Growing, maintaining, and protecting tropical rainforests has long been one of the best natural carbon sink methods known to people. They provide a huge CO2 storage potential and help the world reduce man-made emissions.
The Amazon rainforest has been praised for holding up to five years’ worth of human carbon emissions in its trees and soil. However, some forests are better with their carbon capture abilities than others.
A new study has shown that forests that grow on lowlands have larger capabilities for CO2 storage than tropical forests found on mountains such as Mount Kinabalu in Borneo. Tree growth is normally negatively affected on mountains as temperature decreases with increasing elevation. There is also thick fog, wind, and steep slopes that tend to constrain tree height.
Smaller trees that grow slower such as those in mountains are deemed to contain less carbon sequestered from the atmosphere through growth processes. That hypothesis has been reflected in studies of tropical mountains in the Andes and southeast Asia.
Role Of Forests In Climate Change
Forests in Africa have recently surprised researchers with an event that breaks the status quo. According to new research, tropical mountain forests in Africa actually store as much carbon per hectare as forests in African lowlands. This strange event is specific only to the African continent.
The reason for that is because African tropical mountain forests have a greater abundance of larger trees – over 70 cm in diameter, even though they contain fewer trees per hectare than their lowland counterparts. That means they hold more CO2 as the mass is bigger.
Why African tropical mountain forests have a bigger number of larger trees is a puzzle for scientists.
One answer could be elephant populations that reside in many African tropical mountain regions as they eat and destroy smaller tree stems, creating room for others to grow larger. However, the data doesn’t find much difference in tree height between regions with and without elephant populations.
Another explanation is the low frequency of tropical cyclones or active volcanoes in Africa which means trees are not usually destroyed before they grow tall.
Whatever the reason for their carbon capture abilities, they provide a means for accelerating carbon sequestration. Researchers have calculated that the 0.8 million hectares of African tropical forest lost due to deforestation over the past 20 years, has emitted more than 450 million tonnes of carbon dioxide into the Earth’s atmosphere.
The rates of deforestation in the mountains are also higher than the rates in the lowlands. That is weighing immensely on climate change mitigation efforts.
However, the study also points out that the ability of African mountain forests for greater CO2 storage could translate into an opportunity. Greater incentives could be awarded to developing countries for decreasing deforestation which would mean better forest conservation.
If African countries see economic stimulus in better managing forests for climate change mitigation, there will also be a future for those depending on them for survival.