Scientists hope wetland carbon storage experiment is everyone's cup of tea

Australian scientists have launched a project to bury tens of thousands of teabags in wetlands around the world. They are hoping others will sacrifice a few cups of tea and join in to discover how efficient different wetlands are at capturing and storing carbon dioxide.


Lipton green tea and red tea “rooibos” varieties will be used in the project, which already involves more than 500 scientists in every continent except Antarctica.


Leader of the project, Peter Macreadie from Deakin University’s Blue Carbon Lab, said wetlands were important for carbon capture and storage, a process known as carbon sequestration, holding up to 50 times as much carbon by area as rainforests.


But some wetlands are much better at carbon storage than others, and some are in fact carbon emitters, so they’re not all fantastic,” Macreadie said.


We need to find out the best wetland environments for carbon sequestration so we know where we should invest our energy.”


That’s where scientists have come up against barriers in the past. There are hundreds of thousands of wetlands around the world. A standardised technique for monitoring the carbon is needed for accurate comparison, and monitoring devices can cost thousands of dollars to install.


But Macreadie had been reading scientific research about teabags being buried and used to measure the rate at which carbon was being released from soil into the atmosphere.


Fast decay of the tea inside the bag meant more carbon was being released into the atmosphere, while slower decay meant the soil was holding the carbon.


We’re using the green tea and red tea because they’re made of different components, with green tea degrading more quickly and so we expect it not to last as long, while the red tea is made of tougher components and will break down more slowly,” she said.


If we have these two teas out there in the same environment we can examine how they degrade comparatively to each other and also in comparison to other environments.”


The bags will be monitored over a three-year period and will be dug up and measured at intervals of three months, six months and each year after that.


We also hope that by encouraging professional and citizen scientists to contact us and spread word about this project, other people will begin to understand the importance of wetlands to biodiversity, in carbon sequestration, and in mopping up pollution,” Macreadie said.


The executive director of the Global Carbon Project and scientist with the CSIRO, Pep Canadell, described the initiative as “a great idea”.


“Wetlands are extremely threatened around the world, so anything we can do to highlight their benefits to society will certainly give us more ammunition to convince agencies, and government and non-governmental groups to put resources towards their conservation,” he said.