A Preliminary Observation on Water Quality and Plankton of an Earthen Fish Pond in Bangladesh: Recommendations for Future Studies

Abstract

The present study provides a characterization of water quality and plankton samples in earthen fish pond in Rajshahi, Bangladesh. Sampling was done over a period of six months, running from October, 2004 through March, 2005. All the water quality parameters were within the optimal ranges for plankton productivity. Temperatures varied from 19.75 to 27.25 degrees C; transparency, 24.75-29.50 cm; pH, 6.62-7.85; Dissolved Oxygen (DO), 3.87-5.85 mg L(-1); free CO2 5.25-7.25 mg L(-1) and bicarbonate (HCO3) alkalinity, 81.25-147.5 mg L(-1). Analyses of plankton samples recorded a total of 5 classes phytoplankton viz.; Bacillariophyceae, Chlorophyceae, Cyanophyceae, Dinophyceae, Euglenophyceae and 2 classes of zooplankton; Crustacea and Rotifera. The phytoplankton population was comprised of 17 genera belonging to Cyanophyceae (5 classes, 34.47%), Bacillariophyceae (3, 13.87%), Cyanophyceae (3, 34.48%), Euglenophyceae (3, 10.68%) and 1 to Dinophyceae (6.50%). The zooplankton population consisted of 10 genera belonging to Rotifera (4, 40.13%) and Crustacea (6, 59.87%). Phytoplankton and zooplankton abundance varied from 60800 to 239400 units/l and 7620 to 12160 units/l, respectively. It is concluded that the phytoplankton groups provide the main support for earthen pond aquaculture in the pond compared to zooplankton classes. The information provides for more research to compare water quality and pond plankton characteristics in earthen aquaculture systems with and without fish stocking. Further studies on the seasonal changes of water quality parameters and its effects on plankton production in the fish ponds and all year extended monitoring is recommended in future studies.

Inter-annual and seasonal variations in hydrological parameters and its implications on chlorophyll a distribution along the southwest coast of Bay of Bengal

“…During winter monsoon period, on the other hand, the strong northeasterly winds and cool sea surface as well as cloud covers due to northeast monsoon reduces the incoming solar radiation and results in winter cooling over the southwest BoB. The correlation analysis shows negative correlation between chlorophyll and SST (r=-0.088, P<0.05) during the study period, due to the increased light intensity and SST which tend to reduce the phytoplankton population, a clear evidence reported by Hossain et al (2007). During summer, increasing light levels and strong stratification due to more surface heating and less wind stress hamper the nutrient supply to the surface waters and result in lower biological production (Kumar et al, 2002).…”

Effects of Seasonal variation on Growth Performance of Mirror carp (Cyprinus carpio Ver. specularis) in Earthen Nursery Ponds

“…Hossain and Islam (2006), reported the SGR of prawn, catla, rohu and silver carp ranged from 3.99 to 4.26, 3.71 to 3.83, 2.49 to 2.55 and 2.44 to 2.59% respectively. The specific growth rate in summer season was higher because the environment is suitable for fish.…”

Diversity and community structure of fish, plankton and benthos in Karangsong Mangrove Conservation Areas, Indramayu, West Java, Indonesia

“…Inorganic elements such as trace metals can be absorbed into the tissues of aquatic organisms through the food chain. Dissolved phosphorous is probably the most important factor affecting the water quality, because it is a driver of phytoplankton growth (Hossain 2007). …”