Historical climate important for soil responses to future climate change

November 30, 2018, Lund University
Photos shows the long-term drought experiment in the Netherlands from where the soils were sampled. A rain curtain has excluded precipitation from entering the soil during the summer for 18 years, simulating the drought. (Photo: Evy de Nijs

Researchers at Lund University in Sweden, in collaboration with colleagues from the University of Amsterdam, examined how 18 years of drought affect the billions of vital bacteria that are hidden in the soil beneath our feet. The results show that this type of extreme weather determines how soils respond to future climate change.

According to the study, microorganisms that have been subjected to long-term drought find it easier than other microbes to recover when moisture in the soil increases again.

"Our results show that the historical climate will affect how microorganisms respond and contribute to climate change in the future. Bacteria adapted to drought could slow the rate of carbon loss from soils," explains Lettice Hicks, biologist at Lund University.

In the study, she and her colleagues examined soil that had been subjected to long-term drought – in this case 18 years of experimental summer drought. The aim was to study how the microorganisms cope and how they recover.

When the soil is moist, the bacteria are active, breaking down . This process provides for plants, and, while a proportion of the carbon from is stored in the soil as bacterial tissue, some is released into the air as .

Photos shows the long-term drought experiment in the Netherlands from where the soils were sampled. A rain curtain has excluded precipitation from entering the soil during the summer for 18 years, simulating the drought. (Photo: Evy de Nijs

During drought, however, the bacteria stop growing and no longer perform their important task in the ecosystem. When rain eventually falls and the soil regains moisture, the bacteria begin to work again. The result is an immediate increase in emissions of carbon dioxide into the air, but as the bacteria recover very quickly, the fraction of carbon released from the soil decreases.

"The carbon balance is affected, as the growth of bacteria keeps carbon in the soil. These findings suggest that microbial communities can adapt to changing , and this might slow the rate of carbon loss from soils," concludes Lettice Hicks.

Explore further: Tibetan soil enrichment with nitrogen and phosphorus leads to carbon loss

More information: Evy A. de Nijs et al. Soil microbial moisture dependences and responses to drying-rewetting: the legacy of 18 years drought, Global Change Biology (2018). DOI: 10.1111/gcb.14508

Related Stories

New research unravels the mysteries of deep soil carbon

September 11, 2018

Energy-starved microbes may be the force that causes huge amounts of carbon to be stored in deep soils, according to a Dartmouth College study. The research finds that less food energy at depth makes it more difficult to ...

Fungi respire millennium-old carbon from Antarctic soil

May 30, 2018

Fungi in Antarctic soils release carbon, as carbon dioxide, that is more than a thousand years old, a team led by scientists at the British Antarctic Survey (BAS) has found. This discovery sheds light on how carbon is released ...

Recommended for you

The long dry: global water supplies are shrinking

December 13, 2018

A global study has found a paradox: our water supplies are shrinking at the same time as climate change is generating more intense rain. And the culprit is the drying of soils, say researchers, pointing to a world where drought-like ...

Death near the shoreline, not life on land

December 13, 2018

Our understanding of when the very first animals started living on land is helped by identifying trace fossils—the tracks and trails left by ancient animals—in sedimentary rocks that were deposited on the continents.

New climate model to be built from the ground up

December 13, 2018

Facing the certainty of a changing climate coupled with the uncertainty that remains in predictions of how it will change, scientists and engineers from across the country are teaming up to build a new type of climate model ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.