Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Biological soil crusts endangered by global change

26.02.2018

Model calculations predict a decrease of 25 to 40 percent in biological soil crusts through persisting global warming and increasing land use.

Biological soil crusts protect the soil, accelerate the rate of soil formation and contribute to biogeochemical nutrient cycling via fixation of atmospheric carbon (C) and nitrogen (N). Although, visually, they are among the least impressive communities in nature, they form a vital part of natural cycles.


Biological soil crusts form a fundamental part of the vegetation in the semi-desert of South Africa’s Succulent Karoo.

Bettina Weber

Together with international colleagues, scientists from the Max Planck Institute for Chemistry have now created a world map showing the occurrence of biological soil crusts. With the help of this map and predictions on the impact of global change, the scientists conclude that 25 to 40 percent of the world’s soil crusts will have disappeared by 2070. The journal Nature Geosciences reports on the study in its march issue.

“Biological soil crusts (biocrusts) consist of communities of cyanobacteria, algae, lichens and bryophytes. The layers are only few millimeters thick, forming encrustations on the soil surface of drylands, which stabilize the soil and prevent erosion,” explains Bettina Weber, Research Group Leader at the MPI for Chemistry in Mainz. She has been studying these remarkable communities for many years. Together with her colleagues, the biologist evaluated over 500 publications on the topic of biocrusts to create the first global distribution map. They discovered that biological soil crusts currently cover about twelve percent of the Earth’s surface.

Biocrusts are particularly prevalent in desert and savanna areas, such as in southern Africa, Australia, and Asia as well as across the south-western USA. In temperate latitudes across Central Europe, vascular plants such as trees and shrubs are dominant.

“The occurrence of biocrusts mainly depends on the interaction of precipitation, temperature and agricultural land use,” explains Emilio Rodriguez-Caballero, a former postdoc in Bettina Weber’s working group, who is now doing research at the University of Almeria.

To establish the soil crust map, the Spaniard used 18 different environmental parameters, which determine how suitable an area of land is to the growth of biocrusts. The parameters include climatic factors such as temperature and precipitation, soil properties such as mineral content, agricultural use, and the topography of the landscape.

Not only did the researchers create a global map of soil crusts. Based on various future scenarios, they calculated how the soil crust cover is likely to be affected by global change.

Such emission scenarios were developed by the Intergovernmental Panel on Climate Change (IPCC) and indicate how the Earth will change in terms of climate and land use compared to pre-industrial times. They range from the assumption that global warming will remain less than two degrees Celsius thanks to a massive reduction in emissions, to an extreme scenario in which greenhouse gas emissions and land use continue to increase as before. The latter, sometimes called the business-as-usual scenario, predicts that on average the Earth’s surface will warm up by more than four degrees Celsius compared to pre-industrial times.

Global change: more than a quarter of biocrust surfaces are expected to disappear

Regardless of which scenario the Earth is heading for, the predicted decline in biological soil crusts is between 25 and 40 percent. This means that even in the case of moderate global change, the biocrust cover is expected to decrease by one quarter. This decline is caused not only by rising temperatures and altered precipitation patterns but also by agriculture. Bettina Weber’s team expects land use pressure to increase in many semi-arid regions, such as Asia and southern Africa in the coming decades as a result of climate change and a growing world population.

The climate- and landuse-triggered decline in biocrusts could also have a significant impact on biogeochemical cycles such as those of nitrogen and carbon. In earlier studies, Bettina Weber and her colleagues showed that the tiny organisms that make up biocrusts may be responsible for around half of all biological nitrogen fixation that takes place on the Earth’s surface. This is important for the development of ecosystems, as nitrogen is often the limiting nutrient (source: Nature Geoscience, June 3, 2012, DOI: 10.1038 / NGEO1486 and PNAS, DOI: 10.1073 / pnas.1515818112) and improves soil fertility, especially in nutrient-poor ecosystems.

In addition, the large-scale decline in biocrusts would probably also affect our health. “As biocrusts play a key role in soil stabilization, the widespread decline will likely cause a significant increase in exposure to airborne dust and dust storms − with significant effects on human health and the environment,” says Ulrich Pöschl, Director at the Max Planck Institute for Chemistry. From the researchers’ point of view, it is therefore important to consider the occurrence and cover of biological soil crusts in climate and Earth system models.

