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Spatial data on vegetation dynamics are sparse for the Djerid oases of Tunisia, but such data are urgently needed by policy makers for natural resource management purposes. These data can be collected by remote sensing and analyzed using Geographic Information System software. We analyzed the changing dynamics of the Tozeur oases in southwestern Tunisia using normalized difference vegetation index (NDVI) index data that were generated from SPOT-5 (Take5) satellite imagery taken from April to September, 2015. We used agglomerative hierarchical clustering (AHC) to produce a dendrogram that segmented the area into similar NDVI classes, then analyzed these clusters with reference to ground-truth data collected by field surveys. The unsupervised classification map produced by AHC represents a spatial model of the NDVI distribution in the oases. The results revealed seven different clusters with very high spatial heterogeneity that were linked to biophysical parameters in the field. (c) 2018 Society of Photo-Optical Instrumentation Engineers (SPIE)