Radiation from the 1986 Chernobyl disaster is messing with local forests' ability to decay—and that's dangerous, both for local ecosystems and perhaps the area's neighbors. Researchers were concerned that decades after the disaster, dead trees in the area still hadn't decomposed, the Smithsonian notes. "We were stepping over all these dead trees on the ground that had been killed by the initial blast," Tim Mousseau says, per Red Orbit. "If a tree had fallen in my backyard, it would be sawdust in 10 years or so.” The experts decided to investigate the effects of radiation on microbes, bugs, and other organisms behind decomposition.
They distributed bags of untainted leaves in parts of the forests with varying amounts of radiation; the ones in the worst-affected areas decayed far more slowly. "The gist of our results was that the radiation inhibited microbial decomposition of the leaf litter on the top layer of the soil," says Mousseau. That's a problem for the ecosystem, because it means nutrients aren't making their way back into the soil. And those leaves could provide fuel for a "catastrophic" future forest fire. "This litter accumulation that we measured … is like kindling," Mousseau notes, via Nature World News. Such a fire could spread contamination into "populated areas," Mousseau says.