Seasonal Dynamics of Benthic Algal Diversity and Physicochemical Characteristics in Lotic and Lentic Freshwater Ecosystems of Rampur District, India

Abstract

Vidushi Verma, Dr. Ajima Begum and Aadil Hussain

The present study investigated seasonal variation in benthic algal diversity and physicochemical characteristics, a total of three seasonal sampling periods and two freshwater habitats were analyzed to evaluate ecological differences of lotic (river) and lentic (pond) freshwater ecosystems in Rampur District, Uttar Pradesh, India. The site station 1 is Kosi River, a Ramganga tributary that streches about 35 km through district and site station 2 is water chestnut pond opposite to CRPF campus NH24. Seasonal sampling was conducted during post-monsoon, winter, and pre-monsoon periods, October 2025 to March 2026. Algal samples were collected by scrapping 3x3 cm area of submerged substratum (stone) at the location site to the depth of 48.5 cm. Physicochemical parameters including pH, conductivity, total dissolved solids (TDS), chemical oxygen demand (COD), ammoniacal nitrogen, orthophosphate, and silicate were analyzed using standard methods. Algal diversity was assessed using Shannon and Simpson diversity indices along with Pearson correlation analysis. Navicula spp. Dominated the river ecosystem whereas Spirogyra, Zygnema, and Spirulina were comparatively abundant in the pond ecosystem.

The results showed noticeable seasonal variation in water quality and algal diversity between river and pond ecosystems. Conductivity showed a strong positive correlation with TDS (r = 0.996), while Shannon diversity exhibited negative correlation with conductivity and TDS. The pond ecosystem consistently exhibited higher Shannon and Simpson diversity indices than the river ecosystem across all seasons. The findings indicate that physicochemical characteristics strongly influence benthic algal diversity and provide baseline ecological information for freshwater ecosystem monitoring in Rampur District.

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