Contents of heavy metals in marine algae from Egyptian Red Sea coast

Seaweeds belonging to 14 different genera of Chlorophyta, Phaeophyta and Rhodophyta were analyzed to determine the levels of heavy metals in two areas of the Egyptian Red Sea coast. Among the trace metals analyzed, Mn and Zn showed the highest mass concentrations in the surface seawaters of the two studied areas. However, algae obtained from Suez area had the highest concentrations of the investigated heavy metals than those collected from Mars Alam area. Nevertheless, a high variability of the metal levels occurs among the studied algae and also between the investigated areas. Moreover, Zn was the most abundant metal in the seaweeds of the Suez area, while Pb was predominant in Mars Alam area in red and brown algae. L. farinosa had the highest average concentration factor of Zn in Suez (29161 fold), while it was 20091 fold in E. intestinalis at Mars Alam. The highest value of metal pollution index (MPI) was recoded in L. farinosa (22.0) at Suez. It represents 4.6 fold of that value recorded in L. farinosa at Mars Alam. Among green, brown and red algae in Suez, the highest values of MPI were recorded in Cladophora (mixed sub-species) and H. comuto (18.2 and 18.3), P. pavonia (16.2) and L. farinosa (22.1), respectively; while at Mars Alam, they were recorded in Cladophora (mixed sub-species) (6.6), P. pavonia (3.4) and L. farinosa (4.8), respectively.     

Potential for internal loading by phosphorus based on sequential extraction of surficial sediment in a shallow Egyptian Lake

The fractionation of phosphorus (P) in shallow Lake Maryout surficial sediments was investigated in order to understand its potential availability in relation to the eutrophication status of this lake. The rank order of P fractions was NaOH-P > HCl-P > NH₄Cl-P > BD-P. The metal oxide-bound P (NaOH-P) averaged 43% in this hypereutrophic lake and would be potentially available under low oxygen conditions. The highly available, loosely sorbed P (NH₄Cl-P) represented 20% of the sedimentary inorganic P on average, while the reductant P (BD-P) averaged 15% and is also considered highly available under low oxygen conditions. The less available calcium-bound P (HCl-P) represented 22% of sedimentary inorganic P. Lake Maryout exhibits high potential for release of P from sediment in forms available to algae, which is undesirable for eutrophication control. The range of potentially available P in tested sediments was 1,541 to 3,990 mg/kg (ppm), a very high quantity capable of supporting algal blooms independent of external loading.     

Enhancing the performance of data-driven models for monthly reservoir evaporation prediction

Environmental Science and Pollution Research - The accuracy level for reservoir evaporation prediction is an important issue for decision making in the water resources field. The traditional...     

Application of calcium alginate-PANI@sawdust wood hydrogel bio-beads for the removal of orange G dye from aqueous solution

Environmental Science and Pollution Research - This work aims to investigate the adsorption performance of orange G (OG) dye from aqueous solutions employing PANI@sawdust biocomposite enrobed by...     

Mechanical and thermo-physical characterization of mortars made with uncontaminated marine sediments

Journal of Material Cycles and Waste Management - In a context of sustainable development, civil engineering must increasingly use recyclable materials to preserve natural resources. Sediments...