Southern African mountain carbon: lies, lessons and lighthouses

Southern Africa’s mountain grasslands and fynbos ecosystems are increasingly threatened by global afforestation drives. While promoted as climate solutions, these initiatives frequently rest on misleading classifications of grasslands as “deforested,” overlooking their long palaeoecological history and vital role as biodiversity reservoirs and regional water towers. We argue that these misrepresentations constitute lies that risk irreversible damage: alien tree plantations consume more water, increase fire risk, reduce soil carbon stocks, and undermine livelihoods. Drawing on palaeoecological and climatic evidence, we show that Afromontane grasslands are ancient, fire-adapted systems where most carbon resides belowground, making them unsuitable targets for large-scale tree planting. While cautioning against inappropriate afforestation of naturally non-forested systems, we emphasise that conserving and restoring native forests remains critical where they are ecologically appropriate, highlighting the need to consider trade-offs between grassland and forest carbon, water use, and biodiversity. These findings provide lessons for carbon policy: soils and grasslands should be central to nature-based climate solutions, fire management is integral to sustaining carbon stores, and methodological uncertainties in carbon accounting must be addressed. We highlight lighthouse examples—community-based restoration in Gorongosa, carbon-funded rangeland stewardship in South Africa, and protected grasslands in the Drakensberg—that demonstrate how carbon, water, biodiversity, and livelihoods can be conserved together. Finally, we outline ten unanswered research questions grouped under three themes: carbon capacity and stabilisation, land-use and community engagement, and monitoring and methodological advances. Addressing these gaps will strengthen the credibility of soil carbon initiatives and ensure that future climate solutions are grounded in ecological realities, which will improve sustainability of ecosystems and livelihoods.