Sustainability, Population and Structure of Woody Species Composition of Taraba State Forests

Abstract

Sustainability, population and structure of woody species composition of Taraba state forests were studied for future management strategies that allow a more sustainable use of woody species and a better conservation of forest ecosystems. The objectives of the study were to study the woody species dominance, important value index and population structure in different ecological zones of Taraba State forests. Data were obtained through woody species survey and the study area was stratified into three ecological zones and two protected areas. Five plots each measuring 50×50 m were sampled in each protected area and two protected areas were also sampled from each ecological zone. A total of 30 plots and 6 protected areas were sampled and all the woody species that occurred in the plots were also sampled. Data were analyzed using descriptive and inferential statistics such as Tables, percentages, frequency, ANOVA and LSD. A total of 3760 individual woody stands from 60, 34 and 32 species in Montane Forest, Southern and Northern Guinea Savanna respectively were recorded. Strombosia postulate, Pleiocarpa pycnantha, Pericopsis laxiflora, Hymenocardia acida and Ziziphus mauritiana were the dominance species while their corresponding rarest species were Goria sp, Afzelia africana, Elaesis guneensis, Combretum tomentosum and Ficus sur. Strombosia postulate and Pleiocarpa pycnantha were the dominant woody species with high important value indices in Montane forest zone as opposed to Pericopsis laxiflora and Ziziphus mauritiana which dominated the Southern and Northern guinea savanna respectively. The rarest species of Goria sp, Afzelia africana, Elaesis guneensis, Combretum tomentosum and Ficus sur in the study area could be connected to its usefulness as fodder species. The population structure of woody species was found to be very low in the middle diameter classes.The diameter class distribution resembles interrupted “U” shape indicating the removal of merchantable trees. There were no significant differences (p>0.05) among the protected areas and ecological zones due to the low dominance and important value indices. This needs appropriate management techniques to improve forest composition and structure in the study area for sustainability.