This paper provides information on carbon stock at the habitat level in the above ground biomass (ABG), standing floor litter and soils in a 10 year-old Tectona grandis plantation following restoration of a degraded secondary forest at Obafemi Awolowo University, Ile-Ife Nigeria. Four sample plots 25 m x 25 m, two in Tectona grandis plantation and two in a nearby degraded secondary forest were studied. Soil samples were randomly collected at 0-20 cm and bulk density determined. Standing floor litter was randomly collected at five points every three months for one year, sorted into different litter components. Soil and standing floor litters carbon concentration and C stock were determined. Above ground biomass (ABG) and carbon stock were significantly (p=0.003 and p=0.0001) higher in the plantation, the order is ABG > soil > standing floor leaf litter > standing floor wood litter. Soil C stock varies from 10.47 t ha-1 in the plantation to 10.58 t ha-1 C in the forest. Above ground biomass, standing leaf and wood litter were estimated as 18.26-5.81, 0.49-0.36, 0.06-0.08 t ha-1 C, respectively (plantation to secondary forest). Reforestation after 10 years has increased C stocks by 45% in ABG in the plantations.

Composition and distribution of vascular epiphytes were studied in three different areas at Obafemi Awolowo University estate, Nigeria. Each plot, in the selected area, was used for identification of host and epiphytes. Trees were carefully examined. Presence, positions on the host plants and life-forms of all the epiphytes were recorded. Diameter at breast height of the hosts, bark characteristics and height were determined. The climatic data of the areas were measured to determine the relationship between them and epiphytes distributions. Result showed 41 epiphytes belonging to 14 genera and 11 families were identified. Open area had the highest number of epiphytes ( 22) followed by forest patches ( 14) then secondary forest (five). The epiphytes were not host specific except epiphytic ferns and Ficus vogelii. Diameter at breast height has effect on the epiphytes distribution and composition. The distribution of epiphytes and environmental factors were lowest in the secondary forest. Moraceae was the most dominant host family (44.8%) while Nephrolepis undulata and Nephrolepis biserrata were the most common species of epiphytes. Most epiphytes preferred sub-canopy level, few occurred in the canopy level but none at emergent level. Climatic factors, diameter at breast height and bark characteristics of the host plants are useful in determining compositions and distributions of these epiphytes.

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Nutrient contents in litter and soil were assessed in four 0.06 ha plots of Bambusa vulgaris stands in a secondary rainforest at Ile-Ife, Nigeria, with a view to providing information on nutrient availability that was generally lacking in the forest ecosystem. The collected litter were sorted into leaves and twigs, oven-dried at 70 °C to a constant weight, ground and analysed for nutrients. Leaf litter had higher concentration of Ca, K, Na, P, Mn, Zn and Cu, while C, Mg, Fe and N were higher in twig litter fall fraction. Exchangeable cations, pH, sand content and organic C were significantly lower (p < 0.05), while total N, available P, silt and clay contents were higher in the soil dominated by bamboo stands. Bambusa vulgaris is a better conserver of C, N and P compared to areas dominated by trees and shrubs species in the secondary forest.

The forest land's conversion into tree crops plantations plays a major role in the loss of biodiversity. Therefore, understanding the impacts of land-use change on species diversity is very critical for ecosystem functioning and stability. This study was carried out to evaluate the effect of land-use changes on under storey species diversity in the Theobroma cacao and Citrus sinensis plantations. Two, 25 m × 25 m plots were sampled in each plantation and a nearby undisturbed secondary rainforest for comparison. The diameters (dbh-1.3 m) of all trees at breast height >10 cm were measured in each plot. Five line transect were systematically laid and a quadrat of 50 cm × 50 cm placed at every 1 m point to identify the under storey species (herbaceous, shrubs, tree saplings and climbers) present in each plot. Percentage canopy, species diversity using Shannon-Wiener, Simpson's index and Evenness were determined, while species similarity was determined using the Jaccard's similarity index. Results indicate that woody basal area and stem density in Theobroma cacao were significantly (P<0.05) higher than the Citrus sinensis plantation. A total number of 25, 27, and 14 under storey species distributed in 16, 19 and 11 families were found in Theobroma cacao, Citrus sinensis plantations and secondary forest respectively. Panicum maximum and Axonopus compressus were the dominant grasses in the Theobroma cacao and Citrus sinensis plantations respectively. The percentage canopy cover was significantly (P<0.05) higher in the secondary forest than the plantations. The land use modification has significantly increased the under storey species composition.