Quantcast
Environmental News for a Healthier Planet and Life

Forests Show Adaptations to Climate Change

Climate
Forests Show Adaptations to Climate Change

Climate News Network

By Tim Radford

Trees may be getting more efficient in the way they manage water. They could be exploiting the higher levels of carbon dioxide in the atmosphere, growing foliage from a lower uptake of groundwater. If so, then the carbon dioxide fertilization effect—predicted by theorists and observed in laboratory experiments—could be real.

Some forests, as they soak up carbon dioxide, are using water more efficiently.

This is a provisional finding, because it is pretty difficult to measure the precise economy of a whole forest or an open wilderness.

But Trevor Keenan—of Macquarie University in Australia and Harvard University in the U.S.—and colleagues report in Nature that they used an indirect measure, called the eddy-covariance technique, to monitor the way managed forests handle two important gases: carbon dioxide and water vapor.

Carbon dioxide levels in the atmosphere were once 280 parts per million; they are now 400 ppm and still rising. For more than 20 years, rigs have towered above the world’s forests recording eddy-covariance, measuring carbon uptake and water-use over areas of a square kilometer.

Keenan and his fellow-researchers looked at the data from 21 temperate and boreal forests in the northern hemisphere and found a remarkably consistent trend: As the years rolled by, and carbon dioxide levels rose, forests used water more efficiently and this was true for all 21 sites.

This so-called fertilization effect has been independently confirmed in arid zones, again by indirect research, through the work of an Australian team studying satellite data, and also seems consistent with a finding reported in Nature Climate Change that tropical forest trees are now producing more flowers, even though the observed temperature rises in the tropics have so far only been modest.

The implication of the most recent research from the boreal and temperate forests is that plants could be partially closing their stomata to keep their carbon levels at a constant level. This finding, like much in science, raises as many questions as it answers. How plants “know” what to do in such circumstances, and how they do it, is still a mystery.

Plants exploit atmospheric carbon dioxide so it should be no surprise that a better supply leads to more efficient growth. But more carbon dioxide also means higher temperatures, more evaporation, more precipitation and more cloud cover—so it has been difficult to observe the impact.

Whether this will turn out in the long run to be a positive feedback that could, to some slight extent, slow global warming is uncertain.

Plants are also sensitive to extreme heat and drought, two other unwelcome companions of climate change due to human emissions of greenhouse gases such as carbon dioxide, so it is too soon to suggest that forests will emerge as the winners.

Other scientists still have to confirm the effect, and measure its scale more accurately. But the latest research does suggest trees are responding to change.

“Our analysis suggests that rising atmospheric carbon dioxide is having a direct and unexpectedly strong influence on ecosystem processes and biosphere-atmosphere interactions in temperate and boreal forests,” says one of the authors, Dave Hollinger of the U.S. Forest Service.

Visit EcoWatch’s CLIMATE CHANGE page for more related news on this topic.

——–

By Michael Svoboda

For April's bookshelf we take a cue from Earth Day and step back to look at the bigger picture. It wasn't climate change that motivated people to attend the teach-ins and protests that marked that first observance in 1970; it was pollution, the destruction of wild lands and habitats, and the consequent deaths of species.

Read More Show Less
EcoWatch Daily Newsletter
An Amazon.com Inc. worker walks past a row of vans outside a distribution facility on Feb. 2, 2021 in Hawthorne, California. PATRICK T. FALLON / AFP via Getty Images

Over the past year, Amazon has significantly expanded its warehouses in Southern California, employing residents in communities that have suffered from high unemployment rates, The Guardian reports. But a new report shows the negative environmental impacts of the boom, highlighting its impact on low-income communities of color across Southern California.

Read More Show Less
Trending
Xiulin Ruan, a Purdue University professor of mechanical engineering, holds up his lab's sample of the whitest paint on record. Purdue University / Jared Pike

Scientists at the University of Purdue have developed the whitest and coolest paint on record.

Read More Show Less

Less than three years after California governor Jerry Brown said the state would launch "our own damn satellite" to track pollution in the face of the Trump administration's climate denial, California, NASA, and a constellation of private companies, nonprofits, and foundations are teaming up to do just that.

Read More Show Less
The Biden administration needs to act quickly to reduce carbon emissions. Andrew Merry / Getty Images

By Jeff Goodell

The Earth's climate has always been a work in progress. In the 4.5 billion years the planet has been spinning around the sun, ice ages have come and gone, interrupted by epochs of intense heat. The highest mountain range in Texas was once an underwater reef. Camels wandered in evergreen forests in the Arctic. Then a few million years later, 400 feet of ice formed over what is now New York City. But amid this geologic mayhem, humans have gotten lucky. For the past 10,000 years, virtually the entire stretch of human civilization, people have lived in what scientists call "a Goldilocks climate" — not too hot, not too cold, just right.

Read More Show Less