
Forests Around Chernobyl Aren’t Decaying Properly - Shivetya
http://www.smithsonianmag.com/science-nature/forests-around-chernobyl-arent-decaying-properly-180950075/
======
bostik
I saw a documentary about the Chernobyl exclusion zone a couple of years back.
One of the more interesting facts was that while the radioation levels on the
ground and soil surface have slowly gone down, the radiation levels from the
_trees_ are higher.

Explanation for this oddity was also provided, and like most things, makes
perfect sense in retrospect. The radioactive particles have been slowly washed
downwards in the soil, which explains the soil surface figures. But as the
particles get to the depth where trees and saplings have their roots, these
suck the particles in and eventually they get distributed in the leaves.

Funky, but oh so natural.

~~~
pasbesoin
In the months after Chernobyl, mushrooms e.g. in the Tirol and in Eastern
Europe were measured concentrating fallout up to 400x.

I'm not surprised that slower growing vegetation is showing an uptick.

~~~
politician
So, in the event of nuclear fallout, we could seed mushrooms everywhere to
clean it up? Maybe we should do that in Fukashima.

~~~
jmnicolas
But what do you do with the contaminated mushrooms ?

~~~
ecnahc515
_queue retro arcade music_ super Mario!

~~~
Dale1
lol!

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dangrossman
After a decade there's a couple extra inches of wood and leaf matter sitting
on the ground. I've always wondered what our planet looked like in the
millions of years between the evolution of trees, and the evolution of the
first fungus that could break down cellulose. With nowhere to go, those dead
forests eventually fossilized and became coal deposits -- but what was it like
to actually be there when those forests were growing. How thick did the dead
wood stack up? How did anything grow after the first few generations of trees
covered the ground in so much dead carbon?

~~~
Someone
Was there such a time? A quick google gives me, for trees,
[http://en.wikipedia.org/wiki/Evolutionary_history_of_plants#...](http://en.wikipedia.org/wiki/Evolutionary_history_of_plants#Tree_form)
_" The early Devonian landscape was devoid of vegetation taller than waist
height."_ and _" The first plants to develop this secondary growth, and a
woody habit, were apparently the ferns, and as early as the middle Devonian
one species, Wattieza, had already reached heights of 8 m and a tree-like
habit."_,

Comparing that with
[http://en.wikipedia.org/wiki/Evolution_of_fungi](http://en.wikipedia.org/wiki/Evolution_of_fungi)
_" A rich diversity of fungi is known from the lower Devonian Rhynie chert"_,
and lower Devonian = early Devonian, I very tentatively conclude fungi
precluded trees. Given that, I (not hindered by much specific knowledge of the
subject) expect that fungi breaking down cellulose co-evolved with trees.

~~~
grey413
Actually, the period between the development of woody plants and the
development of wood-eating fungi was approximately 60 million years, and is
known as the carboniferous because of all of the carbon that got sequestered.

Also, the key chemical wasn't cellulose, but rather lignin. Lignin is an
astoundingly complex polymer* that plants use as "concrete" to create their
woody cells. As far as I know, white rot fungi is the only group that can
break it down.

*seriously, look at that thing: [http://cse.ksu.edu/REU/S11/emd4y8/breakdown.html](http://cse.ksu.edu/REU/S11/emd4y8/breakdown.html). That's a big goddamn molecule.

~~~
croisillon
Great answer indeed! Now do you maybe have an idea of "how thick did the dead
wood stack up" as @dangrossman asked? Thanks !

~~~
TeMPOraL
Let's post it on whatif.xkcd.com :).

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todayiamme
As a potential solution, has anyone considered sprinkling the area with
graphite, massive amounts of graphite flakes? It's quite difficult to burn
nuclear grade graphite, and it might actually act as a moderator for the
fallout and help to control what's happening randomly.

Maybe the solution is to dump a moderator over the area and seed it with
organisms and see if something takes hold? Either way, this doesn't seem to be
an intractable problem if one is a bit lax in terms of long term uncertainty.
(this would throw off the projections of how this is going to play out 500
years from now)

