Research Matters

Research Matters

Ice Age Trees

One researcher is examining trees that grew 20,000 years ago for clues to how modern plants will fare in tomorrow's world of skyrocketing carbon dioxide levels.

Aired March 24, 2008

2 minutes (2.5 MB) | Download mp3


Research into ice age trees shows how plants might respond to skyrocketing carbon dioxide levels. From the University of Kansas, this is Research Matters. I'm Brendan Lynch.

Joy Ward, KU assistant professor of ecology and evolutionary biology, studies trees from 20,000 years ago when low CO2 in the atmposhphere challenged plant life. Ward hopes to show how today's plants might fare in high carbon dioxide concentrations linked to climate change.

Joy Ward: "They are amazing. They can actually take carbon right out of the atmosphere and use it as their food source, whereas on the other hand we as humans have to eat vegetables and meat in order to get carbon sources in our diet."

Ward says ancient air bubbles from ice cores show there was about half as much carbon dioxide in the atmosphere during the last ice age as now. She has found today's plants have severe difficulty thriving under such conditions.

Joy Ward: "So we can actually scrub carbon dioxide out of the atmosphere at very controlled levels to simulate the past. We have found that the average reduction in growth is about 50 percent for plants grown at these ice age carbon dioxide levels. And in fact, for some species, the reduction in growth can be as high as 90 percent and some species completely fail to reproduce."

Ward studies ice age wood and leaves found in the famed La Brea tar pits. She says her research has predictive value for a future with high CO2 levels.

Joy Ward: "There are three types of photosynthetic pathways that plants can use. And we know the majority of plants use the C3 photosynthetic pathway. We know those plants in many cases will be positively benefited by increases in carbon dioxide - if other factors like water and nutrients are very plentiful. If they are not plentiful the positive effects of carbon dioxide are diminished. They also may be diminished in the light of rising temperatures. So there's a double effect there."

For more about ice age trees and carbon dioxide log onto Research Matters dot K-U- dot E-D-U. For the University of Kansas, I'm Brendan Lynch.

Tell Me More

By looking back 20,000 years, KU researcher predicts plant response to rising carbon dioxide levels

We live in a time characterized by skyrocketing amounts of carbon dioxide in our atmosphere. But imagine if you could push a "reverse" button and cut carbon dioxide to lower levels not seen for thousands of years.

Supported by an $869,000 CAREER Award from the National Science Foundation, one University of Kansas researcher is doing just that -- with ice age trees.

Read the full press release