Influence of Soil Quality, Fertilization on Live Food Production and Water Quality of Nile Tilapia, Oreochromis Niloticus, Ponds

Document Type : Original Article

Authors

1 Department of Animal and Fish Production, Faculty of Agriculture (Saba Basha), Alexandria University, Alexandria, Egypt.

2 National Institute of Oceanography and Fisheries (NIOF), Alexandria, Egypt

Abstract

Different soil types were studied for supplementing ponds with fertilizers and their effect on water quality parameters with two culture systems. The pond soils were clayey, claysandy, and sandy in three different locations in Egypt. The fish ponds were fertilized with organic fertilizers (compost) and inorganic fertilizers with a rate of 500 kg/feddan/week and
14(nitrogen: phosphorus with ratio of 4:1) kg/feddan/week, respectively. Nile tilapia Oreochromis niloticus was reared with initial body weight of (5.31g±0.03) in monoculture system with density of 22,000 fish/feddan and with grey mullet Mugil cephalus with initial body weight of (9.88g± 0.06) in polyculture system fed on commercial diet (25% crude
protein) for 240 days. The results revealed that the dissolved oxygen, total alkalinity, total hardness, and total dissolved solids increased insignificantly in clayey soil more than claysandy and sandy soil. In addition, fertilization and monoculture system raised the values not significantly. Total ammonia, unionized ammonia, nitrates (NO3), and nitrites (NO2) followed
the same trend. Total phosphorus, orthophosphate, chlorophyll”a” and zooplankton (animal/L) were significantly (P<0.05) affected by soil type of the three studied locations. Furthermore, the values of these parameters for fertilized ponds were significantly higher than unfertilized ponds for the three soil types. The same pattern was observed for monoculture system results when compared to polyculture especially in sandy soil. Accordingly, the present study indicated that fertilization were more effective in live food production for sandy soil than clay-sandy and clay soil. Also, fertilized ponds irrespective to soil type and culture system produced higher live food and final yield than unfertilized ponds,
and polyculture system was better than monoculture regardless of soil type and fertilization on live food and final produced yield. 

Keywords