TEATIME 4 Citizen Scientists!

Tea is buried everywhere. Photo credits Ursula Koch

By: Taru Sandén (Lehtinen), post-doctoral researcher Department for Soil Health and Plant Nutrition at the Austrian Agency for Health and Food Safety (AGES)

This is the 2nd in a two part blog series.


If we want to understand and predict the emissions of carbon dioxide from soils on a global scale, it is crucial to measure decomposition rates. Tea Bag Index (TBI) is a standardised method that was developed to do exactly that! You can read more about this in our previous blog. In short, the measurements need to be done in different types of soils under different kind of land use. Our goal is to make a global map of decomposition. With this map we want to test how TBI is affected by climate change. For a small group of scientists this task is too big to achieve in a timely manner.

To solve this, and to increase soil awareness globally, the Tea Bag Index has teamed up with Citizen Scientists in many different countries. In Sweden, 250 schools were burying tea bags in 2015. The school classes got their information package and scales in the post with guidance on how to carry out their own climate experiment. The teachers were responsible for the activities across Sweden. If and when needed they could always contact Judith Sarneel from Tea Bag Index. She coordinated the study, calculated all the results, and gave feedback to the school classes. And more classes and countries are to follow this and next year!

In the same year (2015) in the UK, Sarah Duddigan, was encouraging UK gardeners to bury tea bags and to celebrate the UN International Year of Soils. She wanted the gardeners to focus on soil health in their home gardens. Approximately 180 gardeners signed up, and in 2016 more and more gardeners are joining to collect data all across the UK.

In Austria, agricultural schools and farmers are taking part in a Citizen Science Award competition in 2016. Taru Sandén (Lehtinen) has asked the Citizen Scientists to bury tea bags in maize fields, grasslands or forests in June and to dig them up again after three months. Tea Bag Index is one of 10 projects participating in the Citizen Science Award, thus, there are possibilities for the Citizen Scientists to participate in more projects at the same time and all the data obtained will be incorporated in the global TBI map.


School children bury teabags. Photo credit Judith Sarneel

Tea Bag Index team members prepare packets for schools.
Photo credit Judith Sarneel


Soils receive very little attention in media coverage of environmental issues. 2015-2024 has been named to International Decade of Soils. The Tea Bag Index hopes that it will also be a Global Decade of the Tea Bag Index! We specifically aim to involve school classes and youth groups as those have shown the highest response and most reliable data so far. We hope to get as many Citizen Scientists as possible involved in the project! Tea Bag Index team would be grateful for your help in spreading the word about this global initiative, and your support in making a global decomposition map reality!

If you are ready for some TEATIME, simply write to tbi@decolab.org and join the fun!