Date on Senior Honors Thesis


Document Type

Senior Honors Thesis

Degree Name



Geography and Geosciences

Degree Program

College of Arts and Sciences

Author's Keywords

Kavango-Zambezi Transfrontier Conservation Area; GIMMS3g; NDVI; vegetative green-up; vegetative trends


In the past century, researchers have observed changes in vegetation productivity and structure in savannas across the world. These changes, caused by shifts in precipitation patterns, fire patterns, soil nutrients, herbivory, and land management decisions, are important to understand because they affect availability of natural resources, which in turn affects the livelihoods of local populations. This study centers on the Kavango-Zambezi Transfrontier Conservation Area (KAZA), a transboundary conservation area that spans five countries in Southern Africa comprised of large areas of protected land. Using the Normalized-Difference Vegetation Index (NDVI), I tested a 35-year remotely-sensed time series for intra- and inter-annual vegetation patterns in KAZA between 1981 and 2015, including analyses for three communities in the region. A Mann- Kendall test for monotonic trends and a Sen’s Slope test were conducted to analyze inter-annual trends for significance and slope of change, respectively. Annual green-up time, the onset of the growing season, was also analyzed for spatial patterns. I found a positive overall trend of greening, as well as spatially clustered patterns of greening and browning across the study region, with sub-study area variation discussed at the community level. Annual growing season onset green-up patterns also varied, appearing to be spatially clustered across the region. The patterns found here have implications for stakeholders at the local and regional levels and will continue to develop as the region continues to face social and environmental changes, thus, continued monitoring is advised.

Lay Summary

I used a satellite-derived data product to analyze trends in vegetation productivity from 1981-2015 in a large area of protected lands in Southern Africa. I analyzed the spatial distribution of trends of greening and browning of vegetation across the study area and discussed the implications of those trends in the context of the local communities who rely on the natural resources of the area. I found that there are diverse trends across the study area, and areas of similar trends tend to be spatially clustered. These trends are likely linked to changes in factors associated with climate change and will likely continue in coming decades, making the continued monitoring of these trends important to understand the effects of climate change on the livelihoods of the inhabitants of Southern Africa.