A research team, including PhD student Carola Martens, from Senckenberg and South Africa’s Stellenbosch University, has investigated how climate change could pose a threat to Africa’s biodiversity.
In this study, scientists demonstrate where these environmental impacts may coincide with population growth and land-use changes. According to their simulations, biodiversity in almost all protected areas will be threatened by at least one of these factors by the end of the 21st century.
This study was recently published in the journal Conservation Biology.
The importance of protecting Africa’s biodiversity
African elephants, white rhinoceros, leopards, Cape buffalos, and lions – also known as the ‘big five’ – are symbolic of Africa’s unique wildlife. “Africa’s protected areas harbour far greater biodiversity than just these five iconic animals. They are the last strongholds of the continent’s unique biodiversity,” explained Carola Martens, from Senckenberg’s Biodiversity and Climate Research Centre and Goethe University, Frankfurt. “However, this diversity is threatened by climate change, population growth, and future land-use changes.”
Martens and her colleagues Professor Dr Thomas Hickler from Senckenberg’s Biodiversity and Climate Research Centre (SBiK-F), Dr Simon Scheiter SBiK-F, and Professor Dr Guy F. Midgley from Stellenbosch University have studied the threat to Africa’s biodiversity, including future impacts of climate change in Africa’s protected areas, incorporating population density and land utilisation, for two scenarios up to the end of the 21st century.
Their modelling study intends to demonstrate where the three factors will be important in the coming decades and where they may interact, which researchers expect will support meaningful conservation planning.
“Climate change is increasingly threatening biodiversity as vegetation zones and habitats change for many species. In addition, the growing world population combined with globally rising living standards requires more and more land for food production, to meet the rising demand for meat, and for bioenergy. We can only halt biodiversity loss if we understand the interactions between climate change, population growth, and land use,” noted Martens.
Conducting simulations from the adaptive dynamic global vegetation model
The simulations were conducted utilising the adaptive dynamic global vegetation model (ADGVM) for two scenarios: The ‘middle-of-the-road’ scenario, where in which current societal developments continue and some climate change mitigation measures are adopted, and the ‘fossil-fuelled development’ scenario.
In the latter scenario, social and economic development is based on the increased exploitation of fossil fuel resources with a high coal content and an energy-intensive lifestyle worldwide. Additionally, the researchers analysed global scenarios for the development of the human population and of land utilisation.
“The results demonstrate that in both scenarios, tree cover generally increases in today’s grasslands and savannas in Africa. For protected areas in West Africa, our analyses revealed climate-induced vegetation change combined with high future population and land-use pressures,” said Martens.
“Only for North Africa, we expect that a large share of protected areas to be without vegetation changes in combination with decreased pressure from population and land use – generally, the pressure on protected areas is therefore increasing.”
According to the study, the ‘fossil-fuelled development’ scenario resulted in greater climate-induced changes in tree cover and higher land-use pressure at the continental scale, while the ‘middle-of-the-road’ scenario was characterised by higher future population pressure.
The future threat to protected areas
“Our work demonstrates that in the future, almost all protected areas are threatened by at least one factor: climate change leading to major vegetation changes, a large increase in the population around the protected area, or growing land-use pressure. The biodiversity of protected areas in West Africa may be particularly affected by this – facing a combination of strong climate change impacts, population growth, and land-use changes,” concluded Martens.
“A sound understanding of individual socio-economic and ecological conditions, as well as of existing or potential future conflicts, is an important basis for the planning of protected areas. Conservation and protection strategies require to be regionally and locally adapted. This can contribute to the protection of the unique diversity of Africa’s ecosystems!”