Description

Abstract: The effect of weekly applications of similar quantities of nitrogen and phosphorus from three different sources on the production of Oreochromis niloticus (10 000/ ha) was studied in 0.1-ha earthen ponds. Layer chicken litter (500 kg total solids (TS)/ ha), dairy cow manure (1020 kg TS/ ha) and chemical fertilizer (46-0-0 at 30.6 kg/ ha and 0-46-0 at 62.6 kg/ha) were applied weekly. Mean total net production after 150 days was greater with chicken litter (1759 kg/ha). Differences in fish production were explained in terms of net and gross primary productivity and community respiration.