Chernobyl's forests

Chernobyl's Trees Won't Decay, Increasing the Risk of Nuclear Forest Fire

VICE,

16 March, 2-14

As if the Ukraine didn’t have enough to worry about these days with Russia invading Crimea, recent scientific research points to the very real threat of a nuclear forest fire. Great heavy metal band name aside, the forests around Chernobyl—the nuclear power plant that exploded 28 years ago—are not decaying properly and should it all catch fire, radioactive material would spread beyond Chernobyl’s Zone of Alienation, the off-limits 1000 square-miles around the decommissioned facility located 68 miles north of Kiev.

This Zone of Alienation has given environmental scientists much to study, with insects choosing to not live there and the birds that do live there developing abnormalities like deformed beaks, odd tail feather lengths, and smaller brains. The trees too, have been shady.  

Image: Inside Pripyat, one of Chernobyl's evacuated cities/Eero Nevaluoto

Scientists who have been studying the environment inside the Zone of Alienation since 1991 noticed something about these trees, specifically what they described as “a significant accumulation of litter over time” in a study published recently inOecologia. And by “significant,” they mean the trees are not decomposing and their leaves are just sitting there on the ground, not decomposing either. This is especially so in the Red Forest, an area of woodland around Chernobyl named thusly because the trees turned a ginger color and died due to the worst radiation poisoning in the area. In an interview with Smithsonian magazine, lead author of the study and biologist at the University of South Carolina Timothy Mousseau called all this non-decayed organic matter “striking, given that in the forests where I live, a fallen tree is mostly sawdust after a decade of lying on the ground.”

The reason for this lack of decay around Chernobyl is that microbes, bacteria, fungi, worms, insects, and other living organisms known as decomposers (because they feed on dead organisms) are just not there and not doing their jobs. Mousseau and his team discovered this after leaving 600 bags of leaves around Chernobyl in 2007. When they collected the bags in 2008, they found that the bags filled with leaves placed in areas with no radiation had decomposed by 70 to 90 percent, but the leaves in areas with radiation? They only decomposed about 40 percent. “There is growing concern that there could be a catastrophic fire in the coming years,” Mousseau told Smithsonian.

Besides getting rid of what is basically tinder for wildfires, decomposers are essential when it comes to plant growth because they put nutrients back into the soil, and back into the environment generally. The lack of decomposers could also explain why the trees that are alive around Chernobyl are growing very slowly. 

These Chernobyl trees cover about 660 square miles of the Zone of Alienation and have been absorbing radionuclides like strontium 90 (causes bone cancer) and cesium 137 (effects range from nausea to death) for almost three decades. If these trees are burned, these radionuclides would be released into the atmosphere as “as inhalable aerosols” reported Scientific American last year, citing a 2011 study. Besides inhaling cancer-causing particles in the air traveling hundreds of miles away, the biggest threat would be to food like milk and meat “produced as far as 90 miles from the fire.”

In fact, the threat of a Zone of Alienation wildfire spewing radioactive particles has been a concern among environmental scientists since 1992. The threat has only gotten worse due to the longer, drier summers attributed to climate change.  

There are firefighters stationed around the Zone of Alienation specifically for preventing a forest fire inside, but they’re “obviously not prepared for a major wildfire situation” says SA, with hardly any “professional training, protective suits or breathing apparatuses.” Firefighters currently scout for fires by climbing six watch towers a day, along with the help of one helicopter that is “occasionally available.” They do have a Soviet tank that has been retrofitted with a 20-foot-blade though, to chop down and crush the dead trees that refuse to decay currently littering the roadways.