Mozambican woodlands store more carbon than thought: study
Quantum Commodity Intelligence – Mozambique's miombo woodlands could be storing more than twice the amount of carbon originally thought, according to the results of an international research project.
The 3D laser scan study, led by UK carbon ratings agency Sylvera, investigated 500 square kilometres (sq km) of forest and is the first to estimate carbon stocks on a region-wide scale independent of conventional methods that likely underestimate large trees, the company said in a statement.
Researchers collected 450 billion measurements from approximately 8 million trees covering the space to generate estimates of aboveground biomass – the weight of trees above ground.
This showed the carbon stored in these woodlands was 1.5 to 2.2 times more than that predicted by conventional methods, the study concluded.
"Using these 3D laser scanning measurements, we're able to significantly improve the accuracy of our estimates of the biomass and carbon stored in these critical and dynamic miombo woodlands," said co-author Mat Disney of University College London (UCL), in the statement.
Miombo woodlands – named from the Swahili word for Brachystegia, a genus of tree comprising a large number of species – extend across a large region spanning parts of several countries across central and southern Africa.
This area has been reduced from 2.7 million sq km to 1.9 million sq km in the last 40 years due to deforestation, the statement said, adding that the social and environmental implications of this makes "ongoing monitoring essential."
If applied to the rest of Africa's miombo woods, the results of the study indicate traditional methods may have underestimated previous carbon stocks by an amount "nearly equal to the total atmospheric increase in a single year," Sylvera said.
"This implies that governments, business and finance need to do much more to prioritise protecting and restoring these often forgotten forests as a crucial climate change mitigation pathway."
Alongside Sylvera, the study was carried out by researchers from UCL, NERC National Centre for Earth Observation, University of Maryland, University of Edinburgh, Mozambique and the University of Leicester, and in collaboration with and co-financing from the National Fund for Sustainable Development (Mozambique) and the World Bank.
Sylvera has mapped carbon from several forest basins with just a 3% error margin when standard tools provide a 40% error rate, sources close to the company said.
The company uses light detection and ranging (lidar), which can measure tree branches the size of human fingers, a much higher precision level than the typical data used in the sector, however it also requires expensive field trips.
The agency has previously estimated that the carbon forest stock figure in some tropical forest basins is significantly higher, by up to 40%, than currently estimated.
Sources said this "significantly reinforces the case for REDD projects" but it also means that much more CO2 could enter the atmosphere if these forests were to completely disappear.
