diversity Article Afromontane Forest Diversity and the Role of Grassland-Forest Transition in Tree Species Distribution Iveren Abiem 1,2,3,* , Gabriel Arellano 4,5 , David Kenfack 5 and Hazel Chapman 1,3 1 School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand;
[email protected] 2 Department of Plant Science and Biotechnology, University of Jos, P.M.B. 2084, Jos 930001, Nigeria 3 Nigerian Montane Forest Project, Yelwa Village 663102, Taraba State, Nigeria 4 Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA;
[email protected] 5 Forest Global Earth Observatory, Smithsonian Tropical Research Institute, Washington, DC 20036, USA;
[email protected] * Correspondence:
[email protected]; Tel.: +234-70-3165-9327 Received: 7 November 2019; Accepted: 7 January 2020; Published: 15 January 2020 Abstract: Local factors can play an important role in defining tree species distributions in species rich tropical forests. To what extent the same applies to relatively small, species poor West African montane forests is unknown. Here, forests survive in a grassland matrix and fire has played a key role in their spatial and temporal dynamics since the Miocene. To what extent these dynamics influence local species distributions, as compared with other environmental variables such as altitude and moisture remain unknown. Here, we use data from the 20.28 ha montane forest plot in Ngel Nyaki Forest Reserve, South-East Nigeria to explore these questions. The plot features a gradient from grassland to core forest, with significant edges. Within the plot, we determined tree stand structure and species diversity and identified all trees 1 cm in diameter.