~~~
grey413
To the best of my understanding, graphite in reactors serves the purpose of
moderating nuclear chain reactions. The radioactive materials in the forest
are almost certainly not dense enough to undergo a chain reaction, so adding a
moderator would be pointless. The issue isn't the environmental radiation
(like you might worry about standing next to an exposed nuclear core), it's
the prospect that radioactive materials might be absorbed by people (like you
might worry about if a nuclear core was on fire in the same city as you).
Spreading moderators around would do nothing to help about bioaccumulation.

~~~
dctoedt
> _The radioactive materials in the forest are almost certainly not dense
> enough to undergo a chain reaction, so adding a moderator would be
> pointless. ... Spreading moderators around would do nothing to help about
> bioaccumulation._

That's basically correct. There won't be a fission chain reaction because
essentially no neutrons are released by the radioactive decay of the isotopes
in the fallout. Consequently, deploying neutron moderators would have
essentially no effect. (It'd be like, say, taking a life jacket with you on a
hike through the Sahara.)

The relevant radioactive isotopes are mainly caesium 137, iodine 131, and
strontium 90 [1]. When they decay into other elements, they release beta- and
gamma radiation, which can damage nearby cells if ingested into the body. But
none of them fissions to release neutrons that would be absorbed by graphite
or boron.

The danger posed by these isotopes is that if you inhale or swallow them, they
can stick around in your body tissues, zapping nearby cells, for a long time.
For example, caesium 137 has an estimated biological _half_ life of 70 days
[2], while strontium 90, which is taken into bone much like calcium, has an
estimated biological half life of 18 years [3].

A major forest fire in the Chernobyl area would turn contaminated trees into
contaminated smoke. Who knows where the wind would blow the smoke. The
resulting fallout could be inhaled and/or swallowed by people and other
animals. It also might fall on farmland, where it could be up-taken by crops
that _would_ eventually be swallowed. All in all, not good news.

(Source: I used to be a Navy nuclear engineering officer.)

[1]
[http://www.who.int/ionizing_radiation/chernobyl/backgrounder...](http://www.who.int/ionizing_radiation/chernobyl/backgrounder/en/)

[2]
[http://en.wikipedia.org/wiki/Caesium-137#Health_risk_of_radi...](http://en.wikipedia.org/wiki/Caesium-137#Health_risk_of_radioactive_caesium)

[3]
[http://en.wikipedia.org/wiki/Strontium-90](http://en.wikipedia.org/wiki/Strontium-90)

------
keithpeter
What do we think of the experiment design? Good example? Anyone think of any
obvious flaws?

~~~
Someone
As nknighthb says, it's hard to say without access to the full paper. I
googled for it, but couldn't find it.

There are two things I noticed in the web page (not the paper) that triggered
questions immediately.

Firstly the claim "Because they had so many bags placed in so many different
locations, they were able to statistically control for outside factors such as
humidity, temperature and forest and soil type". The map only has 19 or so
locations. Seems a bit few to me to control for so many variables. Or am I
mistaken?

Secondly, the map has areas colored green, but the legend runs from yellow via
orange to red. What does green mean? Radiation at normal levels?

~~~
thisisdave
I believe this[1] is the paper (paywalled).

From the abstract:

>we deposited 572 bags with uncontaminated dry leaf litter from four species
of trees in the leaf litter layer at 20 forest sites around Chernobyl that
varied in background radiation by more than a factor 2,600

Depending on how much variation there is in microclimate and soil type within
their 20 locations, I could believe that they could get some pretty convincing
results from 572 bags. Especially if, as it appears from their claims, the
effect of radiation is very large relative to background noise.

On the other hand, the senior author:

* is not an expert in any related field as far as I can tell

* has been known to fabricate his data [2] and engage in borderline misconduct during the data analysis and writing phases as well [3].

I'm agnostic.

[1]:
[http://link.springer.com/article/10.1007%2Fs00442-014-2908-8](http://link.springer.com/article/10.1007%2Fs00442-014-2908-8)

[2]: [http://news.sciencemag.org/2004/01/ecologists-rocked-
miscond...](http://news.sciencemag.org/2004/01/ecologists-rocked-misconduct-
finding)

[3]:
[http://bio.fsu.edu/~dhoule/Publications/mollerreview.pdf](http://bio.fsu.edu/~dhoule/Publications/mollerreview.pdf)
(large PDF)

~~~
keithpeter
Latin square type design I presume. Thanks for posting this and spending the
time.

