RESUMEN
The soil algal flora of the canal bank habitat at Sohag District, Egypt, together with the edaphic, climatic factors and physicochemical characters of the soil were seasonally studied during the year 1992. The maximum values of electric conductivity, sodium, potassium, calcium, chloride, sulfate, bicarbonate, soluble, silicate and ammonia-nitrogen were recorded in summer. The highest values of magnesium and available phosphate were detected in autumn. The maximum values of algal biomass [100.3 kg/ha] was estimated in winter. This was accompanied by maximum values of organic carbon and nitrate nitrogen. On the other hand, the minimum values of algal biomass [9.1 kg/ha] and organic carbon were detected. Thirty-four species were isolated and identified, 24 Cyanophyta, 8 Chlorophyta, one Xanthophyta and Bacillariophyta. The blue-green algae frequently encountered constituted 70.58% of the total population of all soil samples with predominance of Anabaena, Calothrix, Lyngbya, Nastoc and Phormidium. Green algae were mostly represented by Asterococcus chlorella and Kirchneriella. Both Xanthophyta and Bacillariophyta were represented by one species, Hanzschia and Tribonema, respectively