Distribution and Diversity of Zooplankton with the Environmental Factors in some Lentic Water bodies from Bihar, India

Freshwater ecosystems harbour zooplankton that fills as a significant part of the food chain of water bodies. Tragically, these ecosystems and diversity therein are compromised by a lot environmental pressure and pollution. An investigation was led from January 2018 to December 2019 to examine variation in zooplankton with the physicochemical profiles of Katira pond and Surya Mandir pond, Arrah keeping standard methods. Observations showed that during summer season water temperature, total alkalinity, hardness and chloride were observed more during summer season followed by the rainy , post-rainy and rainy season but a reverse pattern was observed for pH, dissolved oxygen, nitrate and sulfate. The water temperature demonstrated a positive relationship with total alkalinity, hardness and chloride whereas a negative correlation with pH, dissolved oxygen, nitrate and sulfate. 43 genera of zooplankton together with 15 rotifers, 10 protozoa, 9 cladocerans, 6 copepods and 3 ostracods were related to a numerical density from 1 to 538unit/L. The density of zooplankton was more distinguished throughout the colder time followed by summer, pre-rainy and rainy seasons. Zooplankton density showed a positive relationship with pH, dissolved oxygen, nitrate and sulfate however a negative relationship with water temperature, chloride, total alkalinity and hardness. Statistical analysis inferred critical contrasts in the spatial variation over physicochemical parameters (excluding nitrate), zooplankton groupings and biodiversity indices (excluding Simpson index). The observed estimates of the Shannon-Weiner index, Margalef Richness Index, Pielou’s Evenness Index and Simpson index showed moderate to high diversity of zooplankton and moderately polluted conditions of these ponds.