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In this study, soil samples were collected from ten different regions comprising the main ten cities of Kafr El-Sheikh Governorate during 2002. The Physico-chemical characteristics of the soil were investigated. The results showed remarkable differences among various sites. Twenty six genera including 40 species of algae were isolated and identified from the soil samples. They were 11 genera including 25 species of cyanobacteria and 15 genera including 15 species of green algae. The physico-chemical characteristics of soils in relation to algal distribution have also been considered.

During a recent floristic-taxonomic study on the algal flora, including diatoms, from the estuary of the Damietta Branch of the Nile in Egypt, an interesting epilithic diatom species belonging to the genus Seminavis (Naviculaceae) was collected and investigated using both light and scanning electron microscopy. This new diatom species shares morphologically some taxonomic diagnostic features with other related taxa such as S. insignis, S. robusta, and S. ventricosa. However, it still differs by having ventral central striae that are shorter and more or less straight in the middle of the smaller frustules to be clearly radiate in the larger ones and then become geniculate and only radiate near the poles, the central raphe endings are externally more distantly spaced than in the similar species, the elongate central nodule is internally less prominent, and the areola density is much denser. Therefore, we here describe it as Seminavis aegyptiaca sp. nov. Hydrochemical analyses revealed that S. aegyptiaca commonly inhabits typical marine, with a weak tendency towards brackish water, habitats. It was found to be tolerant to meso-eutrophic, nutrient-enriched conditions, based on the data available on seasonal concentrations of N and P compounds. These findings not only contribute to the inventory of Egyptian diatoms, but also increase our understanding of the autecology and distribution of this relatively poorly-known diatom genus.