Authors: Hannah Herrero*, University of Florida, Jane Southworth, University of Florida
Topics: Remote Sensing, Africa, Earth Science
Keywords: Remote sensing, savannas, national parks, NDVI, MODIS
Session Type: Paper
Start / End Time: 9:55 AM / 11:35 AM
Room: Roosevelt 6, Marriott, Exhibition Level
Presentation File: No File Uploaded
Southern Africa savannas are an important dryland ecosystem and key areas of landscape change, and therefore conservation. This paper aims to understand how vegetation is persisting over time in and around national parks of southern Africa. Our study area encompasses southern Africa, across the landscape, inside national parks, and in buffer zones of parks. The vegetation persistence metric was developed from Moderate Resolution Imaging Spectroradiometer (MODIS) 250 m Normalized Difference Vegetation Index (NDVI) data from 2000-2016. A random walk statistic is applied to quantify trends in this indicator of vegetation health and biomass. This data is aggregated into seasons across the water year 1) March, April, and May, 2) June, July, and August, 3) September, October, and November, and 4) December, January, and February and values are accumulated through the years. The interiors of parks were compared to the buffer zones to test for differences in vegetation health across the landscape. While there were similar trends, national parks had higher amounts of positive persistence and lower amounts of negative persistence than the surrounding buffer zones. This is thought to be because they are managed landscapes protected by policy. This indicates that they are functioning favorably in terms of vegetation resilience. These outcomes may be due to a combination of climate, fire, and herbivory. This study highlights the usefulness of a continuous time-series approach for monitoring the health of savanna landscapes, and will be of particular interest to stakeholders, as it highlights that protected areas continue to be critical for conservation.