Analyzing BDq method of selective harvesting in Omo Forest Reserve, Ogun State, Nigeria

Abstract

The Omo Forest Reserve in Ogun State, Nigeria, faces degradation and loss of biodiversity due to unsustainable harvesting practices, prompting the need to investigate the effectiveness of selective harvesting as a sustainable forest management approach for maintaining continuous cover forestry The aim of this study was to assess the effectiveness of selective harvesting in maintaining continuous cover forestry and promoting sustainable forest management in the Omo Forest Reserve. Selective harvesting based on the BDq method was applied. Ten 50 metres x 50 metres (m) temporary sample plots were laid at the study site. Trees with a diameter at breast height (dbh) of at least 10 centimetres (cm) were sampled and measured. Harvesting with the BDq method was quantified, by setting B at 20 m²/ha, 25 m²/ha, and 30 m²/ha for heavy, medium, and light harvesting regimes, respectively. The maximum diameter D was set at 65 cm and the q-ratio was calculated for each sample plot. The heavy, medium, and light regimes produced appropriate felling intensities (FI). For example, a heavy regime in Plot 1 yielded 16.1 trees/ha with a corresponding extracted volume of 9.639 m³/ha (FI: 14.197 %). The medium and light regimes had FI of 5.647 % and 0.351 %, respectively. A heavy regime in Plots 4, 5 and 9 yielded 18.258 m³/ha, 36.559 m³/ha and 66.492 m³/ha, respectively. The three regimes did not produce any timber harvesting on some plots. This study demonstrates the potential of the BDq method for selective harvesting in promoting continuous cover forestry in the Omo Forest Reserve, Nigeria, highlighting the importance of diversified forest structure and genetic diversity in adapting to climate change