Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Forests around Chernobyl aren’t decaying properly (2014)

smithsonianmag.com

Post reply on HN
Print view View original

141–150 of 169 posts

Re: Forests around Chernobyl aren’t decaying properly (2014)

#141

Post by dEnigma »

godelski wrote: post #139
dEnigma wrote: post #134

Earlier quoted context omitted.

The thing that is unclear in your original comment is exactly what I was mentioning in mine. You didn't write what kind of threshold you were calculating here (which together with the bottom part of the comment made me think it was about actual radiation sickness). Now that you've made clear it's about the EU dosage limits I can easily follow. As I've said, there is a world of difference between where cancer risk beg…

I apologize, I thought you were being snarky. There's a few people in here that are not asking serious questions. I sourced a study on boar in Fukushima and ran similar calculations on that if you're interested. The conclusion is still similar: you need to eat an amount of pork that puts you at serious risk of cardiovascular disease and cancer from red meat before you have an increased risk of cancer due to the radia…

No worries. Re-reading your original comment I also realized that the quote you begin with talks about "dangerous levels" of radiation, which I suppose should prime one for the fact that you were talking about unsafe exposure levels. Regarding the "acute", I think I mixed up my previous "actual radiation sickness" with the "acute" in ARS there. You're right of course about it normally being used for short-term effects. So that would be another hint that what you were calculating was not the threshold for radiation sickness.

Re: Forests around Chernobyl aren’t decaying properly (2014)

#142

Post by hef19898 »

godelski wrote: post #140
hef19898 wrote: post #132

Earlier quoted context omitted.

You do realize that all those radiation doses do add up? I mean it is not as if boar is the only radioactive source, is it? You really seem to struggle to understand how limits for harmful sunstances are defined, and how those substances affect us and the environment.

> radiation doses do add up Yes and no. Acute exposure is not the same as protracted exposure. 10mSv in a microsecond is a vastly different risk than 10mSv over a year. Before you make such bold and obtuse claims, you may consider that this 20mSv safety limit includes radiation workers, who we haven't measured as having increased risk of cancer (even when the limits were higher). The relative risk starts around 50mSv…

I am not assuming anything. Facts so far: boar in Bavaria is exceeding radiation limits for nutrition and can thus not be used (differs through out Bavaria of course), these limits have been put in place for good reason (I do not open a discission about the validity of safe thresholds for potetially dangerous stuff) and that this problem is directly linked to Chernobyl.

Your argument was, I summarize, that is not bad, the thresholds are way to low anyway and don't hurt. In short, we should increase safe thresholds and move on, right? That's how stuff works so, and it is a repetition of the arguments all the VW apologists used to downplay the scandal. That line of argument is dishonest, IMHO.

We can continue to discuss all those other points I raised, or the official investigation reports. Otherwise we turn im circles, and I don't have time for that.

Re: Forests around Chernobyl aren’t decaying properly (2014)

#143

Post by daemin »

JodieBenitez wrote: post #137
anankaie wrote: post #136

Earlier quoted context omitted.

And then there is cork

Indeed... still used for wine bottles. I can't say I'm too happy with it though, given the amount of bottles spoiled by bad cork.

The screw top for wine bottles, one of the best inventions in recent decades.

Re: Forests around Chernobyl aren’t decaying properly (2014)

#144

Post by garganzol »

Dylan16807 wrote: post #56
thrashh wrote: post #14

Earlier quoted context omitted.

But that to me just says that radiation definitely delays growth and a little radiation already affects a much larger organism like a plant, it’s probably hurting smaller organisms much more.

Why would it hurt smaller organisms more?

Intrinsically, smaller organisms have fewer recovery mechanisms when compared to multicellular organisms. So, it kind of makes sense for them to be more susceptible to radiation.

At the low level, it boils down to the amount of energy an organism has at its disposal: prokaryotes have no mitochondria and thus cannot usually form multicellular organisms. If radiation hits an prokaryotic organism (i.e. a single cell) - it's alone by itself and probably well gone after the hit.

If radiation hits an eukaryotic (multicellular) organism, it still is able to compensate for that (to some degree) and still remains in the breeding pool for some time after the event.

The key difference between the two is the ability to reproduce itself after the damage.

