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Shallow hard bottom and intertidal soft bottom polychaete assemblages of the Alexandria coast, southeastern Mediterranean (Levantine Sea), were studied during a complete annual cycle in order to analyze spatial temporal patterns of variation in assemblages, and relevant factors related to polychaete distribution. The present study recorded a total of 73 species, belonging to Syllidae (22 species), Nereididae (9 species), Serpulidae (6 species), Eunicidae (5 species) and other 19 families. The assemblages experienced pronounced spatial and temporal variation throughout the study area, but spatial variation appeared more important in determining the observed patterns. Polychaete distribution related to variation of grain size and sessile macrobenthos cover suggesting that these structural variables accounted more than the physical-chemical ones (namely BOD, dissolved oxygen, organic carbon, organic matter, salinity, temperature, pH) in influencing the patterns of assemblages’ distribution. The present study is the southeastern-most one dealing with ecology and distribution patterns of hard bottom polychaetes from the Mediterranean Sea, as well as one of the few studies dealing with intertidal soft bottom polychaetes in the Levant Basin.

The phytoplankton community was studied in historically and ecologically important area on the southeastern Mediterranean coast at Alexandria, Egypt. Monthly samples were collected during January-December 2009 from 2 areas [Eastern Harbor (EH) and Kayet Bey (KB)]. A total of 162 phytoplankton species were identified in the EH and 110 species in the KB, dominated by diatoms in both areas (100 and 64 species, respectively). The phytoplankton count showed an annual average of 1.387 x 10(6) cells L-1 in the EH and 0.108 x 10(6) cells L-1 in the KB, and biomass (Chlorophyll a) of 2.4 and 2.0 µg L-1, respectively. Diatoms and dinoflagellates demonstrated clearly different roles in the phytoplankton cycle in the 2 areas, with the persistent occurrence of several toxic species, sometimes in high count, like the diatom Pseudo-nitzschia delicatissima and the dinoflagellates Scrippsiella trochoidea, Pyrophacus horologium, Prorocentrum micans, Prorocentrum triestinum, Prorocentrum cordata, Gonyaulax catenata and Protoperidinium subinerme. Regardless of the stopping of great part of the discharged wastes to the study area, it is still suffering from eutrophication all the year round, as indicated from high nutrient concentrations and intensive phytoplankton growth.

The hydrography, nutrient levels and plankton abundance were investigated monthly for a complete annual cycle in the southwestern part of Abu Qir Bay, the most polluted and biologically productive area on the Egyptian Mediterranean coast. Intense temporal and spatial variability was observed in all measured parameters characteristic of the effects of several effluents discharged into the bay. Based on the present investigation, the southwestern Bay can be divided ecologically and biologically into two parts: one including the near shore strip, which is directly affected by the waste waters, and a second comprising the southwestern part of the coastal strip and the offshore stations, both of which are relatively far away from the land-based effluents.The Bay water was characterized by low transparency (monthly average: 64-280 cm), dissolved oxygen (monthly average 2.0-6.8 mg/l) and surface salinity (monthly average: 24.8-37.9 ppt), the highest limits usually being in the offshore section. Water fertility and plankton production were high in the Bay indicating an occasionally acute degree of eutrophication, particularly nearshore. Great variations occurred in the concentrations of nutrients throughout the year, with monthly averages of 0.8-50.88 mM for ammonia, 0.42-3.28 mM for nitrite, 1.29-17.36 mM for nitrate, 0.32-3.61 mM for reactive phosphate and 1.09-33.34 mM for reactive silicate. Similarly, the abundance of both phytoplankton and zooplankton showed pronounced temporal and spatial variability, whereas the monthly average chlorophyll-a fluctuated between 2.06 and 52.64 mg/l and zooplankton between 31x103 and 248.6x103 ind./m3. However, the absolute values of all parameters indicated remarkably wider ranges of variations.Significant correlation was found between chlorophyll-a and some ecological parameters like temperature, salinity, transparency, dissolved oxygen, nitrite and between zooplankton and temperature, while there was a significant correlation between nutrient concentrations and salinity changes.

The biochemical composition (carbohydrates, protein, lipids, fatty acids and amino acids) of the nereid polychaete Pseudonereis anomala Gravier 1901, from a shallow part of the Alexandria coast (Egypt), was studied seasonally. The results revealed that P. anomala had a lower water content, higher carbohydrates and protein, but approximately similar or higher lipid levels than several other polychaetes. Fatty acids appeared to be dominated by unsaturated acids, constituting seasonally 49.6–81%, while saturated acids reached high amounts in winter and spring (23.3 and 38.3% respectively). C20:5n-3 was the major polyunsaturated fatty acid, accompanied by small amounts of C18:4n-3, C20:4n-6, C16:1n-7 and C20:1n-9. C18:0 dominated the saturated fatty acids for most of the year, except in autumn when C16:0 was the major one.

The Damietta coast is part of the Egyptian Mediterranean coast off the Nile Delta and has recently been polluted as a result of intensive human activities.The environmental parameters and protozoan community in the area were studied biweekly from January to December 2007. The results of the environmentalparameters indicated low salinity, oxic and anoxic conditions, high nutrient levels and intensive phytoplankton growth. A total of 69 protozoan specieswere identified, belonging to Amoebozoa (8 species), Foraminifera (12 species), non-tintinnid ciliates (22 species) and tintinnids (27 species). The numerical density of protozoans was high over the whole area, with annual averages between 8.2 × 103 cells m-3 and 51.4 × 103 cells m-3.Spring was the most productive season for protozoans, but several distinct peaks were observed during the year at the sampling sites. The protozoangroups showed clearly different spatial patterns in both composition and abundance: whereas amoebozoans and non-tintinnid ciliates were dominant in themore polluted areas (sites IV and V), tintinnids dominated in the less polluted areas (sites, I, II and III). Several pollution indicators wererecorded: amoebozoans - Centropyxis aculeata, Centropyxis sp., Cochliopodium sp.,Difflugia sp.; non-tintinnids - Bursaridium sp., Frontonia atra,Holophrya sp., Paramecium sp., Paramecium bursaria,Vasicola ciliata, Vorticella sp., Strombidium sp.; tintinnids- Favella ehrenbergii, Helicostomella subulata, Leprotintinnus nordgvisti,Tintinnopsis beroidea, Stenosemella ventricosa, Tintinnopsis campanula,T. cylindrica, T. lobiancoi, Eutintinnus lusus-undae.

The biometric characteristics and reproductive biology of the nereid polychaete Pseudonereis anomala were studied monthly from August 2009 to July 2010 at two ecologically different sites (Abu-Qir and El-Mex) on the Alexandria coast, south-eastern Mediterranean Sea. The maximum body length and weight showed different values at the two sites: 9.8 and 11.9 cm, and 0.77 and 1.3 g respectively. The formula of the length-weight relationship indicated allometric growth, whereas the regression equation between length to the 6th segment and weight reflected isometric growth. Immature individuals were the major component of the worm population at the two sites, making up 69.1% at Abu Qir and 66.9% at El Mex; the respective percentages of males and females at these sites were 5.8–8.1% and 22.8–27.3%. Spawning was observed all the year round with female fecundity conspicuously lower at Abu-Qir (annual average: 26556 ± 999 eggs per female) than at El-Mex (annual average: 47 955 ± 2916 eggs per female). However, oocyte size was greater at Abu Qir (diameter: up to 250 μm) than at El Mex (diameter: up to 220 μm).