Planting Secrets

Trees in a forest

Plants and climate change: a love-hate relationship!

This is Sandra Tsing Loh with the Loh Down on Science.

Carbon dioxide, or CO2, is a major contributor to climate change. But it’s also a plant food source. When the sun shines, plants turn CO2 into food! So, back when there were more trees on the planet, was there LESS CO2?

Tammo Reichgelt from University of Connecticut and his international team investigated. They went to Foulden Marr, a dry lake in New Zealand. Millions of years ago, it was a large green forest. Now the leaves from that forest are hiding under the lake bed!

The researchers’ idea? Dig ’em up and set ‘em on FIRE! Burning leaves releases the CO2 stored inside them. Then a computer model calculates how much of it was present when the leaves were alive!

Results? There was MORE CO2 in the old forest than today! The scientists believe the CO2 level naturally dropped over time. And so the forest turned into a grassland. And eventually a lake!

Hey – which could be the home of a new family-friendly attraction called…Jurassic Park!

Reichgelt, T., D’Andrea, W. J., Valdivia-McCarthy, A. C., Fox, B. R. S., Bannister, J. M., Conran, J. G., Lee, W. G., & Lee, D. E. (2020). Elevated CO2, increased leaf-level productivity, and water-use efficiency during the early Miocene. Climate of the Past, 16(4), 1509–1521.