Deforestation is driven by agricultural expansion in Ghana’s Forest Reserves

url: https://doi.org/10.1016/j.sciaf.2019.e00146

Summary

Ghana’s protected forest reserves have suffered average annual deforestation rates of 0.7%, 0.5%, 0.4%, and 0.6% for the periods 1990-2000, 2000-2005, 2005-2010 and 2010-2015, respectively. The Ashanti region has recorded the second highest deforestation rates. Despite the government’s efforts to maintain and protect Ghana’s forest reserves, deforestation continues. We observed deforestation patterns in the Ashanti region of Ghana from 1986 to 2015 using Landsat imagery to identify the main causes of deforestation. We obtained and processed two adjacent Landsat images from the United States Geological Survey’s (USGS) National Center for Earth Resources Observation and Science at 30 m spatial resolution for 1986, 2002, and 2015. We then supported the results with findings from 291 farm household surveys in communities fringing the forest reserves. By 2015, dense forest covered 53.3% of the land area of the forest reserves, and the remaining area had been disturbed. Expansion of annual crop farms and tree crops caused 78% of the forest loss within the 29-year period. Afforestation projects are ongoing some of which employ the participation of farmers, yet agricultural expansion exerts more pressure on the remaining dense forest. Agricultural intensification on existing farmlands may reduce farm expansion into the remaining forest areas. Strengthening and enforcing forest protection laws could minimise the extent of agricultural encroachment into forests. Mixed tree-crop systems could reduce the effects of arable farming on deforestation, limit the clearance of trees from farmlands, enhance the provision of ecosystem services, and improve the soil’s fertility and moisture content. A forest transition may be underway leading to more trees in agricultural systems and better protection of residual natural forests.

Status of land cover change in forest reserves for 1986, 2002, and 2015. The upper left figure (A) represents the initial state of the forest reserves as at 1986, the upper right figure (B) shows the change that occurred by the end of the year 2002, and the lower right figure (C) shows the state of the reserves as at 2015.