Evaluation of periphyton quantity on different natural substrates in Earthen lined pond

Abstract

Experiments were conducted in outdoor earthen lined pond to study periphyton quantity on three types of natural substrates such as split bamboo pole, coconut coir and coconut shell, which was placed inside the earthen lined pond filled with seawater for duration of 45 days. Observations were made in every 15th day for growth of periphyton both qualitatively and quantitatively on the three natural substrates and physico-chemical properties of selected pond water such as transparency, water temperature, salinity, pH, Dissolved oxygen, Ammonia (NH3-N), Nitrite (NO2-N), Nitrate (NO3-N), BOD and Chlorophyll ‘a’ were recorded during periphyton samplings. The periphy-ton quantity (34562 ± 671 cells / cm2) observed for coconut coir was higher than the split bamboo pole (33104 ± 810 cells / cm2), and coconut shell (21194 ± 872 cells / cm2) in the final day of the experiment. One way ANOVA of the data collected clearly affirmed that significant differences were observed (P < 0.05) in periphyton quantity among the three substrates tested. A total 16 phyto-periphytic microalgae (Bacillariophyceae – 10 types, Dinophyceae – 4 types and Cyanophyceae – 2 types) and 10 Zoo-periphyton (Copepod- 4 types, Meroplankton – 4 types and Tintin-nidae – 2 types) were recorded from these three substrates. Among the different phyto-periphytic microalgae, Bacil-lariophyceae group were found to be more (Split bamboo pole – 72%, Coconut coir – 73% and Coconut shell – 71%) on three substrates studied. Further, coconut coir was found to be best substrate than split bamboo pole and coconut shell, which can be utilized by fin and shellfishes as natural food.