Exploring patterns and gaps in plant diversity of tropical Africa

Using a previously compiled dataset of 600,000 occurrences this study investigates the completeness in knowledge of vascular plants in tropical Africa

Data resources used via GBIF : 70,220 species occurrences
Welwitschia mirabilis
Welwitschia mirabilis observed in Namibe, Angola by Luis Querido. Photo licensed under CC BY-NC 4.0.

In this study, researchers used the RAINBIO database to investigate the main floristic patterns and gaps for tropical Africa. RAINBIO, as previously described, is a compilation of 13 datasets (two of which originated in GBIF), comprising more than 600,000 occurrences across 25,000 vascular plant species.

In their spatial analysis of the dataset they find only 21 half-degree units with more than 100 records. The average number of records per species in a unit is less than two, and more than 4,000 species are only found in a single sampling unit. This degree of endemism is highest in the central African forests with around 30 per cent of species being endemic.

Examining collection efforts through time, the researchers see clear patterns linked to political situations, both globally (e.g. the two world wars) and locally (e.g. Liberian civil wars). National Flora programmes also affect collection efforts. The most well-explored countries according to the dataset are Cameroon and Benin, while the least explored countries include Angola and Somalia.

The authors point to citizen science as a possible means of aiding the filling of gaps in the knowledge of tropical African plant diversity.

Sosef MSM, Dauby G, Blach-Overgaard A, van der Burgt X, Catarino L, Damen T, Deblauwe V, Dessein S, Dransfield J, Droissart V, Duarte MC, Engledow H, Fadeur G, Figueira R, Gereau RE, Hardy OJ, Harris DJ, de Heij J, Janssens S, Klomberg Y, Ley AC, Mackinder BA, Meerts P, van de Poel JL, Sonké B, Stévart T, Stoffelen P, Svenning J-C, Sepulchre P, Zaiss R, Wieringa JJ and Couvreur TLP (2017) Exploring the floristic diversity of tropical Africa. BMC Biology. Springer Nature 15(1). Available at: https://doi.org/10.1186/s12915-017-0356-8.