M.S. Jeminiwa’s scientific contributions

The Assessment of forest species composition and species diversity is essential in understanding the status of tree population and diversity for conservation purpose. Olokemeji forest reserve is situated in the lowland rain forest of south-western Nigeria and it occupies a total land area of 58.88 km2 . Six study plots of 50m2 each were randomly selected and designated as Frequently Burnt Plot 1, Frequently Burnt Plot 2, Harvested Plot, Unharvested Unburnt Plot, Arable Plot 1 and Arable Plot 2 for the purpose of assessment of species diversity and distribution of woody species. Seven species of trees were identified belonging to five families. One hundred and eighty two stands were enumerated, with Unharvested Unburnt Plot having the highest number of trees at 50. The dominance index for the woody flora was 1 in Frequently Burnt Plot 1 and 2 as well as Arable Plot 1 and 2 except for the Harvested Plot that had the lowest (0.29) while the Unharvested Unburnt Plot had 0.75. Highest species richness was recorded at the Harvested Plot at 0.71. The species diversity in Harvested Plot was low (1.54), while it was extremely low in Unharvested Unburnt Plot (0.43). Evenness index was lowest in the Unharvested Unburnt Plot at 0.43. Tectona grandis had the highest relative importance value in the Frequently Burnt Plot 1. The low species richness and species diversity is a direct indication of anthropogenic interference in the study plots and the forest reserve; this requires urgent mitigation to prevent a total loss of its structure and function as expected of a forest reserve. Keywords: Species, Diversity, Evenness, Anthropogenic, Forest, Dynamics

Forest degradation has become a major concern in many countries around the world as it has become one of the most debilitating land use crisis in tropical ecosystems. Hence, this study assessed the forest degradation indices in Mokwa forest reserve. Data were collected using structured questionnaires and field reconnaissance survey. Five settlements were selected in and around the forest reserve namely Mokwa, Jangi, Epa, Kpataki and Tswanle. Data were analyzed using descriptive and inferential statistics. Results showed that farming (41.7%) was the main occupation of the people, artisan works (18.8%) and studentship had the least (4.2%). Briquetting of charcoal (20.8%) was the highest causes of forest degradation; commercial farming (18.8%), overgrazing (16.7%) and population increase was the least (4.2%).Global warming (22.9%) was the major effect ofdegradation in the study area, soil erosion (20.8%) and the least was low rainfall (9.4%). Agroforestry practices (27.1%) were recorded as the main mitigation measure for reducing degradation in the area. This was followed by Afforestation and enrichment planting (22.9%), tree planting campaign (18.8%) and the least was forest conservation and management (6.3%). The stepwise multiple regression analysis of the causes with other variables showed that briquetting of charcoal had the highest R2 (0.88), followed by commercial farming R2 (0.84), while population increase had the least R2 (0.57). Nevertheless, sustainable empowerment programs are recommended to boost the livelihood of the rural populace and to reduce the overdependence of the people on the forest reserve. Keywords: forest degradation, enrichment planting, livelihood, briquetting.

Tropical rainforest is continuously threatened by timber exploitation and conversion to other land uses. In this study, tree species diversity and forest structure of Eda Forest Reserve in Ekiti State, Nigeria, were assessed using systematic line transect and purposive sampling techniques for plot demarcation and data collection. Two transects (2000m long) were laid in secondary forest and encroached farmland in the reserve, while the primary forest fragments were sampled purposively. Twenty sample plots (20m×20m) were laid out on each of the vegetation types. All trees >10cm diameter at breast height (dbh) were identified to species level and enumerated for total height and dbh. Data were analyzed using descriptive statistics such as tables, charts, frequency, percentages and diversity index analysis using paleontological statistics software (PAST 2.14). There were 60 species from 22 families, with Sterculiaceae, Caesalpiniaceae and Moraceae being the most abundant families. Individual tree populations were 380 trees/ha, 280 trees/ha and 137 trees/ha in the primary forest, secondary forest and encroached farmland, respectively. Species composition comprised 39, 38 and 19 species in primary forest, secondary forest and encroached farmland,