Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Without disturbances in nature the world’s forests will be impoverished

21.06.2004


The forests of the world are not the stable and unchanging ecosystems they have been assumed to be. Without the occurrence of wide-spread disturbances in nature, such as forest fires, icing, or volcanic activity, forests will eventually be impoverished, owing to a lack of phosphorous.

This is shown in a study reported in this week’s issue of the journal Science. The scientists who carried out the investigation are David Wardle, Department of Forest Vegetation Ecology, Swedish University of Agricultural Sciences (SLU), Sweden, Richard Bardgett, University of Lancaster, U.K., and Lawrence Walker, University of Nevada, U.S.

The three researchers have examined soil profiles from forested land in six places around the world: in Arjeplog in Swedish Lapland, Alaska, Hawaii, Eastern Australia, and southern New Zealand (two locations). In all places there are soils of extremely varying age, from very young to several thousand years old. The oldest soil, in Hawaii, was 4.1 million years old.



In all six locations forests grew least well in the oldest soils, because the access to absorbable phosphorous was limited in comparison with access to absorbable nitrogen. When soils age, less phosphorous becomes available to trees, since phosphorous is not biologically replenished in the soil or supplied to the ecosystem in any other way. Nitrogen, on the other hand, is renewable; atmospheric nitrogen is continuously supplied to the soil and is tranformed by soil bacteria to forms of nitrogen that the trees can take up. It is not a lack of nitrogen, as has previously been thought, but a lack of phosporous that lies behind poor growth in forests when they become old.

The shortage of phosphorous in the older soils also influenced the soil organisms in a negative manner, reducing their ability to release soils nutrients. The scientists draw several conclusions from their findings. First of all, they show that greater disturbances are necessary if we wish to renew forest ecosystems. What type of disturbances are required varies with soil type, but forest fires, icing, or volcanic activity can be mentioned. If such disturbances do not occur, forests cannot be endlessly renewed. Ultimately the lack of phosphorous will become such a hindrance that the soil will no longer be able to provide sufficient nourishment for densely planted forests with large trees.

A second conclusion is that productive forests are temporary, seen from the perspective of a thousand or ten thousand years: if no disturbances occur in nature, then such forests will slowly be impoverished. The patterns for how this impoverishment takes place, and its underlying mechanisms, are the same, regardless of what type of forest it is and where it is located on earth. The same processes occur in boreal, temperate, and tropical climates, albeit at different rates.

Carin Wrange | alfa
Further information:
http://www.svek.slu.se

More articles from Studies and Analyses:

nachricht New study: How does Europe become a leading player for software and IT services?
03.04.2017 | Fraunhofer-Institut für System- und Innovationsforschung (ISI)

nachricht Reusable carbon nanotubes could be the water filter of the future, says RIT study
30.03.2017 | Rochester Institute of Technology

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

DGIST develops 20 times faster biosensor

24.04.2017 | Physics and Astronomy

Nanoimprinted hyperlens array: Paving the way for practical super-resolution imaging

24.04.2017 | Materials Sciences

Atomic-level motion may drive bacteria's ability to evade immune system defenses

24.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>