By Nneka Nwogwugwu
Scientists studying tropical forests in Africa’s mountains were surprised to uncover how much carbon they store, and how fast some of these forests are being cleared.
The international study reported today in Science Daily on Thursday found that intact tropical mountain (or montane) forests in Africa store around 150 tonnes of carbon per hectare.
This means that keeping a hectare of forest standing saves CO2 emissions equivalent to powering 100 homes with electricity for one year.
The study found that African mountain forests store more carbon per unit area than the Amazon rainforest and are similar in structure to lowland forests in Africa.
Existing guidelines for African mountain forests, which assume 89 tonnes of carbon per hectare, greatly underestimate their role in global climate regulation.
The international team also investigated how much tropical mountain forest had been lost from the African continent in the past 20 years.
They found that 0.8 million hectares have been lost, mostly in the Democratic Republic of the Congo, Uganda and Ethiopia, emitting over 450 million tonnes of CO2 into the atmosphere. If current deforestation rates continue, a further 0.5 million hectares of these forests would be lost by 2030.
Lead author Dr Aida Cuni-Sanchez, from the University of York’s Department of Environment and Geography and at Norwegian University of Life Sciences, said: “The results are surprising because the climate in mountains would be expected to lead to low carbon forests.
“The lower temperatures of mountains and the long periods they are covered by clouds should slow tree growth, while strong winds and steep unstable slopes might limit how big trees can get before they fall over and die,” he said.