Given the record in your second reference, I'd imagine the lead author would
want to have the data out there and eye-balled by as many as possible to
improve reputation.

~~~
dalke
Some of the data is in link [1] as "Supplementary Material". This can be
downloaded without a fee. It isn't much though.

------
akiselev
Huh I'm curious about whether this is really that bad.

Eastern Europe (including and most of all, Russia) have peat lands which are
extremely dense decayed plant matter that has, over many many years,
compressed to the point where it has more carbon than coal. Russia's forest
fires (having killed tens of thousands in 2010 and 2012 each) are the worst
because the dense peat in the ground continues to burn through the years and
nothing but a _huge_ investment in landscaping will help put it out.

If decomposers are unable to create the peat as fast, it might make
controlling the fires far easier in the short term because the peat won't
continue burning, thus decreasing the risk of a catastrophic forest fire
spreading nuclear ash everywhere.

Edit: That said, peat takes thousands of years to build up so it might not
make any difference whatsoever.

~~~
saalweachter
More spin:

Carbon that is not decaying is carbon that is sequestered. If the trees don't
decompose, it removes carbon from the biosphere and ultimately from the
atmosphere.

Win!

------
not_that_noob
Excellent science. Of course, in retrospect, makes complete sense. Radiation
is used to sterilize food, so it's not surprising that it is doing the same
thing to the forest.

~~~
marcosdumay
I'm surprised. I'd expect micro-organisms to adapt faster to radiation than
plants, not slower.

~~~
yk
My guess is, for a micro-organism death of a single cell is deadly. So the
first photon that comes along kills. ( A bit more formal, irradiation effects
are probably proportional to the surface area, while available cells, and thus
ratio of destruction, is probably proportional to the volume. So relative
damage is proportional to 1/size.)

~~~
dalke
All light is made of photons. I think you mean "ionizing radiation", which
includes gamma rays (photons), as well as alpha particles, beta particles,
neutrons, etc.

I concur with Dylan16807; your physical model makes no sense. It means that
viruses would be killed if a gamma ray sneezed nearby, and it doesn't explain
D. radiodurans survivability.

It's likely going to be a function of DNA size, ability to repair DNA,
redundancy in the DNA, and lack of easily induced damaging side effects. None
of which are strongly correlated to cell volume.

~~~
yk
I am not talking about cell volume, I am talking about number of cells. So if
a single celled organism is hit by a gamma ray and a cell dies, it is dead. If
a tree looses a single cell, it will probably survive.

~~~
dalke
A single gamma ray rarely kills any cell, just like a single gamma ray rarely
kills a tree.

If there is a ton of single celled organisms, and enough radiation to kill 1/2
of them, then 1/2 a ton of single celled organisms remain.

If there is a ton of tree, and enough radiation to kill 1/2 of the cells, then
the tree is almost certainly dead.

And if I read the numbers correctly, you'll likely need more radiation to kill
a single celled organism cell than a tree cell.

------
bambax
Chernobyl: no fridge needed.

------
gmack
What about bioremediation? Bring in microorganisms, bacteria and fungal
spores, from healthy forests, and inoculate this one?

~~~
yummyfajitas
The issue is most likely that high radiation levels are inhibiting the growth
of microorganisms. So new microorganisms would probably just die.

Note that this is not particularly unexpected. We do this on purpose (in a
more controlled manner) to prevent spoilage of food and reduce food borne
illnesses.

[http://en.wikipedia.org/wiki/Food_irradiation](http://en.wikipedia.org/wiki/Food_irradiation)

------
runarb
Have anyone been to Chernobyl? I find the topic fascinating, and are
considering to go there to have a look for my self. Apparently there is
possible to have an guided tour into the exclusion zone. For example
[https://chernobyl-tour.com/english/](https://chernobyl-tour.com/english/) .

------
md2be
This is awesome science (I would say a little more worthy of a kickstarter
than Another burger joint). Fukushima is the Chernobyl of the sea, hopefully
someone will do similar research to study it.

~~~
tehwalrus
radiation underwater is much, much less harmful, because water is much more
dense than air.

[https://what-if.xkcd.com/29/](https://what-if.xkcd.com/29/)

~~~
deletes
Assuming the water is clean of radioactive particles( like dust or metal
fragments ).

~~~
tehwalrus
I would predict that such particles would be more dense, and sink over time to
the bottom.

However, there is the possibility of organisms eating them and then swimming
around. Nonetheless, the environmental damage should be greatly reduced.

------
agumonkey
What about the animal population that seems to have adapted enough to resist
the current radioactivity levels (source: some BBC documentary IIRC). I found
it fascinating.

