Megan Hall: Welcome to Possibly, where we take on huge problems like the future of our planet and break them down into small questions with unexpected answers. I’m Megan Hall. 

 You’ve probably heard of fungi, whether it’s mold in your bathroom or mushrooms on your favorite hiking trail, but recently, I’ve been hearing that fungi also play an underappreciated role in our climate. What’s that about? 

We had Harrison Katz and Juliana Merullo from our Possibly team look into this question. 

Harrison Katz: Hi, Megan!

Juliana Merullo: Hello! 

Megan Hall: So, first of all, what exactly are fungi?

Harrison Katz: You mentioned mold and mushrooms. Those are great examples! Fungi are a branch on the tree of life, separate from plants, animals, or bacteria. 

Juliana Merullo: They are actually more closely related to animals than they are to bacteria.

Megan Hall: Okay, so what do fungi have to do with climate change?

Harrison Katz: Well, one group of fungi, Mycorrhizae, has a special relationship with plants that makes them particularly interesting.

Megan Hall: What makes it special? 

Juliana Merullo: They actually help each other survive and thrive. These symbiotic relationships are pretty common in nature. 

Harrison Katz: Think… a bird that eats parasites off of a zebra’s back, or cleans between a crocodile’s teeth. The bird gets easy access to food, and the zebras and crocodiles get rid of parasites.

Megan Hall: Gotcha. And how do plants and this group of fungi interact? I’m guessing the fungi aren’t eating bugs off the plant bark!

Harrison Katz: Well, fungi turn out to be great at mining for nutrients in the soil, such as nitrogen and phosphorus. Mycorrhizae explore the soil using root-like growths which attach to plant roots.

Juliana Merullo: They use these root-like systems to gather nutrients which they give to plants. In exchange, the plants pump carbon from their leaves down to their roots and out into the fungal network, feeding the fungus.

Harrison Katz: And plants are great at using the sun’s energy to capture CO2 from the air. 

Megan Hall: So, when they team up, it helps remove carbon dioxide from the atmosphere.

Juliana Merullo: Exactly! This relationship between fungi and plants has been a key part of our living world since plants colonized land almost 400 million years ago. 

Harrison Katz: And this carbon sharing is much more important than it seems. These networks can grow to be massive. So massive that if you lined up all the Mycorrhizal fungus around the world, they would measure almost half the width of our galaxy.

Juliana Merullo: Since these fungi are a carbon sink like trees, just imagine how much carbon they keep out of the atmosphere!

Megan Hall: Wow! I had no idea there was so much fungus among us!

Harrison Katz: That’s not all. Mycorrhizal networks also help plants survive droughts and other periods of stress by giving extra nutrients in times of need. Without this support, plants would not be nearly as effective at pulling CO2 out of the air.

Juliana Merullo: Unfortunately, when a forest is cut, or fields plowed, fungal networks get disturbed, and they take time to come back. Chemical fertilizers can also kill off fungal populations in the area.

Megan Hall: So in addition to saving the forests, we need to save the fungi?

Juliana Merullo: Well, they go hand in hand. To save the forests, we definitely need to save the fungi. Luckily, there’s already been some progress on that front. 

Harrison Katz: An organization called the Fungi Foundation made headlines a few years ago when they lobbied the country of Chile to include Mycorrhizae in its list of environmental protections. 

Juliana Merullo: According to them, this is just the start, and they want to push for similar protections in other countries. 

Harrison Katz: The bottom line here is that diverse ecosystems do a lot for us, and even the parts that we can’t see, or don’t know about, can be very important for keeping everything working.

Megan Hall: Got it! Thanks, Harrison and Juliana! 

That’s it for today. For more information, or to ask a question about the way your choices affect our planet, go to the public’s radio dot org slash possibly. Or subscribe to us wherever you get your podcasts. 

You can also follow us on facebook and twitter- at “ask possibly” 

Possibly is a co-production of The Public’s Radio and Brown University’s Institute for Environment and Society and Climate Solutions Initiative.

The post How do fungi help combat climate change? appeared first on TPR: The Public's Radio.