Rainforest mushrooms as weather makers

With the help of HZB’s x-ray microscope, MAXYMUS, MPIC<br />scientists in Mainz, Germany, recently decoded the methods<br />used by mushrooms and plants to influence Amazon rainforest<br />cloud formation. Organic substances condense on mushroom and<br />plant derived potassium salts resulting in production of<br />aerosol particles. On these, fog droplets form.<br />

With the help of HZB’s x-ray microscope, MAXYMUS, MPIC
scientists in Mainz, Germany, recently decoded the methods
used by mushrooms and plants to influence Amazon rainforest
cloud formation. Organic substances condense on mushroom and
plant derived potassium salts resulting in production of
aerosol particles. On these, fog droplets form.
© Christopher Pöhlker / MPI für Chemie

Whereas in urban areas, soot or dust particles often double as condensation nuclei, in rain-forests, it is mainly organic evaporations from plants, which periodically trigger fog or cloud formation. Now, at HZB’s BESSY II, Max Planck Institute for Chemistry scientists have shown that inorganic salts also play a role in the process. It appears that tiny potas-sium salt particles make up the core of cloud condensation nuclei in the rainforest. These kinds of salts are evaporated by mushrooms and plants as a way of influencing the number of condensation nuclei and, by extension, affecting cloud formation and precipitation over the rainforest.

Christopher Pöhlker, a Ph.D. student in Dr. Ulrich Pöschl’s and Prof. Dr. Meinrat O. Andreae’s lab at the Max Planck Institute for Chemistry, recently made the discovery using a new aerosol analytical method at HZB’s BESSY II x-ray microscope, MAXYMUS, and at the Lawrence Berkeley National Laboratory’s synchrotron radiation source in California, USA.

Pöhlker examined organic aerosol particles that were collected from air filters and small, paper-thin plates in the untouched Brazilian rainforest north of Manaus, which allowed the chemist to precisely measure the particles’ potassium content. “We identified three different kinds of or-ganic aerosol particles and they all contained potassium salts,“ Pöhlker explains. “Our initial focus was on the organic material’s carbon, oxygen, and nitrogen content. But then, to our surprise, we found its potassium content to be extremely high – almost 20 percent!“ Internal structures inside the nanometer- to micrometer-size particles point to the fact that during oxidation and condensation of organic gas molecules, multi-phase processes also play a role – which involve different chemical phases like fog or cloud water and other gel-like organic substances. The results will help with the identification and quantification of the sources and impact of organic aerosol particles under pre-industrial conditions. This in turn can help scientists understand how the rainforest’s continental and regional climate works and its role in Earth’s “climate machine.“

Publication: Science 31st August 2012 “Biogenic potassium salt particles as seeds for secondary organic aerosol in the Amazon,”
http://www.sciencemag.org/content/337/6098/1075.abstract

Contact and further information:

Christopher Pöhlker: c.pohlker@­mpic.de; Tel.: 06131 305-6303

Dr. Ulrich Pöschl: u.poschl@­mpic.de; Tel.: 06131 305-6201

arö

  • Copy link

You might also be interested in

  • Ernst Eckhard Koch Prize and Innovation Award on Synchrotron Radiation 2025
    News
    05.12.2025
    Ernst Eckhard Koch Prize and Innovation Award on Synchrotron Radiation 2025
    At the 27th BESSY@HZB User Meeting, the Friends of HZB honoured the dissertation of Dr Enggar Pramanto Wibowo (Friedrich-Alexander University Erlangen-Nuremberg). The Innovation Award on Synchrotron Radiation 2025 went to Prof. Tim Salditt (Georg-August-University Göttingen) and Professors Danny D. Jonigk and Maximilian Ackermann (both, University Hospital of RWTH Aachen University). 
  • Synchrotron radiation sources: toolboxes for quantum technologies
    Science Highlight
    01.12.2025
    Synchrotron radiation sources: toolboxes for quantum technologies
    Synchrotron radiation sources generate highly brilliant light pulses, ranging from infrared to hard X-rays, which can be used to gain deep insights into complex materials. An international team has now published an overview on synchrotron methods for the further development of quantum materials and technologies in the journal Advanced Functional Materials: Using concrete examples, they show how these unique tools can help to unlock the potential of quantum technologies such as quantum computing, overcome production barriers and pave the way for future breakthroughs.
  • The future of corals – what X-rays can tell us
    Interview
    12.11.2025
    The future of corals – what X-rays can tell us
    This summer, it was all over the media. Driven by the climate crisis, the oceans have now also passed a critical point, the absorption of CO2 is making the oceans increasingly acidic. The shells of certain sea snails are already showing the first signs of damage. But also the skeleton structures of coral reefs are deteriorating in more acidic conditions. This is especially concerning given that corals are already suffering from marine heatwaves and pollution, which are leading to bleaching and finally to the death of entire reefs worldwide. But how exactly does ocean acidification affect reef structures?

    Prof. Dr. Tali Mass, a marine biologist from the University of Haifa, Israel, is an expert on stony corals. Together with Prof. Dr. Paul Zaslansky, X-ray imaging expert from Charité Berlin, she investigated at BESSY II the skeleton formation in baby corals, raised under different pH conditions. Antonia Rötger spoke online with the two experts about the results of their recent study and the future of coral reefs.