Plankton Abundance in Relation to Physico-Chemical Parameters: A Study on Carp Fish Nursery Ponds in Jashore, Bangladesh

Abstract

The quantity and diversity of plankton communities in the water directly affect the rearing of fish fingerlings. Therefore, the present study was conducted to estimate the abundance and diversity of plankton communities including both phytoplankton and zooplankton in relation to key water quality parameters of carp fish nursery ponds in Chachra, Jashore Sadar, Bangladesh for four months from August to November 2017. Both phytoplankton and zooplankton showed a significant variation during the study period. The most abundant phytoplankton was observed in October, followed by August, November, and September. In total, 12 genera of phytoplankton from 4 different groups, Bacillariophyceae (2), Cyanophyceae (3), Euglenophyceae (3), and Chlorophyceae (4) were recorded. Total 5 major groups of zooplankton containing 20 genera were recorded such as Copepoda (4), Isopoda (1), Cladocera (9), Branchiopoda (3), Rotifera (3), where Cladocera was the most dominant. The results of PCA suggest that phytoplankton abundance is positively associated with PC1, whereas the temperature (0.59) and pH (0.74) are positively associated with PC1, and nitrate (-0.73) and phosphate (-0.64) are negatively associated with PC1. Alkalinity (0.84) and hardness (0.87) are positively, and nitrite (-0.56) is negatively associated with PC2. The zooplankton abundance is associated with neither PC1 nor PC2 rather it is associated with PC3, where DO (0.56) is positively associated. The present study revealed that plankton abundance could vary with physico-chemical parameters of fish nursery ponds.