Weitere Informationen:

http://DOI: 10.1038/s41561-018-0072-1

Anne Reuter | Max-Planck-Institut für Chemie
Further information:
http://www.mpic.de/

More articles from Earth Sciences:

nachricht Upwards with the “bubble shuttle”: How sea floor microbes get involved with methane reduction in the water column
27.05.2020 | Leibniz-Institut für Ostseeforschung Warnemünde

nachricht An international team including scientists from MARUM discovered ongoing and future tropical diversity decline
26.05.2020 | MARUM - Zentrum für Marine Umweltwissenschaften an der Universität Bremen

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Biotechnology: Triggered by light, a novel way to switch on an enzyme

In living cells, enzymes drive biochemical metabolic processes enabling reactions to take place efficiently. It is this very ability which allows them to be used as catalysts in biotechnology, for example to create chemical products such as pharmaceutics. Researchers now identified an enzyme that, when illuminated with blue light, becomes catalytically active and initiates a reaction that was previously unknown in enzymatics. The study was published in "Nature Communications".

Enzymes: they are the central drivers for biochemical metabolic processes in every living cell, enabling reactions to take place efficiently. It is this very...

Im Focus: New double-contrast technique picks up small tumors on MRI

Early detection of tumors is extremely important in treating cancer. A new technique developed by researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from normal tissue. The work is published May 25 in the journal Nature Nanotechnology.

researchers at the University of California, Davis offers a significant advance in using magnetic resonance imaging to pick out even very small tumors from...

Im Focus: I-call - When microimplants communicate with each other / Innovation driver digitization - "Smart Health“

Microelectronics as a key technology enables numerous innovations in the field of intelligent medical technology. The Fraunhofer Institute for Biomedical Engineering IBMT coordinates the BMBF cooperative project "I-call" realizing the first electronic system for ultrasound-based, safe and interference-resistant data transmission between implants in the human body.

When microelectronic systems are used for medical applications, they have to meet high requirements in terms of biocompatibility, reliability, energy...

Im Focus: When predictions of theoretical chemists become reality

Thomas Heine, Professor of Theoretical Chemistry at TU Dresden, together with his team, first predicted a topological 2D polymer in 2019. Only one year later, an international team led by Italian researchers was able to synthesize these materials and experimentally prove their topological properties. For the renowned journal Nature Materials, this was the occasion to invite Thomas Heine to a News and Views article, which was published this week. Under the title "Making 2D Topological Polymers a reality" Prof. Heine describes how his theory became a reality.

Ultrathin materials are extremely interesting as building blocks for next generation nano electronic devices, as it is much easier to make circuits and other...

Im Focus: Rolling into the deep

Scientists took a leukocyte as the blueprint and developed a microrobot that has the size, shape and moving capabilities of a white blood cell. Simulating a blood vessel in a laboratory setting, they succeeded in magnetically navigating the ball-shaped microroller through this dynamic and dense environment. The drug-delivery vehicle withstood the simulated blood flow, pushing the developments in targeted drug delivery a step further: inside the body, there is no better access route to all tissues and organs than the circulatory system. A robot that could actually travel through this finely woven web would revolutionize the minimally-invasive treatment of illnesses.

A team of scientists from the Max Planck Institute for Intelligent Systems (MPI-IS) in Stuttgart invented a tiny microrobot that resembles a white blood cell...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Dresden Nexus Conference 2020: Same Time, Virtual Format, Registration Opened

19.05.2020 | Event News

Aachen Machine Tool Colloquium AWK'21 will take place on June 10 and 11, 2021

07.04.2020 | Event News

International Coral Reef Symposium in Bremen Postponed by a Year

06.04.2020 | Event News

 
Latest News

Black nitrogen: Bayreuth researchers discover new high-pressure material and solve a puzzle of the periodic table

29.05.2020 | Materials Sciences

Argonne researchers create active material out of microscopic spinning particles

29.05.2020 | Materials Sciences

Smart windows that self-illuminate on rainy days

29.05.2020 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>