Mbi Crater (Cameroon) illustrates the relations between mountain and lowland forests over the past 15,000 years in western equatorial Africa

Pollen-based vegetation, biodiversity, and biome reconstructions over the last 15,500 years from sediment core data at Mbi Crater in the Cameroon highlands (6.089273 degrees N, 10.348549 degrees E; 2015 m above sea level) are used to discuss the behavior of the lower edge of the Afromontane forest facing climate change. The data reveal that the post-glacial forest change gradually happened at Mbi and that the forest-wooded grassland ecotone was highly influenced by the climate variability related to the North Atlantic. The forest disruption and diversity loss intermittently occurred over the whole period, and their vegetation changes temporally match dry-cold events at the northern latitudes during the Younger Dryas, at 9.5-9.1 ka, 8.6-8.0 ka, 6.7-6.0 ka, 3.2 ka, and during the Little Ice Age (LIA). During the LIA, the mountain forest was subject to unprecedented levels of disturbance at all altitudes, unlike the seasonal lowland forests, which appears to have been only marginally affected.

Automated summary

The behavior of Afromontane forest in response to climate change was examined using pollen-based vegetation, biodiversity, and biome reconstructions from sediment core data at Mbi Crater in the Cameroon highlands. The data showed that forest changes gradually occurred at Mbi, and the ecotone between forest and wooded grassland was strongly influenced by climate variability associated with the North Atlantic. Forest disruption and diversity loss occurred intermittently throughout the period, and these vegetation changes correlated with dry-cold events in northern latitudes. The mountain forest experienced unprecedented disturbance during the Little Ice Age, while the lowland forests were marginally affected.