- Title
- Environmental management of wetlands on an urban periphery: the case of Bay West
- Creator
- Domoney, Nicola Leah
- Subject
- Wetland management -- South Africa -- Nelson Mandela Bay Municipality
- Subject
- Remote sensing Chlorophyll
- Date Issued
- 2018
- Date
- 2018
- Type
- Thesis
- Type
- Masters
- Type
- MSc
- Identifier
- http://hdl.handle.net/10948/30854
- Identifier
- vital:31183
- Description
- South Africa is a semi-arid country and thus depends on sound management of its water resources. Wetlands, despite their importance to water resource storage and water quality, among their other ecological and social significance, remain the most threatened of South Africa’s ecosystems. One of their greatest threats is encroachment by urbanisation. This occurs because wetlands, and especially ephemeral urban periphery wetlands, are overlooked. This study’s main objective was to determine the water quality and health of the wetlands adjacent to the newly established Bay West development on the western urban periphery of Nelson Mandela Bay. Wetlands are difficult to access and it is time-consuming to assess them. Remote sensing, however, overcomes this challenge and is cost-effective and time-considerate. It was the aim of this study to assess the health of the peri-urban wetlands on the Bay West periphery in order to formulate an appropriate environmental management plan, and remote sensing was tested as an effective method for wetland health management. It was found that the wetlands closer to the urban residential area (Sherwood suburb) were far more impacted than the wetlands nearer to Bay West Mall. Wetlands Six to Eight were higher in all parameters of pH, total dissolved solutes (TDS), salinity, conductivity and chlorophyll a concentration than Wetlands One to Five located further away from the urban area. A correlation with distance away from the urban area found a strong inverse relationship with between distance and the water quality factor, yielding a correlation coefficient of (<-0.7) in 2017 and (<-0.9) in 2018 with regard to TDS, salinity and conductivity. This, therefore, suggests that the wetlands’ health deteriorates towards the urban area. TDS, salinity, pH and conductivity correlate highly with chlorophyll a concentration at (>0.70). There was significant difference in pH in the year 2017 between the Bay West wetlands and the reference wetland (p<0.05; df=19; f= 3.56; n=3) and in 2018 (p<0.01; df=22; f= 8.90; n=3). No significant difference was found between the wetlands for dissolved oxygen. TDS between the wetlands was found to be significantly different in the year 2017 (p<0.01; df=23; f= 44.16; n=3) and 2018 (p<0.05; df=22; f=2.62; n=3), where conductivity and salinity returned the same p value for 2017 and 2018 as TDS respectively. There was a significant difference in chlorophyll a between the Bay West wetlands in 2017 (p<0.05; df=20; f=3.29; n=3) and Wetland Seven measured eutrophic at 22.45 mg/L-1. Remote sensing red band values and the field sample absorption values were highly correlated at R2= 0.5. Chlorophyll a content of wetland water correlated with NDVI data at R2= 0.6. Thus, remote sensing proved to be a successful estimator for wetlands health analysis and a proxy for wetland management. These results yielded an environmental management plan where monitoring water quality via chlorophyll a indicated health levels of the wetlands via trophic state.
- Format
- x, 104 leaves
- Format
- Publisher
- Nelson Mandela University
- Publisher
- Faculty of Science
- Language
- English
- Rights
- Nelson Mandela University
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| Thumbnail | File | Description | Size | Format | |||
|---|---|---|---|---|---|---|---|
| View Details Download | SOURCE1 | Nicola Leah Domoney.pdf | 6 MB | Adobe Acrobat PDF | View Details Download |