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 Bioinvasion on the rise
15.02.2017 | Universität Konstanz

nachricht Litter Levels in the Depths of the Arctic are On the Rise
10.02.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

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: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Organ-on-a-chip mimics heart's biomechanical properties

23.02.2017 | Health and Medicine

Light-driven reaction converts carbon dioxide into fuel

23.02.2017 | Life Sciences

Oil and gas wastewater spills alter microbes in West Virginia waters

23.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>