Organic Manures and Phytoplankton Production
A. O. Iyiola
Department of Aquaculture and Fisheries Management, University of Ibadan, Nigeria.
A. P. Ojo-Awo *
Department of Aquaculture and Fisheries Management, University of Ibadan, Nigeria.
*Author to whom correspondence should be addressed.
Abstract
Phytoplankton are primary producers in aquatic ecosystem and play an important role in the food chain or web in aquatic ecosystem. This research compared rate of production of plankton from poultry droppings and cow dung against control (no manure) and the impacts on the physico-chemical parameters. Daily sampling, identification and counting as well as analysis of physico-chemical parameters were carried out. Phytoplankton species observed were Pediastrum, Chlorella, Spirogyra and Closterium. Poultry droppings stimulated the highest production while the least was the control (no manure). The mean values for temperature were 27.4ºC for poultry droppings, 27.1ºC for Cow dung and 27.3ºC for the Control. pH recorded 7.5 for Poultry droppings, 7.0 for Cow dung and 7.1 for the Control. Dissolved oxygen was 5.0 mg/l throughout the culture systems. Ammonia recorded 0.9 mg/l for Poultry droppings, 0.4 mg/l for Cow dung, 0.0 mg/l was recorded for Control. Nitrite was 3.5 mg/l for Poultry droppings, 0.25 mg/l in Cow dung, 0.5 mg/l and 0.1 mg/l in Control. Nitrate was 80 mg/l for Poultry droppings, Cow dung was 22.5 mg/l while 12.5 mg/l was the Control. Poultry droppings produced the highest number of phytoplankton species as a result of the high Nitrate and Phosphate content which is a mineral stimulates phytoplankton production. ANOVA results showed significant differences (P<0.05) in phytoplankton production between Poultry droppings, cowdung and control.
Keywords: Phytoplankton, organic manures, water quality