EFFECT OF USING PERIPHYTON SUBSTRATE (BAMBOO STEMS) ON WATER QUALITY, PHYTOPLANKTON, ZOOPLANKTON, PERIPHYTON AND GROWTH PERFORMANCE FOR TILAPIA, MULLET AND
CATFISH IN EARTHEN PONDS
Ibrahim M. Shaker1; Mohamed Y. Abou Zeied2 and Ahmed M. Batran1
1Central Laboratory for Aquaculture Research, Agriculture Research Center, Ministry of Agriculture, Egypt.
2World Fish Center (ICLARM).
Corresponding author: [email protected]
Received 16/ 6/ 2013 Accepted 28/ 7/ 2013
Abstract
A polyculture trial was conducted in earthen ponds at Kafer El-Sheikh Governorate – Egypt to compare traditional aquaculture techniques. The study was carried out in fifteen earthen ponds (1000m2 each) with five treatments each in three replicates: control treatment (artificial feed only 25%; mineral without substrate; mineral with substrate (Bambusa sp.); traditional fertilization without substrate and traditional fertilization with bamboo substrate. The total number of Oreochromis niloticus 75% mixed sex, Mugel cephalus 20% and catfish Clarias gariepinus 5% with (mean body weight 10 ±1.1g) fish species per pond were 3750, 1000and 250 for tilapia, mullet and catfish, respectively in each pond. Grow-out duration was 150 days. Water quality, phytoplankton; zooplankton and periphyton were monitored throughout the experiment. Significantly higher concentrations of nitrogen compounds (NH4, NH3, NO2 and NO3) were recorded in traditional and mineral fertilization without substrate than with substrate treatments and feed only. Dissolved oxygen significantly increased in substrate treatments than others due to the consumption by phytoplankton. The chlorophyll- a concentration of pond water was significantly higher in the traditional and mineral fertilization treatments without substrate than in the other treatments. The net primary productivity (NPP) and gross primary productivity (GPP) significantly increased in traditional fertilizers with and without substrate treatments than in mineral fertilizers with and without substrate and feed only. Periphyton significantly increased NPN and GPP. The pheophytin -a chlorophyll -a total number of phytoplankton and zooplankton significantly increased in traditional and mineral fertilization treatments without substrate than in with substrate treatments. Dry matter content increased significantly with depth up to 50 cm, and then decreased gradually to the end. Periphyton chlorophyll a concentrations per unit surface area were significantly different among the substrate depths and decreased with increasing water depth.
The total fish production was 2948; 3799; 4144; 2803 and 3192 kg/ feddan for feed only; traditional without and with substrate treatments; mineral fertilizer without and with substrate, respectively. The fish production was significantly higher in substrate treatment than without substrate treatments and feed only treatments. Survival rate was significantly increased in substrate treatments (traditional and mineral fertilization) than in without substrate (traditional and mineral fertilization) and feed only. The bamboo substrate improved water quality, survival rate and total production of fish.
Key Words: Periphyton, Water quality, Phytoplankton, Zooplankton, Growth performance, Fish species, Fresh water.