Seed Bank Dynamics and Regeneration in a Secondary Lowland Rainforest in Nigeria
Seed bank dynamics and forest regeneration in a secondary lowland rainforest in Nigeria were studied with a view to determine the potential contribution of the soil seed bank to the regeneration of the forest. Six 25 x 25m plots were used and in each plot, ten replicates top soil 0-15cm were collected in March, June and October. The soil samples were subjected to seedling emergence for 20 months to determine density and species composition of the seed banks of the study plots. The results showed that there were more individuals in plot C (a disturbed plot) and herbaceous species dominated (more than 96%) the seed bank of all the study plots and across the seasons. Few woody species emerged in all the plots and there was significant difference (p < 0.05) in density both between the plots and months. Similarity between seed bank and vegetation composition, no matter the forest state, is very low. The most frequent species in the vegetation are absent in the seed bank and vice versa. The seed bank is mainly composed of early successional species and seeds of primary forests are rare in the soil. The few woody species recorded indicate that the soil seed bank may not be an important conservation tool for the regeneration of the degraded forest, therefore reforestation is recommended for restoration of the degraded forest.