Long-Term Impacts of Selective Logging in a Tropical Rainforest in the East Region of Cameroon

Abstract

Although selective logging has become the primary cause of degradation in many African countries, little is known about its long-term effects. This study investigated the long-term effects of selective logging on forest tree species diversity and dynamics in the East Region of Cameroon. Six permanent monitoring plots of 1 ha each in unlogged and logged forests were established in 2005 and a recensus in 2011. Each 1 ha plot was divided into 25, 20 × 20 m quadrats. Each 20 × 20 m quadrat was further divided into 16, 5 × 5 m subquadrats, where the diameter at breast height (DBH) of all trees ≥ 2 cm was measured. There was a decrease in plant species density and richness in all forest types. Sloetiopsis usambarensis was the most important species in the unlogged forests and forests logged 21 years ago. The most important family was Putrangivaceae, Euphorbiaceae and Violaceae in the unlogged forests and forests logged 11 and 21 years ago, respectively. The frequency distribution of stem size classes indicated a reversed J-shape of tropical forests. The above ground biomass (AGB) recovered more than 50% in all forests, and the unlogged forest had the highest AGB (961.8 Mg/ha). Larger stems indicated a forest at a stage of recovery from disturbance. Silvicultural management should be considered.