Seasonal variation in primary productivity in three tropical ponds

Summary Primary productivity values ranged from 1.5 to 15.8 gc/M²/day in Othakadai pond; 2.0 to 8.0 gc/M²/day in Teppakulam tank and 1.05 to 5.4 gc/M²/day in Yanamalai pond. Among the three ponds, highest annual yield was recorded in Othakadai pond (2000.2 gc/M²/yr) next in order comes Teppakulam tank (1211.8 gc/M²/yr) and lastly Yanamalai pond (810.7 gc/M²/yr). In all three ponds temperature and chlorophyll-a showed a more or less direct correlation to productivity values. Alkalinity values and productivity values showed a positive correlation in Othakadai and Yanamalai ponds, while no relationship between alkalinity and productivity could be established in Teppakulam tank.Formed part of a Ph. D. Thesis submitted to Madurai University.