Wood wide web: trees’ social networks are mapped

Research has shown that beneath every forest and wood there is a complex underground web of roots, fungi and bacteria helping to connect trees and plants to one another. This subterranean social network, nearly 500 million years old, has become known as the “wood wide web”. Now, an international study has produced the first global map of the “mycorrhizal fungi networks” dominating this secretive world.

Using machine-learning, researchers from the Crowther Lab at ETH Zurich, Switzerland, and Stanford University in the US used the database of the Global Forest Initiative, which covers 1.2 million forest tree plots with 28,000 species, from more than 70 countries. Using millions of direct observations of trees and their symbiotic associations on the ground, the researchers could build models from the bottom up to visualise these fungal networks for the first time. Prof Thomas Crowther, one of the authors of the report, told the BBC, “It’s the first time that we’ve been able to understand the world beneath our feet, but at a global scale.”

The research reveals how important mycorrhizal networks are to limiting climate change — and how vulnerable they are to the effects of it. “Just like an Magnetic Resonance Imaging scan of the brain helps us to understand how the brain works, this global map of the fungi beneath the soil helps us to understand how global ecosystems work,” said Prof Crowther. “What we find is that certain types of microorganisms live in certain parts of the world, and by understanding that we can figure out how to restore different types of ecosystems and also how the climate is changing.” Losing chunks of the wood wide web could well increase “the feedback loop of warming temperatures and carbon emissions.”

Mycorrhizal fungi are those that form a symbiotic relationship with plants. There are two main groups of mycorrhizal fungi: arbuscular fungi (AM) that penetrate the host’s roots, and ectomycorrhizal fungi (EM) which surround the tree’s roots without penetrating them.

(Claire Marshall. www.bbc.com, 15.05.2019. Adaptado.)

T E X T

Britain, Norway and the United States join forces with businesses to protect tropical forests.

Britain, Norway and the United States said Thursday they would join forces with some of the world’s biggest companies in an effort to rally more than $1 billion for countries that can show they are lowering emissions by protecting tropical forests. The goal is to make intact forests more economically valuable than they would be if the land were cleared for timber and agriculture.

The initiative comes as the world loses acre after acre of forests to feed global demand for soy, palm oil, timber and cattle. Those forests, from Brazil to Indonesia, are essential to limiting the linked crises of climate change and a global biodiversity collapse. They are also home to Indigenous and other forest communities. Amazon, Nestlé, Unilever, GlaxoSmithKline and Salesforce are among the companies promising money for the new initiative, known as the LEAF Coalition.

Last year, despite the global downturn triggered by the pandemic, tropical deforestation was up 12 percent from 2019, collectively wiping out an area about the size of Switzerland. That destruction released about twice as much carbon dioxide into the atmosphere as cars in the United States emit annually.

“The LEAF Coalition is a groundbreaking example of the scale and type of collaboration that is needed to fight the climate crisis and achieve net-zero emissions globally by 2050,” John Kerry, President Biden’s senior climate envoy, said in a statement. “Bringing together government and privatesector resources is a necessary step in supporting the large-scale efforts that must be mobilized to halt deforestation and begin to restore tropical and subtropical forests.”

An existing global effort called REDD+ has struggled to attract sufficient investment and gotten mired in bureaucratic slowdowns. This initiative builds on it, bringing private capital to the table at the country or state level. Until now, companies have invested in forests more informally, sometimes supporting questionable projects that prompted accusations of corruption and “greenwashing,” when a company or brand portrays itself as an environmental steward but its true actions don’t support the claim.

The new initiative will use satellite imagery to verify results across wide areas to guard against those problems. Monitoring entire jurisdictions would, in theory, prevent governments from saving forestland in one place only to let it be cut down elsewhere.

Under the plan, countries, states or provinces with tropical forests would commit to reducing deforestation and degradation. Each year or two, they would submit their results, calculating the number of tons of carbon dioxide reduced by their efforts. An independent monitor would verify their claims using satellite images and other measures. Companies and governments would contribute to a pool of money that would pay the national or regional government at least $10 per ton of reduced carbon dioxide.

Companies will not be allowed to participate unless they have a scientifically sound plan to reach net zero emissions, according to Nigel Purvis, the chief executive of Climate Advisers, a group affiliated with the initiative. “Their number one obligation to the world from a climate standpoint is to reduce their own emissions across their supply chains, across their products, everything,” Mr. Purvis said. He also emphasized that the coalition’s plans would respect the rights of Indigenous and forest communities.

From: www.nytimes.com/April 22, 2021