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Aim: Forest relicts in the mountainous regions of Africa represent one of the most diverse ecosystems on our planet, but the processes that have generated this remarkable diversity are still poorly understood. We estimate divergence times for an endemic, flightless grasshopper family and reconstruct a potential scenario for their colonization of Africa to test the hypothesis that the diversity of these mountain‐top endemics has been generated by multiple fragmentations and reconnections of tropical rain forests in parallel with climatic fluctuations. Location: Sub‐Saharan Africa. Taxon: Lentulidae (Orthoptera). Methods: We inferred the phylogeny of 7 genera and 28 species of the Lentulidae based on COI, 16S and Histone 3 sequences by using a Bayesian approach and we also estimated divergence dates. Based on our molecular phylogeny as well as the available information on the relationship of six additional genera and local occurrence records for 120 lentulid species across Africa, we reconstruct a potential colonization scenario for most species of this group. Results: Our findings indicate that the forest‐bound lentulids of East Africa represent a monophyletic group that originates from South Africa. We show that major splits in the phylogeny of the Lentulidae coincide with three known fragmentation events of the African rain forests (27, 16 and 9 Ma) and that lentulids subsequently diversified rapidly in parallel with the aridification and strong geological activity in East Africa. Main conclusions: Our results corroborate the diversification patterns reported for several endemic African forest‐bound animal taxa at small scales and endemic African plant taxa at larger scales, highlighting the finding that much of the biodiversity presently found in the forest relicts of the Eastern Arc Mountains biodiversity hotspot has been generated by the interplay between humid periods that allowed the spread of forest‐bound lineages across Africa and periods of aridity‐driven isolation of forests and their associated fauna. [ABSTRACT FROM AUTHOR]

Tropical montane forest ecosystems are pivotal for sustaining biodiversity and essential terrestrial ecosystem services, including the provision of high-quality fresh water. Nonetheless, the impact of montane deforestation and climate change on the capacity of forests to deliver ecosystem services is yet to be fully understood. In this study, we offer observational evidence demonstrating the response of air temperature and cloud base height to deforestation in African montane forests over the last two decades. Our findings reveal that approximately 18% (7.4 ± 0.5 million hectares) of Africa's montane forests were lost between 2003 and 2022. This deforestation has led to a notable increase in maximum air temperature (1.37 ± 0.58 °C) and cloud base height (236 ± 87 metres), surpassing shifts attributed solely to climate change. Our results call for urgent attention to montane deforestation, as it poses serious threats to biodiversity, water supply, and ecosystem services in the tropics., (© 2024. The Author(s).)

Tropical forests store 40-50 per cent of terrestrial vegetation carbon 1 . However, spatial variations in aboveground live tree biomass carbon (AGC) stocks remain poorly understood, in particular in tropical montane forests 2 . Owing to climatic and soil changes with increasing elevation 3 , AGC stocks are lower in tropical montane forests compared with lowland forests 2 . Here we assemble and analyse a dataset of structurally intact old-growth forests (AfriMont) spanning 44 montane sites in 12 African countries. We find that montane sites in the AfriMont plot network have a mean AGC stock of 149.4 megagrams of carbon per hectare (95% confidence interval 137.1-164.2), which is comparable to lowland forests in the African Tropical Rainforest Observation Network 4 and about 70 per cent and 32 per cent higher than averages from plot networks in montane 2,5,6 and lowland 7 forests in the Neotropics, respectively. Notably, our results are two-thirds higher than the Intergovernmental Panel on Climate Change default values for these forests in Africa 8 . We find that the low stem density and high abundance of large trees of African lowland forests 4 is mirrored in the montane forests sampled. This carbon store is endangered: we estimate that 0.8 million hectares of old-growth African montane forest have been lost since 2000. We provide country-specific montane forest AGC stock estimates modelled from our plot network to help to guide forest conservation and reforestation interventions. Our findings highlight the need for conserving these biodiverse 9,10 and carbon-rich ecosystems., (© 2021. The Author(s), under exclusive licence to Springer Nature Limited.)

Tropical forests are carbon-dense and highly productive ecosystems. Consequently, they play an important role in the global carbon cycle. In the present study we used an individual-based forest model (FORMIND) to analyze the carbon balances of a tropical forest. The main processes of this model are tree growth, mortality, regeneration, and competition. Model parameters were calibrated using forest inventory data from a tropical forest at Mt. Kilimanjaro. The simulation results showed that the model successfully reproduces important characteristics of tropical forests (aboveground biomass, stem size distribution and leaf area index). The estimated aboveground biomass (385 t/ha) is comparable to biomass values in the Amazon and other tropical forests in Africa. The simulated forest reveals a gross primary production of 24 tcha(-1) yr(-1). Modeling above- and belowground carbon stocks, we analyzed the carbon balance of the investigated tropical forest. The simulated carbon balance of this old-growth forest is zero on average. This study provides an example of how forest models can be used in combination with forest inventory data to investigate forest structure and local carbon balances.