Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The contribution of particulate matter to forest decline

19.06.2013
Air pollution is related to forest decline and also appears to attack the protecting wax on tree leaves and needles.

Bonn University scientists have now discovered a responsible mechanism: particulate matter salt compounds that become deliquescent because of humidity and form a wick-like structure that removes water from leaves and promotes dehydration. These results are published in “Environmental Pollution”.

Nature conservationists call it “lingering illness”, and the latest report on the North-Rhine Westphalian forest conditions confirms ongoing damage. Bonn University scientists have now shown that salt deposits on leaves may decrease the drought tolerance of trees, thereby contributing to forest decline. “Our study reveals that so-called wax degradation on pine needles may develop from deposited particulate matter”, says Dr. Jürgen Burkhardt from the Institute of Crop Science and Resource Conservation. Wax helps to protect leaves and needles from water loss.

It has long been known that air pollutants accelerate wax ageing and that “wax degradation” is closely related to forest damage. “Wax degradation was addressed by many studies in the 1980s and 90s, but sound explanations for both the degradation mechanism and the high correlation with forest damage have yet been missing”, Dr. Burkhardt reports. Previous approaches assumed chemical reactions for wax degradation, whereas the present study reveals physical reasons. “The deposition of hygroscopic salts is capable of decreasing the drought tolerance of trees”, co-author Shyam Pariyar says.
Accelerated dehydration of needles treated with salt solutions

The scientists sprayed salt solutions on Scots pine needles and recorded their weight loss after abscission. The needles treated with salt solutions dried out significantly faster than the untreated control needles. Using an electron microscope, the scientists observed the salts becoming deliquescent and moving into the stomata of the needles. Stomata are tiny pores used by plants to take up carbon dioxide for photosynthesis and release water vapor and oxygen. The deliquescent salts form very thin liquid connections between the surface and interior of the needle, and water is removed from the needles by these wick-like structures. Because the plants are unable to counteract this removal of water, the plants dehydrate more rapidly. Therefore, polluted air containing large amounts of particulate matter may directly reduce the drought tolerance of trees. Simultaneously, the deliquescent salts make wax appear “degraded”. “This newly described mechanism was not considered in earlier explanations of Central European forest decline”, states Dr. Burkhardt.

Conceivable aggravation of forest decline by climate change

A new type of electron microscope enabled the observation of particle deliquescence and dynamics under changing air humidity. In addition, a long-lasting scientific paradigm had excluded any aqueous movement into the stomata, and only recently had Bonn University scientists confirmed its existence (http://www3.uni-bonn.de/Pressemitteilungen/227-2012).

Recently, regional forest damage has been reported in the western USA and other parts of the world. A relationship with increasing climate change-type drought has been proposed, but the newly discovered mechanism involving particulate matter might contribute to the regional forest damage. “Particularly because air concentrations of hygroscopic particles have largely increased within the last decades”, says Dr. Burkhardt.

The study was funded by the Deutsche Forschungsgemeinschaft and the European Union (project ÉCLAIRE).

Publication: Particulate pollutants are capable to `degrade´ epicuticular waxes and to decrease the drought tolerance of Scots pine (Pinus sylvestris L.), “Environmental Pollution”, DOI: 10.1016/j.envpol.2013.04.041
Contact:

Dr. Jürgen Burkhardt
University of Bonn
Institute of Crop Science and Resource Conservation
Plant Nutrition Group
Phone. +49 228 732186
E-Mail: j.burkhardt@uni-bonn.de

Johannes Seiler | idw
Further information:
http://www.uni-bonn.de

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: 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...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

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

Helmholtz International Fellow Award for Sarah Amalia Teichmann

20.01.2017 | Awards Funding

An innovative high-performance material: biofibers made from green lacewing silk

20.01.2017 | Materials Sciences

Ion treatments for cardiac arrhythmia — Non-invasive alternative to catheter-based surgery

20.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>