Re: Forests around Chernobyl aren’t decaying properly (2014)

#145

Post by lazide »

samrus wrote: post #127
lazide wrote: post #92

Earlier quoted context omitted.

If the soil was sterilized the forest would be dead. The trees need soil microbes to survive.

Sensible hypothesis. Has it been confirmed?

That a forest requires living soil?

Extensively.

Re: Forests around Chernobyl aren’t decaying properly (2014)

#146

Post by [deleted] »

garganzol wrote: post #144
Dylan16807 wrote: post #56

Earlier quoted context omitted.

Why would it hurt smaller organisms more?

Intrinsically, smaller organisms have fewer recovery mechanisms when compared to multicellular organisms. So, it kind of makes sense for them to be more susceptible to radiation. At the low level, it boils down to the amount of energy an organism has at its disposal: prokaryotes have no mitochondria and thus cannot usually form multicellular organisms. If radiation hits an prokaryotic organism (i.e. a single cell) -…

[deleted]

Re: Forests around Chernobyl aren’t decaying properly (2014)

#147

Post by foo-bar-bat »

godelski wrote: post #138
_ph_ wrote: post #125

Earlier quoted context omitted.

I just had an exchange with a local hunter who claims that 60% of the shot boars are discarded and deposited for being over the radiation limits for food. If you feel happy eating them, please contact some Bavarian hunters to get some cheap meat.

I need to clarify, the calculations I used are based on 2,857 Bq/kg. The threshold for Germany is 600 Bq/kg. I'm not sure why anyone would be surprised that the German government sets high levels of safety. Japan put limits as 100 Bq/kg. The limits don't change the danger levels. Here's a study you may be interested in[0] > The minimum and maximum radiocesium concentrations were 87.1 Bq/kg FM and 8,120 Bq/kg FM, resp…

Please stop spamming this thread.

Re: Forests around Chernobyl aren’t decaying properly (2014)

#148

Post by rtkwe »

Beldin wrote: post #60
rtkwe wrote: post #10

Earlier quoted context omitted.

Most of the exclusion zone is pretty low levels of radiation so I'm not sure how effective those are other than that they're an elevated background level. The FDA says 10 kGy is used for actual sterilization. Most of the zone is https://www.fda.gov/food/irradiation-food-packaging/overview... .

There are 365×24 = 8760 hours in a year. So after 1 year and 52 days, we've crossed this threshold - at current levels. So: thoroughly sterilised, if the FDA isn't totally off.

There's a significant difference between acute and chronic doses, the FDA are for acute dosing and there's not really numbers out there for chronic doses over that long of a timeframe with respect to food safety because it's not used. Also bacteria reproduce much faster than a year so maybe it keeps the numbers down by killing older generations sooner but it's not going to sterilize.

Re: Forests around Chernobyl aren’t decaying properly (2014)

#149

Post by rtkwe »

garganzol wrote: post #144
Dylan16807 wrote: post #56

Earlier quoted context omitted.

Why would it hurt smaller organisms more?

Intrinsically, smaller organisms have fewer recovery mechanisms when compared to multicellular organisms. So, it kind of makes sense for them to be more susceptible to radiation. At the low level, it boils down to the amount of energy an organism has at its disposal: prokaryotes have no mitochondria and thus cannot usually form multicellular organisms. If radiation hits an prokaryotic organism (i.e. a single cell) -…

The other option is they reproduce before the damage happens, bacteria multiply quickly and being small it's less likely any one individual will get struck and killed. The FDA numbers are for acute doses so you can kill everything in a package at one time, a chronic dose of the same overall amount spread out won't sterilize because you're not going to destroy every bacteria at once.

Re: Forests around Chernobyl aren’t decaying properly (2014)

#150

Post by pfdietz »

EdwardDiego wrote: post #66
pfdietz wrote: post #59

Earlier quoted context omitted.

Actually, burning of trees helped reduce CO2 over the long term. That's because burning is incomplete and produces charcoal. Charcoal doesn't decay, so when it is buried it semi-permanently takes carbon out of the biosphere. Over extended time, this would draw down atmospheric CO2. Some coal deposits from that period have a significant fraction of charcoal in them.

IIRC, that's lignite coal?

I don't think so? The charcoal would remain identifiable as the coal is matured by burial and heating (perhaps not all the way to anthracite).
Post reply on HN