Authors: Hannah Herrero*, University of Tennessee
Topics: Africa, Remote Sensing, Land Use and Land Cover Change
Keywords: Remote sensing, savanna science, vegetation dynamics, conservation, Africa
Session Type: Paper
Presentation File: No File Uploaded
Understanding vegetation trends in conservation areas of Africa is critical because they are the ecological and socioeconomic drivers of the region. Gorongosa National Park in Mozambique formed under very unique conditions. Park management in the last ten years has focused on mammal restocking, but monitoring and managing vegetation health is equally important. There are several different critical factors that influence vegetation health. This study seeks to understand the trends in biomass at a seasonal and daily scale (using Normalized Difference Vegetation Index, NDVI, as a proxy) and vegetation directional persistence from 2000-2016. Directional persistence is a seasonal NDVI time series based analysis. It is the accumulation of directional change in NDVI by season over time relative to a fixed benchmark. This study also explores trends in precipitation and how they may relate to vegetation across different landscapes. The landscapes studied are: Lower Gorongosa as a whole, a 20 km buffer zone, Mount Gorongosa, and three land cover types within Lower Gorongosa-open savanna, mixed savanna, and closed savanna. The most important findings of this study were that there was a decline in precipitation over this time period, and this decline in precipitation most likely drove the decrease in NDVI. In terms of vegetation persistence, Lower Gorongosa had stronger positive trends than the buffer zone, Mount Gorongosa had higher negative persistence, and directional persistence varied by vegetation type. These are important findings for park managers and conservationists across the world that are using Gorongosa as a model for conservation.