Elephant-induced thicket degradation in the Addo Elephant National Park (AENP), Eastern Cape, South Africa, was assessed during 1973 and 2010 using multitemporal satellite imagery. Changes in the thicket condition, in relation to the AENP expansion, were analyzed using the Normalized Difference Vegetation Index, postclassification, and landscape metrics. The change detection of land-cover classes was analyzed by postclassification. Landscape-spatial metrics were used in order to gain an understanding of vegetation-fragmentation trends. Temporal changes in vegetation gradients in relation to water points and thicket conditions within the botanical reserves were also assessed. The thicket condition was noted to have deteriorated, as the AENP had expanded. An expansion of degraded vegetation away from the water points was identified during the study period. The thicket condition in botanical reserve 1 had fluctuated, whereas it remained constant in reserves 2 and 3. Landscape spatial-metric analyses revealed evidence of increased vegetation fragmentation, as new areas of the AENP had been opened for elephant activity. A progressive decline in intact thicket and an increase in degraded thicket were observed. Remote-sensing techniques can assist with thicket-clump restoration by applying “target monitoring” for the timeous identification of potential-degradation hotspots.
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The Society for Range Management is the professional scientific society and conservation organization whose members are concerned with studying, conserving, managing and sustaining the varied resources of the rangelands which comprise nearly half the land in the world. Established in 1948, SRM has over 4,000 members in 48 countries, including many developing nations.
SRM’s members are land managers, scientists, educators, students, producers and conservationists–a diverse membership guided by a professional code of ethics and unified by a strong land ethic.