A Test of Enhanced Vegetation Index as an indicator of human–elephant conflict around Bia Conservation Area, Ghana

摘要

Human–elephant conflict (HEC) occurs across Africa and is a major threat to the continued existence of the African elephant. To effectively and efficiently implement mitigation measures, a thorough understanding of the spatial and temporal patterns of HEC is required. This study used a systematic, grid-based geographic information system to analyse the spatial and temporal relations between HEC onset and intensity in 2004 and 2008 and underlying environmental variables in a forest habitat, the Bia Conservation Area, Ghana. Relationships between crop-raiding incident data, Moderate Resolution Imaging Spectroradiometer (MODIS) Enhanced Vegetation Index (EVI) values and remotely sensed derived data were investigated at a 10 km2 scale using principal component analysis and correlation analysis. The onset of crop-raiding in 2004 and 2008 can be attributed to seasonal variation in vegetation biomass. Decreases in EVI values were matched to an increase in crop-raiding incidents. HEC intensity was not significantly related to the environmental variables analysed at the 10 km2 scale. These results suggest that HEC intensity may be influenced by vegetation quality, soil mineral content and/or human density. The methods used in this study could be applied to other forest habitats experiencing HEC for comparative analysis. The influence of vegetation quality, soil mineral content and human density on HEC intensity in forest habitats requires further analysis.