Author | Wirat Jiwyam |
Call Number | AIT Thesis no. AE-90-25 |
Subject(s) | Fish ponds
|
Note | A thesis submitted in partial fulfillment of the requirements
for the degree of Master of science, School of Environment, Resources and Development |
Publisher | Asian Institute of Technology |
Abstract | Two experiments on t he effect of sediment on pond fertility
and fish production (Nile tilapia, Oreochromis niloticus) were
conducted. The first was a grow-out study and examined five types
of bottom substrate. Five types of bottom substrate (detritus removed, detritus- accumulated, topsoil, deepsoil a nd. fishpond - mud) were placed in 15 rectangular concrete tanks. Fishpond - mud
substrate gave the highest average chlorophyll a concentration
(564 mg/m3) that obtained from last four weeks of culture period .
The chlorophyll a concentration in the detritus- removed
treatment was more constant (16 to 40 1 mg/m3) than in fishpond mud substrate treatment (16 to 1609 mg/m3) which increased with
the time. Fish production was also highest in t h e fishpond-mud
substrate treatment. The effect of sedimented organic matter as a
direct feed for Nile tilapia was indicated by 48 .9% higher net
production from the detritus-accumulated treatment than detritus removed treatment (983 vs 660 kg/ha/75 day).
The second experiment of accumulation/release of nutrients
was conducted on a laboratory-scale. All soil types accumulated
phosphorus . This was indicated by increasing of phosphorus in
composition of topsoil, deepsoil, and fishpond - mud which were
equal to 0.01% , 0.003% , and 0.08% respectively. All soil
types acted as a source of nitrogen for the water column. This
was indicated by decreasing of nitrogen from the compositions of
topsoil, deepsoil, and fishpond- mud which we r e equal to 0.04%,
0.003%, 0.26% respectively. |
Year | 1990 |
Type | Thesis |
School | School of Environment, Resources, and Development (SERD) |
Department | Other Field of Studies (No Department) |
Academic Program/FoS | Agricultural and Food Engineering (AE) |
Chairperson(s) | Knud-Hansen, Christopher F.
|
Examination Committee(s) | Edwards, Peter ;Lin, Chang Kwei
|
Scholarship Donor(s) | Government of Australia |
Degree | Thesis (M.Sc.) - Asian Institute of Technology, 1990 |