The role of cyanobacteria in freshwater ecosystems of Kurdistan (Gheshlagh, Gaveh, and Sirvan rivers

Cyanobacteria play a key role in water quality assessment and ecosystem monitoring. Their study provides essential insights for sustainable water management, optimal utilization, and potential socioeconomic benefits. In this study, samples were collected from six stations: upstream of Qeshlaq (under the bridge), Qeshlaq branch before the refinery, Qeshlaq branch after the refinery, Qeshlaq branch, Gavehrood branch, and Sirvan branch. A total of ۱۳ species from the phylum Cyanobacteria were identified. Seasonal variation was pronounced: ۸ species from ۶ genera in spring, ۱۱ species from ۵ genera in summer, ۷ species from ۴ genera in autumn, and ۱۴ species from ۱۲ genera in winter. Relative abundance fluctuated markedly, increasing from spring to summer, peaking in July with rising temperatures, and declining from November through early spring. The Shannon–Wiener diversity index ranged between ۲.۲۵ and ۳.۳۳. Oscillatoria was the most dominant genus in most months, while in January, Microcystis pulvera prevailed with a density of ۸,۶۶۶,۶۶۷±۷۰۲,۳۷۷ individuals per cubic meter. Variations in cyanobacterial composition within the Sirvan–Sanandaj River ecosystem appear to be influenced by hydrological conditions, seasonal temperature shifts, and anthropogenic pollution.

کلیدواژه ها:

Cyanobacteria ، Freshwater ecosystems ، Kurdistan rivers ، Seasonal variation ، Water quality ، Oscillatoria ، Microcystis pulvera.