If you believe Hollywood, or its contemporary bodies around the world, radiation poisoning holds the potential to create anything from giant city-destroying lizards to a new race of humans, replete with exotic mutations making them capable of miraculous feats in defence of justice.
As you may have guessed, however, reality is seldom that poetic.
The nuclear threat has long been in the forefront of our minds. Since that first fateful detonation on the heavy weapons proving grounds of New Mexico’s shadowy military installations in 1945, which eventually culminated in the horrifically destructive nuclear attacks on the Japanese cities of Nagasaki and Hiroshima during World War II, the full extent of the danger posed by nuclear weapons has been notoriously well known to virtually everyone on the planet. The fear inspired by the danger has taken many forms over the decades since, and as Oscar Wilde opined “Life imitates Art far more than Art imitates Life.”
Because of what Wilde called Life’s self-conscious need to find expression, our silver screens and televisions have long been showing us images of what happens when nuclear energy is unleashed in unsafe ways. And today we are perhaps more aware of the dangers than any other generation, but that doesn’t mean our understanding is complete. Generally speaking, the public remains ignorant of just what radiation does to living cells. We think we know, but that knowledge is infected by popular culture and is coloured by our familiarity with monsters.
It would be difficult to find someone who isn’t presently aware of the danger flowing across the Pacific Ocean toward the continental US West Coast, from the crippled Japanese nuclear power plant at what is now officially called the Fukushima Daiichi nuclear disaster site. We are witnessing the worst nuclear disaster in our history, and though there is plenty of blame to be handed out for the failings in how it’s been dealt with since, Mother Nature is largely to blame for causing it in the first place. Of course, with such a disaster comes much conspiracy theorising and fear mongering, and few of the “facts” you’ll read about in this case are truly factual.
Surprisingly, the general public has learned little from our previous experience in this regard. The Chernobyl nuclear disaster, much of the details of which admittedly remain shrouded in secrecy, has offered us a unique view into the real effects of unrestrained exposure to nuclear radiation on the environment. And thus far, in the intervening 31 years, no giant indestructible monsters have emerged from the tundra of eastern Ukraine.
Scientists have recently found, however, that things in the exclusion zones aren’t as peaceful as they appear from afar. In fact, from a certain perspective, the hardest hit areas surrounding Chernobyl are a ticking time bomb, capable of renewing the danger it once presented. And the fuse on that bomb originates from the most unlikely of sources: decomposers.
From a study recently published in the journal Oecologia, it turns out that several scientists have found, surprisingly, that leaf litter on the forest floor in the exclusion zones isn’t decaying. Or, more accurately, that it isn’t decaying properly.
Through an ingeniously simple experiment, scientists from the University of South Carolina, Columbia found that the decomposition of leaves from areas with different levels of radiation exposure decomposed at strikingly different rates. They first became aware that there might be a problem when they noticed, through observational studies of the area since 1991, an unusual accumulation of leaf litter on the forest floor. The leaves that carpet the arboreal exclusion zones seem to form a blanket two to three times thicker than that of non-radiated forests. At first glance this seems to be because the leaves simply weren’t decaying, as would be natural anywhere else. Of course, when you consider why that might be, you must first understand the process of biological decay.
When a biological entity dies, whether that be a tree, an animal or a human being, there is an army of microscopic creatures who immediately go to work breaking down the structure of that entity. These microbes, small insects and bacteria consume various elements of the fallen entity, and release other elements back into the environment to be used by other living entities for sustenance. The great circle of life, as it were.
It’s long been known that wildlife in the exclusion zones has suffered in the years since the disaster; animals are smaller, with smaller brains, and they often sport physical deformities. The trees too, have suffered. The Red Forest – so named because its pine trees have died and turned red, but have yet to decay – offers many examples of trees and other plants that grow at a severely stunted rate. This suffering isn’t limited to creatures we can see though.
It turns out that those ever-important insects, microbes and bacteria are being affected as well, and that has a profound effect on the natural recycling process normally present in biology. The same mechanism that has affected other wildlife, has also affected the prevalence and efficiency of the creatures that are normally responsible for consuming dead biological material and recommitting it to the earth.
This has a dangerous effect on the overall ecosystem. It reduces the amount of basic nutrients in the soil, so that living plants struggle to survive, and it shields the soil and undergrowth from much needed sunlight. Ultimately this process, altered as it is, may result in unmeasured devastation to the biosphere in the area of Chernobyl. But, surprisingly, this isn’t the most immediate danger.
Biologist Timothy Mousseau, the lead author of the Oecologia paper, warns that the entire area of the Chernobyl disaster zone is at risk of wildfire. Obviously, an increase in dry leaf litter throughout the forests provides much fuel for a potential fire, but the major concern is that such a fire could release the dangerous nuclear isotopes currently trapped inside the trees and other plants, ejecting it back into the atmosphere and re-infecting the exclusion zones, and even perhaps increasing the affected area by a significant amount.
With all of this in mind, the Fukushima disaster comes into focus. Obviously there is little risk of wildfire in the Pacific Ocean, but those tiny creatures that are normally responsible for recycling biological material are everywhere. They do their work in the ocean just as much as the forest, but what doesn’t decay in the forest just lays on the ground, what doesn’t decay in the ocean can end up almost anywhere…bringing with it the poison of radiation.
The potential for these mechanisms to disseminate the dangerous nuclear isotopes around the world is frightening, to say the least, but letting fear cripple us serves no one. We must now attempt to understand the reach of these disasters, and we must find ways to mitigate the potential harm, not only to us, but to all life on the planet.
 Timothy A. Mousseau, Gennadi Milinevsky, Jane Kenney-Hunt, Anders Pape Møller. Highly reduced mass loss rates and increased litter layer in radioactively contaminated areas. Oecologia by Springer, March 14, 2014 http://link.springer.com/article/10.1007%2Fs00442-014-2908-8#