lake, has a maximum width of 13 Km and a length of 22.250 Km., while the southern, the Little Bitter Lake, has a width of 4.5 Km and a length of 15 Km (El-Manawy, 1992). It possesses some complications to flow between Red Sea and Mediterranean. However, there has been a remarkable population development accompanied by intense urbanization, industrial activities, tourism activities and higher exploitation of cultivable land at this area and its surrounding. These activities result in increased quantity of discharged pollutants, including heavy metals. The objective of the present study is to estimate the concentration of heavy metals in different algal species growing in different localities of Bitter lakes (Suez Canal, Egypt). MATERIALS AND METHODS Five species of red macroalgae {{Acanthophora najadiformis (Delile) Papenfuss, Laurencia papillosa (C. Agardh) Greville, Ceramium tenuissima, Polysiphonia figariana (Zanardini) and Hypnea cornuta (Kutzing) J. Agardh)), three species of brown algae {{Sargassum dentifolium (Turner) C. Agardh, Cystoseira myrica (Gmelin) C. Agardh and Padina pavonia (Linnaeus) Jaillon)) and two species of green algae {{Enter omorpha compress a (Linnaeus) Nees and Cladophora albida LEVELS OF TRACE METALS IN MARINE 193 MACROALGAE FROM BITTER LAKES, SUEZ CANAL (Hudson) Kutzing)) were collected from six sites at the Bitter Lakes Suez Canal (Fig. 1). Algal samples were harvested haphazardly from the seafloor by hand or by SCUBA diving according to the depth. Samples were rinsed with clean seawater and particulate material was removed as far as possible. Air drying of algal samples, followed by grinding process. Between 0.5 and 1.5 g of dried sample of each separate sample was weighed into a 100 ml Erlenmeyer glass flask, digested with 10 ml of nitric acid at 110-135 °C. The solution was then evaporated to dryness and the digestion completed by addition of 2 ml of 1:1 mixture of nitric and perchloric acids as dicribed by Denton and Burdon-Jones (1986). The residue was dissolved in 2N nitric acid and analysed by Atomic Absorption Spectrophotometer (AAS), Concentrations of metals in seawater were extracted by APDC (ammonium pyrollidine dithiocarbamate) and MIBK (methyl isobutyl ketone) treatment as described by APHA (1989); All glassware was cleaned with dilute nitric acid and thoroughly rinsed with double-distilled water before use. Correlation matrix was calculated using Statistical program (Stat 5). RESULTS AND DISCUSSION The red algae were represented through all the investigated sites, while the brown and green algae were found at some sites. Figures (2-7) shows the concentrations of trace metals in the different separate algal species along the investigated sites. At site III (Fayed), the highest values of Ni (9.28 ug/g dry wt), Zn (36.50 ug/g dry wt.), Fe (502.20 ug/g dry wt.) were recorded in the red algae A. najadiformis, P. figariana and H. cornuta, Pb (8.00 ug/g dry wt.) and Cu (16.92 ug/g diy wt.) were in the brown algae C. myrica and S. dentifolium, respectively. Deversoir characterized by the highest concentrations of Cd (1.00 ug/g dry wt.) and Co (1.70 ug/g dry wt.) which found in the brown algae P. pavonia and C. myrica. The lowest concentrations of Cu (1.40 ug/g dry wt.), Ni (2.88 ug/g dry wt.), Pb (1.17 ug/g dry wt.) and Zn (4.40 ug/g dry wt.) were recognized at site IV in the three algal groups, while the red algae had the lowest values of Co (0.512 ug/g dry wt.), Fe (213.50 ug/g dry wt.) and Cd (0.24 ug/g dry wt.) at the sites II, V and VI, respectively. The significant high metal concentrations recorded in brown and red seaweed in site III may be attributed to the effect of Fayed sewage outlet, activities of ships waiting transit at this site along Suez Canal and agriculture run off. Fayed drain comprised high levels of most determined metals ( Abd El-Azim, 2002). Ho (1987) and El-Sarraf (1995) stated that 194 Adel A. Mohamed and Hoda A. Mohamed high seawater metal concentrations led to high bioaccumulation of these metals in macrophytes. In contrast, site IV which showed the lowest concentrations effluents where are far from any pollution sources. Haritonidis and Malea (1995) concluded that the variation of metal concentration in algae bioavailability from site to site reflects the metal concentration in different environment and physico-chemical factors (such as temperature, pH, salinity, wave exposure, light, etc.) which affect the bio-availability of algae to accumulate metals, beside the sources of pollution invaded these stations. The increase of metal concentration in algae at site III may be affected by the low value of salinity than other site in Bitter Lakes due to the invaded lower saline water (5.83 %o) from Fayed drain (Abd El-Azim, 2002). Accumulation of metals in algae was enhanced by decreasing salinity of the surrounding media, presumbly owing to competition with chloride ions for binding sites (Munda, 1984; Moore, 1991). Range and average concentrations of trace metals in the studied algal species are listed in Table (1). In the red algae, A. najadiformis the minimum concentrations of Ni, Co, Cu, Zn and Pb and the maximum of Ni, Cu and Cd were recorded, while H. cornuta had the highest values of Co and Fe. The brown alga C. myrica had the lowest concentrations of all measured trace metals at site IV. while P. pavonia showed the highest Fe, Cd and Zn levels. Enteromorpha compressa, found at site III was characterized by the maximum levels of trace metals among the other estimated green algae. Regarding these results, it is clear that different species have different affinities for certain metals. Thus, inter-locational differences in ambient metal levels should be investigated using a species or group of species common to all sites of interest. The red algae A. najadiformis and L. papillosa, were common in most stations. By comparing with L. papillosa, the distribution of metals in A. najadiformis along most stations was changed, showing that, 1) the different uptake from different populations of the species, 2) the stage of development and 3) the presence of different metallic contaminants are other important factors modifying metal bioaccumulation by algae (Karez et al, 1994). Figure (8) shows the average values of trace metals concentrations for the different algal groups. Brown algae had the lower average values of Ni, Fe, Zn and Cd, and the highest of Co, Cu and Pb. Green algae had the highest average of Fe, Zn and Cd, while the highest of Ni was found in red algae. LEVELS OF TRACE METALS IN MARINE 195 MACROALGAE FROM BITTER LAKES, SUEZ CANAL The accumulation of metals in the body of macroalgae showed a wide variation specially between highest abundant metal (Fe) and the lowest one (Cd) (El-Moselhy et al, 2006). The relative abundance of trace metals in red algal species decreased in the order Fe > Zn > Ni > Cu> Pb> Co> Cd, also the order of metals concentrations in the other two groups was slightly different recording the f

LEVELS OF TRACE METALS IN MARINE MACRO ALGAE FROM BITTER LAKES, SUEZ CANAL, EGYPT,