Gradient of vulnerability of Central African forests to climate change and increased human pressure by 2085. Areas in magenta are the most vulnerable to climate change and human pressure. The green areas are the least vulnerable to both phenomena. Blue areas are very vulnerable to climate change and not very vulnerable to human pressure, and vice versa for orange areas. Credit: Maxime Réjou-Méchain et al, Nature (2021)
Protecting and sustainably managing African forests would require a better understanding of their diversity, the environmental drivers of forest composition, and their vulnerability to climatic changes, a study finds. Researchers also predict that the Congo Basin, the world's second-largest rainforest, is particularly vulnerable to climate change, compounded by the impact of high population growth in Africa.
These were findings by a team of researchers led by Maxime Rejou-Mechain, an ecologist at Institut de recherche pour le développement (IRD)France and colleagues from Cameroon, Central African Republic, Democratic Republic of the Congo, Gabon and Republic of the Congo. The researchers used an extensive dataset of forest inventories to model the main floristic and functional gradients over central African forests; and assess their expected vulnerability under forecasted conditions of global climatic and anthropogenic change.
“We compiled the abundance distributions of 193 dominant tree taxa in 185,665 field plots (around 90,000 ha) from commercial forest inventories spread over the five main forested countries in central Africa (Cameroon, Central African Republic, the Democratic Republic of the Congo, Gabon, and the Republic of the Congo,” the study says.
Paolo Cerutti, a senior scientist at the Centre for International Forestry Research (CIFOR) and the International Centre for Research in Agroforestry (ICRAF) says knowledge about the second largest expanse of tropical forest is growing, but it is still scant, and dwarfed by knowledge of other forests. He says there are many reasons for this historical gap, but the collation of such a vast amount of scattered quantitative data being assessed together was a positive development. The information was collected and assessed by co-authors from universities and research institutions of Kinshasa, Yaoundé, Libreville and Bangui, indicating both North-South and South-South collaboration and shared knowledge.
He says this knowledge can support policymakers in their decisions, especially in land-use planning, an exercise that most countries in the Congo basin must perform with poor data and information.
Abubakr Salih Babiker, climate scientist at Intergovernmental Climate Prediction and Application Centre (ICPAC) in Nairobi, says population increase will increase the risk of climate and environmental changes, because it means more demand for energy and natural resources. For example, it will lead to more deforestation to create agricultural land, as experienced in Brazil, and will increase fossil fuel burning for energy supplies.
The accompanying increases in climate stress, human population needs, and resource extraction in central Africa raise environmental concerns. The threats may have considerable impacts on the carbon budget, climate, and biodiversity of central African forests, which shelter some of the world's most beloved wildlife species and which are already experiencing a much drier and seasonal climate than other tropical forests.
Policymakers can use the results of the study to shape transnational conservation and management strategies that aim to provide a sustainable future for central African forests.
