Culture potential of green mussel based on bio-physical variables and food availability in Rezu Khal, Cox’s Bazaar

Abstract

ABSTRACTS Bivalve aquaculture is an important source of affordable animal protein for coastal community. The success and sustainability of this industry is highly influenced by the suitability of the environment in which it is being carried out. The present study was carried out to evaluate whether it would be possible to culture green mussel Perna viridis in Rezu Khal, Cox’s Bazar. In this study, site suitability of Rezu Khal for green mussel farming was evaluated based on the year-round variations of physico-chemical water quality parameters, and quantitative and quantitative abundance of plankton community. Five Stations were selected chronologically from upstream to downstream at specific interval of distance. The water and plankton samples were collected from these five Stations of the Rezu Khal on monthly interval from April 2017 to March 2018. The results showed that most of the physico-chemical water quality parameters (temperature, dissolve oxygen, pH, turbidity and dissolved nutrients such as nitrite, nitrate, phosphate and ammonia) in all Stations were considered as suitable for green mussel culture. The water depth was moderate in Stations 4 and 5, and very low in other Stations for green mussel culture. Salinity fluctuation (2 to 34.5 ppt) was also a major issue in all Stations of Rezu Khal for green mussel culture. In Rezu Khal, a total of 59 genera of phytoplankton and 16 genera of zooplankton were identified, and their abundance was varied from 15.4×103 to 37.5×103 cells/L depending on the seasons and the Stations. The phytoplankton community was mostly dominated by Bacillariophyceae (83% of the total phytoplankton count) with Skeletonema and Coscinodiscus as the dominant genera. After taking all the water quality parameter qualitative and quantitative abundance of plankton, the station 1 and 2 (located on the upstream) less recommended for green mussel culture and station 3, 4 and 5 (located on the downstream) exhibited medium site capability rating point. In conclusion, downstream Stations (3, 4 and 5) of Rezu Khal are capable and moderately suitable for green mussel farming.