Abstract
ABSTRACT
In the present paper, we have examined two perennial freshwater wetlands in Bhagalpur district, Bihar (I) Jichho Pond in Pirpainti Block (Pond-I: Latitude-N 25°18'56.25"/Longitude-E 087°25'53.94"), and (II) Purandaha Pond in Shahkund Block (Pond-II: Latitude-N 25°09'35.46"/Longitude-E 086°48'22.62"). Both the wetlands provide a variety of services for the human population, which include water for drinking and irrigation, fishing, and other domestic uses. The objective of the present study was to generate baseline data on water quality and phytoplankton diversity of the above mentioned two ponds. Water parameters such as temperature, pH, electrical conductivity, dissolved oxygen, alkalinity, total hardness, chloride, nitrate-nitrogen, phosphate-phosphorus, COD and BOD for both the ponds were studied on seasonal basis (2020 – 21). Most of the water parameters were found to be well within permissible limit except that of BOD (3.1-4.8mg/L) and COD (28.8-82.3mg/L) which were in higher range crossing the permissible limit as prescribed by WHO (2017) and BIS (2012). In this study, a total of 91 species belonging to 42 genera of phytoplankton (algal taxa) have been identified from both the ponds. Phytoplankton taxa in Pond – I was found to be relatively more diverse than in Pond-II. Among the identified phytoplankton species, Chlorophyceae (38.88%) formed the dominant group followed by Bacillariophyceae (29.62%), Cyanophyceae (20.37%) and Euglenophyceae (11.11%) in Pond-I, whereas in Pond-II, Chlorophyceae (39.58%) formed the dominant group followed by Bacillariophyceae (31.25%), Euglenophyceae (20.83%) and Cyanophyceae (8.33%). Phytoplankton density was found to be maximum during summer season and minimum during monsoon season in both the ponds. Species like Scenedesmus quadricauda, Scenedesmus obliquus, Scenedesmus dimorphus, Chlorella vulgaris, Pediastrum duplex, Coelastrum microporum, Synedra ulna, Synedra acus, Nitzschia palea, Cyclotella meneghiniana and Oscillatoria princeps were recorded from both ponds. According to Palmer's (1969) pollution index, the presence of algal species like Chlorella vulgaris, Oscillatoria princeps, Euglena gracilis, Nitzschia palea and Scenedesmus quadricauda suggested that both the ponds under investigation were organically polluted and are advancing towards the eutrophic condition