Identification of driving factors of land degradation and deforestation in the Wildlife Reserve of Bontioli (Burkina Faso, West Africa)

Abstract

In Africa, protected areas can play an important role in mitigating the effects of climate change through carbon sequestration but they are threatened due to increasing land degradation and deforestation (LDD). The Total Wildlife Reserve of Bontioli (TWRB) in Burkina Faso is one of the country’s refuges with high biodiversity. This reserve is seriously threatened by human activities, and little information is available about the on-site causes of degradation extent. This study was carried out to investigate drivers and extent of LDD in the TWRB. Household surveys, focus group discussions and field observations were used to identify socio-economic factors that influence land use and land cover (LULC) changes. The socio-economic data were analyzed using rankings and binary logistic regression techniques. Logistic regression model was used to establish the relationship between socio-economic drivers and land cover change. Remote sensing and GIS techniques were used to analyze land use and LULC changes over 29 years, employing Landsat images of 1984, 2001 and 2013. We performed a supervised classification based on the maximum likelihood algorithm to derive vegetation maps. The results revealed significant (p <0.05) LULC change from one class of LULC to another. From 1984 to 2001, tree savannas, bare soils and agricultural lands increased by 17.55%, 18.79% and 21778.79%, respectively, while woodland, gallery forest, shrub savannas and water bodies decreased by 22.02%, 5.03%, 40.08% and 31.2%, respectively. From 2001 to 2013, gallery forests decreased by 14.33%, tree savannas by 22.30% and shrub savannas by 5.14%, while agricultural lands increased by 167.87% and woodlands by 3.21%. LDD occurred at a higher rate in areas bordering the reserve compared to the core-protected area and the inaccessible areas. Agricultural expansion and wood cutting activities were the main direct causes of LDD. Extensive land utilization for agriculture is a major threat to the conservation of biodiversity in this reserve. The research highlighted the soundness of GIS and remote sensing practical application to assess vegetation change extent in Burkina Faso. Understanding the signal extent of vegetation change is particularly important to support efforts by policy makers to halt or at least to slow down the deforestation in the country. There is a need to control the immediate causes of LULC dynamics by limiting agricultural land expansion and wood cutting in the study area.