~~~
dalke
I take it you didn't read the Smithsonian article? The second paragraph says:

> Birds around Chernobyl have significantly smaller brains that those living
> in non-radiation poisoned areas; trees there grow slower; and fewer spiders
> and insects—including bees, butterflies and grasshoppers—live there.

See also
[http://en.wikipedia.org/wiki/Effects_of_the_Chernobyl_disast...](http://en.wikipedia.org/wiki/Effects_of_the_Chernobyl_disaster#Plant_and_animal_health)
, which also points out that "[s]ome plants and animals have been able to
adapt to the increased radiation levels present in and around Chernobyl", but
then only lists the Arabidopsis plant.

There _is_ more animal diversity there now than before, but that can also be
attributed to it being more like a wildlife sanctuary.

~~~
agumonkey
I read it (without skimming even). But allow me to be surprised that,
considering what I remember about human populations impact (heavy and deadly
mutations in children), even with reduced organs, there are living animals
near the site.

~~~
dalke
This is likely because your baseline is not a wildlife sanctuary. You are
comparing the animal life in populated, pre-accident Chernobyl with farms and
agriculture, to depopulated, post-accident Chernobyl with little additional
human impact.

See
[http://www.slate.com/articles/health_and_science/nuclear_pow...](http://www.slate.com/articles/health_and_science/nuclear_power/2013/01/wildlife_in_chernobyl_debate_over_mutations_and_populations_of_plants_and.html)

> Those studies found mammal diversity and abundance equal to that of a
> protected nature reserve, with rare species including bears, lynx, river
> otter, and badger as well as introduced herds of European bison and
> Przewalski’s horses. Bird diversity is even richer and includes 61 rare
> species. Whooper swans—never before reported in the region—now appear
> regularly.

It points out that animal counts isn't the same as animal health, and it
suggests that a reason we don't see those animals born with 'heavy and deadly
mutations' is because they are quickly eaten by other animals.

------
ChuckMcM
I appreciate the care they went to in order to exclude other causes. I am not
surprised that microbes are more susceptible to ionizing radiation than larger
multi-cellular life given their structure. But I am surprised that they don't
make up for that in fecundity.

------
stcredzero
Reminds me of the grocery store scene from _28 Days Later_ \-- "Mmmmm!
Irradiated!"

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caycep
Hm, so that's how the forests in Nausicaa happened...

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ph0rque
_Unfortunately, there’s no obvious solution for the problem at hand..._

How about seeding the area with radiation-eating fungi, would that help?

~~~
maaku
That just redistributes the radiation into the fungi. Then what do you do?

~~~
swalsh
find an animal to eat the fungi, then collect all the dead fungi predators,
and place them deep in a mountain where we put nuclear waste?

~~~
grey413
The huge majority of any fungi tends to be in the ground or within it's host.

Plus the entire problem is quite likely that the wood/leaf eating fungi are
radiation sensitive, so...

------
pearjuice
>Click here to continue to the article

Dropped. Can anyone give a summary?

~~~
ssully
Yeah I can't believe those deceitful bastards at the Smithsonian would dare
float the idea of a possible subscription to their magazine before you read
their article.

~~~
Jtsummers
It isn't even that (at least I didn't get that). It's just a standard click
through advertisement that 90% of magazine sites seem to use. A lot of
interesting and informative articles are hidden away behind these pernicious,
easily skippable, advertisements.

~~~
ssully
While I agree completely that it's a bit outdated(sorry, potentially putting
words in your mouth) and has the potential to be pernicious(see the parent of
this thread), the easily skippable part is what makes it ok with me.

I found the subscription notice to be incredibly unoffensive given the
reputation of the source as well as the high quality of the article.

~~~
Jtsummers
No worries. I keep leaving off the /s. I think we're on the same page.

------
NextUserName
Wow, who would have expected that there is slow decay when microbes that decay
things are killed or slowed by radiation...

What a waste of time.

