Article

Floristic Structure of Fire Experimental Plots of Olokemeji Forest Reserve, Ogun State, Nigeria

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Abstract

Total enumeration of tree species was carried out fire experimental plot of Olokemeji forest reserve for relative importance value (RIV) mean heights, mean diameter at breast height and mean basal area. Three investigative plot (Plot A, B and C) were established. Plot A which represents Early Burn is burnt annually during the dry season while Plot B was burnt annually during the rainy season when the trees are still wet and Plot C serves as the protected area. Gmelina arborea had the highest relative importance value (28.31), this is followed by Dalbergia sissoo which had RIV of 10.94. Plot C recorded the highest frequency of trees with the highest tree heights, this is closely followed by Plot A and Plot B being the plot with the lowest mean height. Plot C has the highest mean diameter at breast height (DBH) of trees and it is followed by Plot B and Plot A with very close mean DBH. The highest mean basal area was also recorded in Plot C, the highest total basal area and tree volume was also recorded at Plot C as 32.2 m2 ha-1 and 188.8 m3. The size distribution of tree species depicts that Plot C has been protected just as expected Keywords: Forest, Structure, Flora, Dynamics, Fire

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... In fact, this value can be used to identify the most valuable and useful species for a cluster or an area (Whitney et al., 2018). A number of different methods can be used to determine the importance value of species according to different studies (Razavi et al., 2012;Olorunmaiye et al., 2013;Taiwo et al., 2020). However, for the current study, relative importance value (RIV) was calculated as in Eq. 5, using the relative frequency (RF) and relative dominance (RD' Eqn. ...
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