Potential of selected microalgae in bioremediation of wastewater polluted dam water: A case of Goreangab dam in Windhoek, Namibia
| dc.contributor.author | Ndura, Jennifer | |
| dc.date.accessioned | 2023-02-17T10:29:10Z | |
| dc.date.available | 2023-02-17T10:29:10Z | |
| dc.date.issued | 2022 | |
| dc.description | A research thesis submitted in fulfilment of the requirements for the Degree of Master of Science (Biological sciences) | en_US |
| dc.description.abstract | The study was aimed at determining the efficacy of freshwater microalgae in the treatment of polluted dam water with respect to the reduction of pathogen loads, as well as the concentrations of heavy metals and nutrients. Microalgae collected to treat water samples from the Goreangab Dam were collected from the Klein Windhoek River, Avis Dam as well as the Goreangab Dam. Identification of the microalgae species revealed the presence of the Microcystis species in the Goreangab Dam (control), Anabaena species in the Klein Windhoek River (treatment 1) and the Scenesdesmus species as well as the Anabaena species in the Avis Dam (treatment 2). The water samples in 12 L conical flasks each containing 1.5 L of Goreangab Dam water were treated in a greenhouse facility at the University of Namibia for a period of 12 days. Triplicate 100 ml samples were collected from the flask at day 0, day 6 and day 12 and quantitatively assessed for faecal and total coliform bacteria, heavy metals (Pb and Cd) as well as nutrients (phosphorous and nitrates). A one-way analysis of variance (ANOVA) indicated that there were no statistical differences between the mean values of Pb (p = 0.346) and Cd (p = 0.940) concentrations after treatment with microalgae. The Kruskal Wallis tests indicated statistical differences between the mean values of the nitrate levels (H(3) = 8.597 , p = 0.035) after treatment with microalgae. And the Pair Wise Comparisons indicated significant differences in nitrate uptake between treatment 1 and treatment 2 (p = 0.039) and also between treatment 2 and treatment 3 (p=0.005). However, the ANOVA indicated that there were no significant differences between the mean values of total phosphate uptake (p = 0.052) after treatment with microalgae. The results for pathogen loads in the wastewater samples indicated that there were statistical differences between the mean values of total coliform ((H(3) = 10.352 , p = 0.015) after treatment with microalgae. Further, the Pair Wise Comparisons indicated significant differences in total coliform removal between the control and the consortium (p = 0.040), between the control and treatment 2 (p=0.002) and between treatment 1 and treatment 2 (p = 0.040). Additionally, for faecal coliform presence the results indicated statistical differences between the mean values (H(3) = 10.421 , p = 0.015) after treatment with microalgae and the Pair Wise Comparisons indicated significant iii differences in faecal coliform removal between the control and treatment 2 (p = 0.002), between the control and the consortium (p=0.041) and also between treatment 1 and treatment 2 (p = 0.041). Given this evidence the use of microalgae in bioremediation is effective in the removal of pathogen loads and excessive nutrients from wastewater. | en_US |
| dc.identifier.uri | http://hdl.handle.net/11070/3601 | |
| dc.language.iso | en | en_US |
| dc.publisher | University of Namibia | en_US |
| dc.subject | Microcystis species | en_US |
| dc.subject | Scenedesmus species | en_US |
| dc.subject | Bioremediation | en_US |
| dc.subject | Pathogens | en_US |
| dc.title | Potential of selected microalgae in bioremediation of wastewater polluted dam water: A case of Goreangab dam in Windhoek, Namibia | en_US |
| dc.type | Thesis | en_US |