Study of molluscan diversity with correlation to physico-chemical parameters of water in the Burhi Gandak river, Bihar

Abstract

The current study aimed to assess the molluscan diversity in correlation with physico-chemical parameters in the Burhi Gandak River of Bihar. Mollusc species were collected from three sampling sites- Pilakhi, Dholi and Shaidpur located in Muzaffarpur and Samastipur districts during the study period from November 2021 to August 2022. Molluscs were collected by handpicking and using hand nets. Also, water samples were collected and their physico-chemical properties were analysed as per established standards. The diversity of mollusc species was measured using Simpson, Pielou, Shannon-Wiener and Margalef's richness indices. A total of 12 mollusc species were identified, comprising 9 species from Gastropoda and 3 from Bivalvia. Bellamya bengalensis (25.17%) and Lamellidens marginalis (19.33%) species were more prevalent and widely spread in all water bodies. There is a positive correlation between molluscan abundance and the level of dissolved oxygen (r = 0.836, p < 0.01), temperature (r = 0.64, p < 0.05), hardness (r = 0.80, p < 0.01), and ammonia (r = 0.69, p < 0.05) were found. The study highlights that molluscan diversity in the Burhi Gandak River is significantly influenced by key physico-chemical factors. Conservation efforts are essential to maintain ecological balance and biodiversity.