Heavy breathing plants producing less carbon than feared

Arctic cotton near Ilulissat, West Greenland Arctic cotton near Ilulissat, West Greenland Andrzej Gibasiewicz
23 Mar
2016
When plants respire, they contribute a massive carbon flux to the atmosphere so their response to higher temperatures is a major concern for scientists. However, it’s now thought that increases in plant respiration may not be as high as previously estimated

Worldwide, plants are believed to produce about 60 billion tons of CO2 each year, around six times the amount humans produce through fossil fuel burning. Why? Plants, like animals, need to respire. They take in CO2 from the air for photosynthesis and emit roughly half of that amount during respiration. Like animals, plants also breathe harder as it gets hotter and, until now, there had been fears among scientists that respiration increases exponentially as temperatures climb, outweighing photosynthesis. In other words, plants were exhaling more CO2 than they were inhaling.

‘With this new model, we predict that some ecosystems are releasing a lot less CO2 through leaf respiration than we previously thought,’ says Kevin Griffin, plant physiologist at Columbia University’s Lamont-Doherty Earth Observatory and co-author of a new study on plant responses to global warming.

The study suggests that this effect has its limits and that rates of increased respiration actually slow as temperatures climb. ‘What we thought was a steep curve in some places is actually a little gentler,’ says Griffin. The global study looked at the respiration of 231 plants species from biomes all over the world and found that the biggest change in estimates are in the coldest regions, which have seen the most relative warming. They found that respiration increase was 28 per cent lower than estimated at the North Slopes of Alaska, and 15 per cent lower than estimated in Black Rock Forest, New York.

While the findings can tell us a lot about carbon storage methods in plants, they might not completely rewrite climate models to predict less warming in the future. ‘We now have a better way to estimate one process, but it’s only one process,’ says Griffin. ‘The whole system is quite complicated, and a small change in the balance between one part and another could produce a really big result. That’s the challenge we face when we think about the Earth as a whole.’

Share this story...

Submit to FacebookSubmit to Google PlusSubmit to Twitter

Related items

Leave a comment

ONLY registered members can leave comments and each comment is held pending authorisation before publishing. Please login or register to voice your opinion.

Geographical Week

Get the best of Geographical delivered straight to your inbox every Friday.

Subscribe Today

EDUCATION PARTNERS

Aberystwyth UniversityUniversity of GreenwichThe University of Winchester

TRAVEL PARTNERS

Ponant

Silversea

Travel the Unknown

DOSSIERS

Like longer reads? Try our in-depth dossiers that provide a comprehensive view of each topic

  • Diabetes: The World at Risk
    Diabetes is often thought of as a ‘western’ problem, one linked to the developed world’s overindulgence in fatty foods and chronic lack of physi...
    National Clean Air Day
    For National Clean Air Day, Geographical brings together stories about air pollution and the kind of solutions needed to tackle it ...
    REDD+ or Dead?
    The UN-backed REDD+ (Reducing Emissions from Deforestation and Forest Degradation) scheme, under which developing nations would be paid not to cut dow...
    When the wind blows
    With 1,200 wind turbines due to be built in the UK this year, Mark Rowe explores the continuing controversy surrounding wind power and discusses the e...
    The true cost of meat
    As one of the world’s biggest methane emitters, the meat industry has a lot more to concern itself with than merely dietary issues ...

MORE DOSSIERS

NEVER MISS A STORY - follow Geographical

Want to stay up to date with breaking Geographical stories? Join the thousands following us on Twitter, Facebook and Instagram and stay informed about the world.

More articles in NATURE...

Energy

A short, summer eclipse in America has solar power generators…

Climate

A dramatic increase in dust storms across the western United…

Climate

Geographical’s regular look at the world of climate change. This…

Climate

A study from the Proceedings of the National Academy of…

Wildlife

It’s not just the bees that are disappearing. Insects across…

Oceans

Far beneath the waves, a race is unfolding to claim…

Climate

Compared to other types of carbon sink, seagrass in Kenya…

Geophoto

Who in their right mind wants to shoot with film…

Climate

Geographical’s regular look at the world of climate change. This…

Geophoto

Calling photographers passionate about capturing and sharing great images of…

Climate

Five experts weigh-in on the future of the Paris Agreement…

Oceans

Analysis into a killer whale found dead off the shores…

Geophoto

For the past ten years, the Chartered Institution of Water…

Geophoto

Less than 4,000 tigers remain in the wild, so it…

Oceans

Zafer Kizilkaya has been awarded the 2017 Whitley Gold Award…

Wildlife

John Kahekwa is the founder and general manager of the…

Polar

Recent observations of Arctic flora and fauna indicate major changes…

Oceans

A massive die-off of Australian mangrove forests is being attributed…

Energy

Geographical’s regular look at the world of climate change. This…

Climate

Was last year’s El Niño a practice run for future…