Greener Journal of Agronomy, Forestry and Horticulture Vol. 2 (3), pp. 062-072, July 2014.
ISSN: 2354-2306 © 2013 Greener Journals
Manuscript Number: 0523014247
Floristic Patterns and Impact of Edaphic Heterogeneity on Species Assemblages within Woody Forests Layers in Semi-deciduous Forests from the Congo Basin
Amani A. Christian*1, Jean Lejoly2
1Center for International Forestry Research; 25, av. Grevilleas, Goma, D.R.Congo.
2Herbarium de l’Université Libre de Bruxelles, Belgium.
2Email : jlejoly @ ulb.ac .be
*Corresponding Author’s Email: c.amani @ cgiar .org; Tel: +243 9 97 42 33 00
Knowledge of floristic composition and structure of forests is useful in identifying important elements of plant diversity, protecting threatened and economic species. Investigations into floristic composition and structure of forests are essential in understanding the forest ecosystem dynamics and conservation.
Using 1-ha plots established in 3 sites harboring semi-deciduous forests in the Congo Basin, we defined floristic patterns of the vegetation within forest layers. To account for common and rare species, we considered the diversity indices of orders 0, 1 (exponential of the Shannon index) and 2 (inverse of Simpson index). We used the Chao 1 index for diversity of order 0. The jackknife and minimum variance unbiased estimator (MVUE) were considered to estimate diversity of orders 1 and 2. We also assessed the way substrate differentiation affects species assemblages in these forests. Results showed that floristic patterns (species composition and species diversity) vary from a forest layer to another. Three main groups of species assemblages were defined in the overstorey. It has been observed that soil features (clay and sandy substrates) influence species occurrences in these semi-deciduous forests.
Keywords: ecological guild, floristic pattern, plant community, species diversity.