The Daily Populous Monday November 11st, 2024 morning edition
Authored by news.ucr.edu and submitted by bojun

When Mount St. Helens erupted in 1980, lava incinerated anything living for miles around. As an experiment, scientists dropped gophers onto parts of the scorched mountain for only 24 hours. The benefits from that single day were undeniable -- and still visible 40 years later.

Mt. St. Helens erupting in 1980. (CoreyFord/iStock/Getty)

Once the blistering blast of ash and debris cooled, scientists theorized that, by digging up beneficial bacteria and fungi, gophers might be able to help regenerate lost plant and animal life on the mountain. Two years after the eruption, they tested this theory.

“They’re often considered pests, but we thought they would take old soil, move it to the surface, and that would be where recovery would occur,” said UC Riverside microbiologist Michael Allen.

They were right. But the scientists did not expect the benefits of this experiment would still be visible in the soil today, in 2024. A paper out this week in the journal Frontiers in Microbiomes details an enduring change in the communities of fungi and bacteria where gophers had been, versus nearby land where they were never introduced.

“In the 1980s, we were just testing the short-term reaction,” said Allen. “Who would have predicted you could toss a gopher in for a day and see a residual effect 40 years later?”

An unhappy gopher and plant near the gopher enclosure fence, 1982. (Mike Allen/UCR)

In 1983, Allen and Utah State University’s James McMahon helicoptered to an area where the lava had turned the land into collapsing slabs of porous pumice. At that time, there were only about a dozen plants that had learned to live on these slabs. A few seeds had been dropped by birds, but the resulting seedlings struggled.

After scientists dropped a few local gophers on two pumice plots for a day, the land exploded again with new life. Six years post-experiment, there were 40,000 plants thriving on the gopher plots. The untouched land remained mostly barren.

All this was possible because of what isn’t always visible to the naked eye. Mycorrhizal fungi penetrate into plant root cells to exchange nutrients and resources. They can help protect plants from pathogens in the soil, and critically, by providing nutrients in barren places, they help plants establish themselves and survive.

“With the exception of a few weeds, there is no way most plant roots are efficient enough to get all the nutrients and water they need by themselves. The fungi transport these things to the plant and get carbon they need for their own growth in exchange,” Allen said.

A second aspect of this study further underscores how critical these microbes are to the regrowth of plant life after a natural disaster. On one side of the mountain was an old-growth forest. Ash from the volcano blanketed the trees, trapping solar radiation and causing needles on the pine, spruce, and Douglas firs to overheat and fall off. Scientists feared the loss of the needles would cause the forest to collapse.

That is not what happened. “These trees have their own mycorrhizal fungi that picked up nutrients from the dropped needles and helped fuel rapid tree regrowth,” said UCR environmental microbiologist and paper co-author Emma Aronson. “The trees came back almost immediately in some places. It didn’t all die like everyone thought.”

On the other side of the mountain, the scientists visited a forest that had been clearcut prior to the eruption. Logging had removed all the trees for acres, so naturally there were no dropped needles to feed soil fungi.

“There still isn’t much of anything growing in the clearcut area,” Aronson said. “It was shocking looking at the old growth forest soil and comparing it to the dead area.”

These results underscore how much there is to learn about rescuing distressed ecosystems, said lead study author and University of Connecticut mycologist Mia Maltz, who was a postdoctoral scholar in Aronson’s lab at UCR when the study began.

“We cannot ignore the interdependence of all things in nature, especially the things we cannot see like microbes and fungi,” Maltz said.

TikkiTakiTomtom on November 11st, 2024 at 02:55 UTC »

For those that didnt read it, researchers on a whim took gophers (considered as pests) to barren land around St. Helen for one day in the 19__’s. They never would have believed the residual effects of that single day could still be observed 40 yrs later. Barren land that had gophers, recovered and flourished; land without remained barren to this day. The animals’ impact as part of ecological system as seen here is so important

Curiouserousity on November 11st, 2024 at 02:51 UTC »

It's the fungus, specifically the soil fungus that was trapped in the old topsoil covered by pumice and ash. Fascinating stuff.

NeroBoBero on November 11st, 2024 at 01:45 UTC »

Brought a volcano back to life? How deep were they digging?