Trees, ferns, lianas, and palms in the mist in a tropical rainforest in Costa Rica. (Photo credit: Peter Groenendijk)

Trees, ferns, lianas, and palms in the mist in a tropical rainforest in Costa Rica. (Photo credit: Peter Groenendijk)

The assumption that increased atmospheric CO2 levels contribute to increased tree growth is being called into question by this study published in Nature Geoscience. Predicting the response of tropical forests is important in the modeling of future climate scenarios.

Extra CO2 in the atmosphere is expected to increase tree growth, by improving the trees rate of photosynthesis and efficiency of water use. However when researchers looked at the growth rings of over 1,000 tropical trees they saw no evidence that atmospheric CO2 levels lead to any extra growth.

Original research paper published in Nature Geoscience on December 15, 2014.

Names and affiliations of selected authors

Peter van der Sleen, Wageningen University, Netherlands

Pieter Zuidema, Wageningen University, Netherlands