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 Global threat to primates concerns us all
19.01.2017 | Deutsches Primatenzentrum GmbH - Leibniz-Institut für Primatenforschung

nachricht Reducing household waste with less energy
18.01.2017 | FIZ Karlsruhe – Leibniz-Institut für Informationsinfrastruktur GmbH

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: Quantum optical sensor for the first time tested in space – with a laser system from Berlin

For the first time ever, a cloud of ultra-cold atoms has been successfully created in space on board of a sounding rocket. The MAIUS mission demonstrates that quantum optical sensors can be operated even in harsh environments like space – a prerequi-site for finding answers to the most challenging questions of fundamental physics and an important innovation driver for everyday applications.

According to Albert Einstein's Equivalence Principle, all bodies are accelerated at the same rate by the Earth's gravity, regardless of their properties. This...

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

Tracking movement of immune cells identifies key first steps in inflammatory arthritis

23.01.2017 | Health and Medicine

Electrocatalysis can advance green transition

23.01.2017 | Physics and Astronomy

New technology for mass-production of complex molded composite components

23.01.2017 | Process Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>