Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Savannahs help to slow climate change

22.05.2015

Tropical rainforests have long been considered the Earth’s key ecosystem as they sequester a substantial amount of carbon dioxide from the atmosphere, thereby slowing down the increasing greenhouse effect and climate change.

Researchers from the Max Planck Institute for Biogeo-chemistry in Jena, Germany, participated in a global research project that now shows that semi-arid ecosystems occupying the transition zone between rainforest and desert are as important as rainforests, dominating the ongoing increase in carbon dioxide sequestration by ecosystems globally as well as large fluctuations between wet and dry years.


Savannah landscape in Tansania

Picture: Fritz/Heinrich

Carbon dioxide (CO2) exists naturally in the atmosphere, but it is also the greenhouse gas that is most altered by human activities, most notably fossil fuel combustion and tropical deforestation. The Earth’s vegetation reduces the increase in atmospheric CO2 concentrations by sequestering over a quarter of anthropogenic emissions.

This so-called carbon sink results from the balance between plant photosynthesis, which annually takes up a significant fraction of the CO2 in the atmosphere, and a slightly smaller quantity of CO2 that is released back to the atmosphere through life processes (respiration) and wild fires.

The vegetation’s resultant carbon sink slows down the rate of increase of greenhouse gases in the atmosphere and helps mitigate global climate change, thus providing a vital ecosystem service.

In an international study released in Science this week, researchers from the Max Planck Institute for Biogeochemistry in Jena, Germany, coauthored an international study led by researchers from Lund University in Sweden. They show that semi-arid ecosystems—savannahs and shrublands—play an extremely important role in controlling carbon sinks and the climate-mitigating ecosystem service they represent.

„Forest ecosystems including tropical and other major forest biomes take up most of the CO2 “, says Sönke Zaehle, group leader at the Max Planck Institute for Biogeochemistry. Tropical rainforests are highly productive, taking up a lot of carbon dioxide, but rainforests are crowded places with little room to fit in more plants to do more photosynthesis and to store carbon. In addition, the typical moist, hot weather conditions are ideal for growth and do not change much from year to year.

In savannahs it is different. As productivity increases there is room to fit in more plants whose growing biomass provides a sink, or store, for carbon sequestered from the atmosphere. In addition, savannahs spring to life in wetter years, thus causing large interannual fluctuations in carbon dioxide uptake between wet and dry years. Large enough, the scientists show, to dominate the variability of the carbon dioxide increase in the atmosphere.

“Despite contributing only 20% to the vegetation’s carbon sink, savannahs are the largest controlling factor for year-to-year variations of the terrestrial carbon budget” says Markus Reichstein.

We have long known that we need to protect the rainforests but, with this study, the researchers show that a heightened effort is needed to manage and protect the semi-arid regions of the world as well. They will become even more important in the future as climate variability and extremes increase in a warmer world.

“This study brings out clearly the importance of directing attention towards savannahs and other dry-climate ecosystems that have been largely neglected so far in climate policy discussions, and that moreover characterize the landscapes of some of the poorer countries of the Earth", says Benjamin Smith, Professor of Ecosystem Science at Lund University, Sweden. (aa/ef/sz/mr)

Original publication:
The dominant role of semi-arid ecosystems in the trend and variability of the land CO2 sink
Anders Ahlström, Michael R. Raupach, Guy Schurgers, Benjamin Smith, Almut Arneth, Martin Jung, Markus Reichstein, Josep G. Canadell, Pierre Friedlingstein, Atul K. Jain, Etsushi Kato, Benjamin Poulter, Stephen Sitch, Benjamin D. Stocker, Nicolas Viovy, Ying Ping Wang, Andy Wiltshire, Sönke Zaehle, Ning Zeng.
Science. DOI: 10.1126/science.aaa1668

Weitere Informationen:

https://www.bgc-jena.mpg.de/bgi/index.php/Main/HomePage Department webpage

Dr. Eberhard Fritz | Max-Planck-Institut für Biogeochemie

More articles from Ecology, The Environment and Conservation:

nachricht Dispersal of Fish Eggs by Water Birds – Just a Myth?
19.02.2018 | Universität Basel

nachricht Removing fossil fuel subsidies will not reduce CO2 emissions as much as hoped
08.02.2018 | International Institute for Applied Systems Analysis (IIASA)

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Building a brain, cell by cell: Researchers make a mini neuron network (of two)

23.05.2018 | Life Sciences

One-way roads for spin currents

23.05.2018 | Physics and Astronomy

A simple mechanism could have been decisive for the development of life

23.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>