| Author | Vu, Hoang Hoa |
| Call Number | AIT Thesis no. AE-95-25 |
| Subject(s) | Aquaculture--Environmental aspects
|
| Note | A thesis submitted in partial fulfillment of the requirement for the degree
of Master of Science, School of Environment, Resources, and Development |
| Publisher | Asian Institute of Technology |
| Abstract | This study was conducted at Asian Institute of Technology (AIT), located at 42 km
North of downtown Bangkok. As eutrophication has become a general surface water problem,
and aquaculture discharge has been proved to be an important cause of eutrophic state in
many receiving water body, this study concerns the impact of AIT aquaculture effluents on
trophic state of the AIT canal water. The study period was relatively short, from 05 February
to 05 June 1995. Nutrient concentrations, chlorophyll a concentration and Secchi disk
transparency were used as the indicators for trophic categorization in the canal. The nutrient
contribution from aquaculture effluents was assessed based on different setting scenarios and
present status at aquaculture field.
The study showed that the average nutrient concentrations in the canal water with 5.69
mg/L nitrogen and 0.39 mg/L phosphorus were relatively high and resulted in a high
phytoplankton production (53 mg Chl-a/m3), and also the highly turbid water (33 cm Secchi
disk transparency). Many symptoms of eutrophication were observed, such as bad smell,
changing in water color, and the abundance of rooted plants, etc. The canal falls in highly
eutrophic state. Aquaculture effluents, containing an annual nutrient load to the canal of 134
kg nitrogen and 36 kg phosphorus, constitute a major source of nutrient inputs and together
with other nutrient sources, accelerate eutrophic state of the canal. Important nutrient
contribution of aquaculture effluents was also proved by higher values of nutrient
concentrations and lower values of transparency of canal water measured near aquaculture
field during the study period. From the result of setting experiment, high reduction rate of
nutrient content (65% nitrogen and 82% phosphorus) in the aquaculture effluent can be
achieved after 3 weeks retaining in aquaculture internal drainage canal. It is proposed that the
aquaculture effluent should be kelp in the treatment canal in at least 3 weeks in order to
reduce the environmental impact of the fish farming practices in aquaculture field. Long-term
studies on this subject and on other measures to improve the environmental condition at AIT
canal were recommended for future works |
| Year | 1995 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Lin, C. Kwei |
| Examination Committee(s) | Hambrey, J. B.;Sununtar Setboonsarng |
| Scholarship Donor(s) | The Government of Denmarks (DANIDA)
|
| Degree | Thesis (M.Sc.) - Asian Institute of Technology, 1995 |