Unraveling the phytoplankton altitudinal dynamics in relation to environmental variables in a Himalayan River, Teesta, India

An investigation was carried out to comprehend the altitudinal variation of phytoplankton and their distribution pattern in River Teesta. Phytoplankton were recorded at two different altitude levels river. A total 35 genera with dominated by diatoms. The differences reflected comparatively high genus richness high-altitude region. Seasonal spectrum maximum during post-monsoon (7.67 ± 13.42 ul−1) pre-monsoon (51.6 24.52 low-altitude region, respectively. On whole, major compositions are represented as Bacillariophyceae > Cyanophyceae Chlorophyceae across seasons. k-dominance curve revealed that there no remarkable difference dominance among sampling sites 9 15 species accumulated 80% cumulative relative abundance sites. Negative gradient diversity indices (Shannon Simpson index) which implies lower exists higher altitude. Further, GAM model (R2 = 0.36) depicted statistically a nonlinear turnover against distance. significant positive relationship observed between distance Canonical correspondence analysis water variables such alkalinity, hardness, sp. conductivity, nitrate, phosphate silicate influential factors for community both altitudes river