A silvicultural approach to volume yield, biodiversity and soil fertility restoration of degraded natural forest in South-West Nigeria

Abstract

The contributions of a silvicultural practice (enrichment planting technique) to ecosystem restoration, management and biodiversity conservation were assessed. Data were collected from eight 25 × 25 m plots located in the three forest types (Degraded Forest, Strict Nature Reserve and Enrichment Planting Forest) in Akure Forest Reserve, Nigeria, using a systematic line transect. Soil samples were also collected in each plot at three depths. The results indicated that there were 51 tropical hardwood species distributed into 24 families in the forest ecosystem. The Shannon–Weiner indices varied from 3.25 to 2.74. Enrichment Planting Forest was discovered to have the highest number of species, genera and families when compared to the other forest types. Also, highest biodiversity indices were obtained for it. All the variables were significantly higher (p < 0.05) in the forest regenerated through enrichment planting. There was generally no significant difference in soil properties among the forest types except for total nitrogen at depths of 30–45 and 45–60 cm for SNR. The enrichment planting silvicultural practice therefore possesses the potential for soil fertility improvement, volume yield increment and restoration of degraded forests. Its use is therefore recommended for forest restoration in developing countries where anthropogenic activities have adversely affected the natural forest ecosystem.