Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Non-native earthworms may be wiping out rare plants

22.11.2002


Most of us don’t pay much attention to earthworms but maybe we should. New research suggests that non-native earthworms are radically changing the forest floor in the northern U.S., threatening the goblin fern and other rare plants in the process.


This is "the first research to show that exotic earthworms are harmful to rare native vegetation in northern forests," says Michael Gundale of Michigan Technological University in Houghton, who presents this work in the December issue of Conservation Biology.

About 10,000 years ago, glaciers pushed the range of North American earthworms southward and today the only earthworms found in most of Minnesota are non-native species introduced from Europe. Some of these earthworms eat the top part of the soil (a layer of decomposing litter called the forest floor) and this could endanger the goblin fern, a rare species that grows mostly underground.

Found only in the upper Great Lakes region, goblin ferns live between the forest floor and the underlying mineral soil. Because these tiny ferns only send up leaves briefly during the summer (and often don’t emerge at all), they are thought to get some of their energy from fungi in the forest floor instead of by photosynthesizing.



To see if non-native earthworms are wiping out goblin ferns by eating the forest floor, Gundale studied 28 sites where populations of the fern had previously been found in northern Minnesota’s Chippewa National Forest. He surveyed each site for both goblin ferns and earthworms, and took soil cores to measure the depth of the forest floor.

Gundale found that the fern had disappeared at a third of the sites studied (nine out of 28) and that these local fern extinctions were linked to two factors: the presence of a non-native earthworm and a thinner forest floor. The forest floor at "earthworm" sites was only half as thick as that at worm-free sites (about 1.5 vs. 3 inches, respectively).

To confirm that this non-native earthworm can make the forest floor thinner, Gundale added large quantities of the worm to soil cores in the laboratory. He found that after 60 days, the forest floor was only half as thick as it had been.

Gundale speculates that non-native earthworms may reach northern forests as eggs, which are resilient and so could be spread via tires. In support of this, he observed that earthworm invasions were more severe closer to roads.

Based partly on Gundale’s work, the U.S. Forest Service is trying to protect the goblin fern by restricting logging and road-building where it grows.


FOR MORE INFORMATION:

John Casson, Chippewa National Forest (jcasson@fs.fed.us)

Institute of Ecosystem Studies: Invasion of North Temperate Forest Soils by Exotic Earthworms: http://www.ecostudies.org/research/reports/grofrep2.html
For PDFs of papers, contact Robin Meadows: robin@nasw.org; http://nasw.org/users/rmeadows

For any photos provided by researchers:

To register for media access to the TOC and our expert directory: http://www.conbio.org/scb/information/media/

For more information about the Society for Conservation Biology: http://conservationbiology.org/

FAQ: SCB is developing a conservation biology FAQ; please help us make it useful to you by sending suggestions for questions to Robin Meadows: robin@nasw.org




Michael Gundale | EurekAlert!
Further information:
http://www.conbio.org/scb/information/media/
http://conservationbiology.org/

More articles from Ecology, The Environment and Conservation:

nachricht Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen

nachricht A new indicator for marine ecosystem changes: the diatom/dinoflagellate index
21.08.2017 | Leibniz-Institut für Ostseeforschung Warnemünde

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: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>