Asian Journal of Biology

Freshwater algal diversity was assessed in four selected ponds in the Manjhanpur region of Kaushambi District, Uttar Pradesh, from March to October 2025. The study aimed to document taxonomic diversity and seasonal occurrence in relation to selected physicochemical water parameters. Water and algal samples were collected from the ponds, cultured in BG-11 medium, and examined using morphology-based identification. Water temperature, pH, dissolved oxygen, and biological oxygen demand were also evaluated. Eighteen algal taxa belonging to Cyanophyceae, Chlorophyceae, Bacillariophyceae, and Euglenophyceae were recorded. Cyanophyceae was the dominant group, comprising eight taxa, followed by Chlorophyceae with six taxa; Bacillariophyceae and Euglenophyceae each comprised two taxa. The recorded physicochemical values ranged from 6.5 to 8.3 for pH, 24.5 to 35.5°C for temperature, 5.6 to 6.7 ppm for dissolved oxygen, and 2.5 to 6.5 ppm for biological oxygen demand. Algal diversity was greatest during the monsoon period. Oscillatoria and Phormidium showed the highest reported frequencies, whereas Aphanocapsa and Fragilaria showed the lowest. The occurrence of pollution-tolerant taxa, together with seasonal variation in water characteristics, indicates that algal assemblages can contribute to the ecological assessment of these ponds. The study provides baseline information on freshwater algal diversity in the Manjhanpur region and supports the need for broader seasonal monitoring and complementary taxonomic approaches.