Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Wallflowers of the Earth system

Algae, lichens, and mosses take up huge amounts of carbon dioxide and nitrogen from the atmosphere and thus also influences the climate

In cities, the presence of algae, lichens, and mosses is not considered desirable and they are often removed from roofs and walls. It is, however, totally unfair to consider these cryptogamic covers, as the flat growths are referred to in scientific terms, just a nuisance.

Lichen on a twig. The photo shows various lichen species that have colonised a twig. Lichens as the common orange lichen (Xanthoria parietina) are a symbiosis of a fungus and green or blue green algae (cyanobacteria). They belong to the cryptogamic covers that can fix carbon dioxide and nitrogen depending on the species. Picture: W. Elbert, MPI for Chemistry

Lichens, like the green-yellow map lichen depicted in this image, are pioneers of life: They grow on rocks, paving the way for other plants. Picture: Uli Pöschl, MPI for Chemistry

Scientists at the Max Planck Institute for Chemistry have discovered that these mostly inconspicuous looking growths take up huge amounts of atmospheric carbon dioxide and nitrogen and fix it at the earth’s surface. Cryptogamic covers are responsible for about half of the naturally occurring nitrogen fixation on land and they take up as much carbon dioxide as is released yearly from biomass burning. These new findings will help to improve global flux calculations and climate models, in which up to now the carbon and nitrogen balance of the cryptogamic covers have been neglected.

The roles that forests and oceans play in the climate and in the global exchange of oxygen, carbon, and nitrogen have been documented in numerous scientific studies. The importance of algae that grow on land, lichens, and mosses for the nitrogen and carbon fluxes and also for the carbon dioxide balance is normally not taken into consideration. This even though cryptogamic covers including the blue green algae (cyanobacteria) cover approximately 30% of soil surface that includes the surfaces of plants. Life forms that get their energy through photosynthesis, but don’t flower, belong to the cryptogams. They are found in all ecosystems, not just on roofs, trees, or walls. Cryptogamic covers, which consist of some of the oldest life forms on our Planet, are also found on cliffs and in soils in dry regions.
“Actually, we wanted to know which compounds the cryptogamic covers emit into the air“, said Wolfgang Elbert, who initiated the research at the Max Planck Institute of Chemistry. “We found that there are a lot of studies about the ecological role of these life forms, but their contribution to the global nitrogen and carbon balance has been neglected until now.“ To get at the importance of the cryptogamic covers, the chemists analysed the data from hundreds of studies in cooperation with biologists and geologists. Their finding: Algae, mosses, and lichens take up approximately 14 billion tons of carbon dioxide and fix approximately 50 million tons of nitrogen per year.

Kryptogamic covers are ecologically important especially as they fix nitrogen

The magnitude of these numbers surprised the Mainz´ researchers and their colleagues at the University of Kaiserslautern and the Biodiversity and Climate Research Centre in Frankfurt because the cryptogamic covers take up about as much carbon dioxide as is annually released by the burning of forests and other biomass.

Especially amazing is the amount of nitrogen that is fixed by the cryptogams and that is thereby made available in the soil and to other organisms. “This represents half of the naturally fixed nitrogen on land, which is of particular importance for ecosystems because nitrogen is often the limiting nutrient. Also, the uptake of CO2 by plants is often limited by the availability of nitrogen“, explained Ulrich Pöschl, leader of the research group.

The results support that crytpogamic covers are an important nitrogen source especially in nutrient-poor ecosystems and dry regions and that they promote the fertility and stability of ground surfaces. (SB/PH)

Original publication
Wolfgang Elbert, Bettina Weber, Susannah Burrows, Jörg Steinkamp, Burkhard Büdel, Meinrat O. Andreae and Ulrich Pöschl
Contribution of cryptogamic covers to the global cycles of carbon and nitrogen
Nature Geoscience, June 3rd 2012; DOI: 10.1038/NGEO1486

Dr. Susanne Benner | Max-Planck-Institut
Further information:

More articles from Life Sciences:

nachricht Signaling Pathways to the Nucleus
19.03.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht In monogamous species, a compatible partner is more important than an ornamented one
19.03.2018 | Max-Planck-Institut für Ornithologie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Tiny implants for cells are functional in vivo

For the first time, an interdisciplinary team from the University of Basel has succeeded in integrating artificial organelles into the cells of live zebrafish embryos. This innovative approach using artificial organelles as cellular implants offers new potential in treating a range of diseases, as the authors report in an article published in Nature Communications.

In the cells of higher organisms, organelles such as the nucleus or mitochondria perform a range of complex functions necessary for life. In the networks of...

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

Im Focus: Surveying the Arctic: Tracking down carbon particles

Researchers embark on aerial campaign over Northeast Greenland

On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...

Im Focus: Unique Insights into the Antarctic Ice Shelf System

Data collected on ocean-ice interactions in the little-researched regions of the far south

The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...

Im Focus: ILA 2018: Laser alternative to hexavalent chromium coating

At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.

When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

Latest News

A new kind of quantum bits in two dimensions

19.03.2018 | Physics and Astronomy

Scientists have a new way to gauge the growth of nanowires

19.03.2018 | Materials Sciences

Virtual reality conference comes to Reutlingen

19.03.2018 | Event News

Science & Research
Overview of more VideoLinks >>>