Tropical Forests
By Dr Arvind Kumar
According to a new study report, publishede recently in Science Daily, it is revealed that as climate change enhances tree growth in tropical forests, the resulting increase in litterfall could stimulate soil micro-organisms leading to a release of stored soil carbon. The research was led by scientists from the Centre for Ecology & Hydrology and the University of Cambridge, UK. The scientists used results from a six-year experiment in a rainforest at the Smithsonian Tropical Research Institute in Panama, Central America, to study how increases in litterfall — dead plant material such as leaves, bark and twigs which fall to the ground — might affect carbon storage in the soil. Their results show that extra litterfall triggers an effect called ‘priming’ where fresh carbon from plant litter provides much-needed energy to micro-organisms, which then stimulates the decomposition of carbon stored in the soil.
According to lead author of the report, Dr Emma Sayer from the UK’s Centre for Ecology & Hydrology, “most estimates of the carbon sequestration capacity of tropical forests are based on measurements of tree growth. Our study demonstrates that interactions between plants and soil can have a massive impact on carbon cycling. Models of climate change must take these feedbacks into account to predict future atmospheric carbon dioxide levels.”
The study concludes that a large proportion of the carbon sequestered by greater tree growth in tropical forests could be lost from the soil. Given the vast land surface area covered by tropical forests and the large amount of carbon stored in the soil, this could affect the global carbon balance.
