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Ecology of Ismailia Canal and its branches were studied under a comprehensive program of the Freshwater and lakes Division, National Institute of Oceanography and Fisheries. Sixteen stations were selected quarterly in Ismailia Canal and its branches during 2011. Physical and chemical characters of water with surface sediment were sampled. Diatoms dominated the epipelon community, whereas chlorophyceae and cyanobacteria were rarely present. One hundred sixty-seven epipelic species were recorded. Diatoms were dominated by the centric diatoms Cyclotella spp. and Aulacoseira spp. Most frequent diatom species underwent multivariate analysis of TWINSAPN to clarify the classification of diatom species and CCA to correlate them to the most effective environmental parameters. Most species were positively affected by eutrophication, PO 4 and NH 4 , and seasonal related factor, temperature, whereas some other species were negatively affected by pH and SiO 2 . Three diatom indices were applied to assess the ecological status of the studied area. Diatom species were tested as ecological bioindicators and four diatom taxa. Cocconeis placentula, Achnanthidium minutissimum, Fragilaria construens var. venter, Navicula atomus and Nitzschia gracilis satisfied the indicator selection criteria for some ecological parameters. Trophic Diatom Index (TDI), Eutrophication Pollution Index (EPI-D) and the Pampean Diatom Index (IDP) were applied. The results of the TDI revealed that the majority of the canal stations were in the acceptable ring but showed non-significant relation with the eutrophication parameters. Both IDP and EPI-D classified the stations of the canal and its branches in the high and good category of ecological status, respectively, which were not the real state in the canal and its branches as revealed by their correlation with the eutrophication parameters. The application of diatomic indices developed in foreign country cannot be applied in Egyptian environment and the development of indices based on the Egyptian ecoregions is very necessary. ª 2014 Hosting by Elsevier B.V. on behalf of National Institute of Oceanography and Fisheries. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).

Bacterial populations within hypersaline lakes often exhibit uncultured unique species. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE), followed by sequencing of 16S rRNA gene approach was applied in order to explore, for the first time, the bacterial communities within the hypersaline Lakes, Aghormy, Zeiton and Maraqi, Siwa Oasis, Egypt. The DGGE profile displayed 12 phylotypes of 16S rRNA gene, representing the total species richness within the three studied lakes. The phylotypes were varied among lakes, but were restricted to two phylogenetic groups, Bacteroidetes, which occurred in all lakes, and Alphaproteobacetria, which showed abundance in only Lakes Zeiton and Maraqi. Single spirochete-like phylotype characterized the Lake Aghormy. A phylotype, which was recorded in both of Aghormy and Zeiton, represented a first recorded of Lewinella agarilytica in hypersaline inland lakes. Sequence homology results suggested novel indigenous bacterial phylotypes.