- Title
- Distinguishing elephant induced thicket degradation and climate related factors in Addo Elephant National Park, Eastern Cape, South Africa
- Creator
- Mapheto, Tlhologelo James
- Subject
- Elephant – Behaviour -- South Africa -- Addo Elephant National Park
- Subject
- Wildlife conservation -- South Africa
- Date Issued
- 2023-04
- Date
- 2023-04
- Type
- Master's theses
- Type
- text
- Identifier
- http://hdl.handle.net/10948/60753
- Identifier
- vital:66741
- Description
- The Addo Elephant National Park (AENP) is an ecologically sensitive environment where the increase in elephant population, especially in a changing climate is a recipe for landscape degradation and biodiversity loss. The Park is situated in the drought prone Eastern Cape Province, however, the effects of drought on thicket vegetation is less understood. This study aimed to distinguish elephant-induced thicket degradation from the effects of climatic factors, using remote sensing, GIS, and statistical techniques. To characterise and map vegetation conditions of the reserve temporal series Landsat imagery (n = 22) from 1998 to 2018 were analysed. Vegetation states were determined using Normalised Difference Vegetation Index (NDVI) derived from the growing season of the study period. Using supervised per-pixel image classification technique, the NDVI values characterized into distinct land cover classes viz (1) Intact Thicket, (2) Transformed Thicket, (3) Degraded Thicket, (4) Bare Ground and (6) Water Bodies. Post-classification change detection and landscape fragmentation analysis was performed. Climatic data were obtained from existing weather stations and raster surface of accumulated rainfall and mean maximum temperature were developed using the Inverse Distance Weighting (IDW). Time series analysis was implemented on the NDVI and climatic condition data by plotting annual measures to indicate variable trends. Temporal trend analysis was performed on the NDVI data using the nonparametric Mann-Kendall trend analysis test to indicate thicket vegetation condition improvement and general degradation. The Residual Trend (RESTREND) approach was employed to remove the effect of rainfall on vegetation productivity. This involved using the Ordinary Least Square regression functionality in ArcMap to compute the relationship between ∑NDVI and accumulated rainfall for every pixel for the study period. The products of the regression were assessed using Pearson’s Correlation (r) at a significance level of 90% (p-value ≤ 0.1) to distinguish strong relationships. Overlay analysis was performed, using the NDVI trend slope and the correlation coefficient (r) raster surfaces, to model vegetation dynamics influenced by elephant activities.
- Description
- Thesis (MSc) -- Faculty of Science, School of Environmental Sciences, 2023
- Format
- computer
- Format
- online resource
- Format
- application/pdf
- Format
- 1 online resource (99 pages)
- Format
- Publisher
- Nelson Mandela University
- Publisher
- Faculty of Science
- Language
- English
- Rights
- Nelson Mandela University
- Rights
- All Rights Reserved
- Rights
- Open Access
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| Thumbnail | File | Description | Size | Format | |||
|---|---|---|---|---|---|---|---|
| View Details Download | SOURCE1 | Mapheto, TJ (2).pdf | 2 MB | Adobe Acrobat PDF | View Details Download |