Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Method Confirms Importance of Fungi in Arctic Nitrogen Cycle

10.05.2006


Cortinarius favrei grows in the midst of dwarf Betula and Salix, Vaccinium, and Eriophorum in the Alaskan tundra. At the Arctic LTER site, isotopic measurements indicate that mycorrhizal fungi function similar to this species contribute 60-90% of their plant’s nitrogen.


Technique Could be Applied to All Nitrogen-Poor Ecosystems

A new method to calculate the transfer of nitrogen from Arctic mushrooms to plants is shedding light on how fungi living symbiotically on plant roots transfer vital nutrients to their hosts. The analytical technique, developed by John E. Hobbie, MBL Distinguished Scientist and co-director of the laboratory’s Ecosystems Center and his son, Erik A. Hobbie of the University of New Hampshire, may be applied to nearly all conifers, oaks, beeches, birch and shrubs such as blueberry and cranberry—all nitrogen-poor ecosystems—and will be an important tool for future studies of plant nitrogen supply.

It has long been known when soil nitrogen is in short supply, mycorrhizal fungi (those living symbiotically on the roots of plants) transfer nutrients to their host plants in exchange for plant sugars derived from photosynthesis, but the rates of transfer have never been quantified in the field. John and Erik Hobbie’s study, published in the April 2006 issue of the journal Ecology, quantifies the role of mycorrhizal fungi in nitrogen cycling for the first time through measurements of the natural abundance of nitrogen isotopes in soils, mushrooms and plants. The researchers tested their technique using data from the Arctic LTER (Long Term Ecological Research) site near Toolik Lake, Alaska, in the northern foothills of the Brooks Range.



Previous research has found that when mycorrhizal fungi in the soil take up nitrogen from the soil and transfer it to small trees and shrubs, the heavy nitrogen isotope, nitrogen-15, is reduced in abundance in the plants and enriched in the fungi. Using a mass balance approach, an accounting of material entering and leaving a system, the researchers quantified the transfer of nitrogen and found that 61-86% of the nitrogen in plants at the site entered through fungal symbionts,

“Previous studies at this Arctic site have found a large range of nitrogen isotope content in plants and attributed the range to plants tapping into several different sources of nitrogen in the soil,” says John Hobbie. “Our study indicates that the differences can be attributed mainly to the presence or absence of symbiotic mycorrhizal fungi.”

The researcher’s new technique is shedding light not only on the nitrogen cycle in arctic tundra ecosystems, but can be applied to other nitrogen-poor ecosystems. “In the future, studies of plant nitrogen supply in all nitrogen-poor ecosystems must include these important transfers between plants and fungi,” says Hobbie.

Gina Hebert | EurekAlert!
Further information:
http://www.mbl.edu

More articles from Ecology, The Environment and Conservation:

nachricht Joint research project on wastewater for reuse examines pond system in Namibia
19.12.2016 | Technische Universität Darmstadt

nachricht Scientists produce a new roadmap for guiding development & conservation in the Amazon
09.12.2016 | Wildlife Conservation Society

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: 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...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

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

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

How gut bacteria can make us ill

18.01.2017 | Life Sciences

On track to heal leukaemia

18.01.2017 | Health and Medicine

Water - as the underlying driver of the Earth’s carbon cycle

17.01.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>