Limnological features and eutrophication of AIT reservoir | |
| Author | Rahman, Syed Lutfor |
| Call Number | AIT Thesis no. AQ-00-14 |
| Subject(s) | Limnology--Asian Institute of Technology Eutrophication|zAsian Institute of Technology |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. AQ-00-14 |
| Abstract | A limnological investigation was conducted in a reservoir of the Asian institute of Technology, adjacent to its flood protection dam from February to May 2000. The objectives of the study were to determine the water quality, to evaluate eutrophic condition and to predict the effect of nutrient enrichment on eutrophication. Results showed that the reservoir was thermally stratified. Dissolved oxygen was at saturation level at the surface. The level of oxygenation sharply declined with depth and was close to zero at the bottom. The pH value (8.6-8.7) was observed to be alkaline. The mean alkalinity and transparency were 153±6.3 ppm and 79±13.7 cm, respectively. Mean concentrations of total solids, total volatile solids, total dissolved solids and total suspended solids were 492± 118 μg/L, 125±3 8. 7 μg/L, 449± 124 μg/L and 40± 17 .1 μg/L, respectively. Among the major nutrient ammonium-nitrogen, nitrite and nitrate nitrogen, soluble reactive phosphorus (SRP) and total phosphorus (TP) was measured. The mean SRP concentration at surface, middle and bottom water was 20±5.1 μg/L, 41±8.6 μg/L and 24±7.6 μg/L, respectively. The TP shows a mean value of 24±6.8 μg/L. The ammonium nitrogen (NH3-N) concentration was very high, 499±116.5 μg/L, 655±138.0 μg/L and 1630±621.6 μg/L in surface middle and bottom waters, respectively. Other inorganic nitrogen concentration for nitrite and nitrate was present in small amount at 3±0.7 μg/L and 5±1.8 μg/L, respectively. Chlorophyll-a concentration shows average value of 15.6±5.8 mg/m3 . Gross and net primary production had a average value of 146.9±6.5 mg C fixed/m3/h and 87.2±6.4 mg C fixed/m3/h, respectively. Algal bioassay experiments were carried out to determine phosphorus and nitrogen limitation for phytoplankton growth. Different concentrations of nutrients (P, N) were spiked in the reservoir water sample and then incubated in a cistern at the hatchery complex. The result shows that nitrogen is more limiting than phosphorous. Excessive high values in ammonium-nitrogen concentrations, low values in dissolved oxygen content at bottom suggested that reservoir water was polluted. Although nitrogen concentration was high but low chlorophyll-a and high transparency values indicates that this reservoir was not eutrophic |
| Year | 2000 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. AQ-00-14 |
| 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 | Aquaculture and Aquatic Resources Management (AQ) |
| Chairperson(s) | Lin, Chang Kwei;Rubin, John A.; |
| Examination Committee(s) | Yi, Yang; |
| Scholarship Donor(s) | Government of Bangladesh; |
| Degree | Thesis (M. Sc.) - Asian Institute of Technology, 2000 |