Comment by jcattle
19 hours ago
Just an aside: I'm a researcher trying to classify forest disturbance types from satellite imagery.
The Landes Forest which is currently burning is really interesting in that you have all 4 of the major European disturbance types there: Human clear cuts, storm damage, large scale insect infestation and fire.
Most other forested areas in Europe only have two or three of these. For example most of the Mediterranean does not have meaningful amount of storm damage.
Just shows how badly suited the Landes Forest with its current forest management is in todays climate.
How can you identify large scale insect infestation from satellite imagery?
With freely available satellite imagery you're looking at a 10x10m resolution per pixel.
So basically entire tree stands have to die or crowns have to lose their leafs for it to be detectable form space.
Main insect of concern are bark beetles (ips typographus for spruce, ips sexendtatus for pines) which disrupt the cambium causing a gradual vitality decline until you have dead standing trees. In satellite imagery this is visible as irregular brownish-red patches.
On the other hand there's gypsy moths (also known as spongy moth, Lymantria dispar) which affect the leafs directly, causing large scale temporary defoliation in broadleafed trees usually in the middle of summer.
There's hundreds more insects but few have the capability to cause large scale die-off in trees which are grown in monoculture (pine/spruce/beech).
Do you happen to know if firebreaks or fuelbreaks are used in some of these forests? Are they seen as effective? Are they costly to set up?
From what I saw online, there are indications that firebreaks do not always work, for instance when embers fly over long distances, carried by the wind, over firebreaks, and start fires on the other side. But I would guess that firebreaks like cleared areas, for instance between settlements and forests, should be able to mitigate at least some of the fires.
They are firebreaks everywhere in this forest, you can see them from satellite images, but the fire can jump, and it's mainly used as a defense line by firefighters. I was in this forest 2 weeks ago and the ground which is layered with pine needles was so dry that it was just a question of time.
Do you not just make them much wider?
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Interesting. Have you tried back testing your model agains fire data to analyze how well you could predict fire likelihood?
No, at the moment classifying disturbances is only done retrospective. Predicting fire likelihood is its own large area of research.
An open case is more in terms of temperate forests which are increasingly starting to burn, for example in Austria or other central European countries. These tend to be understory fires, which (for now) only rarely catch the crown.
For these fires the tree crown stays green and you can't see any change until later in the year or the next year, where the trees die due to damage the fire did to their cambium and roots. Correctly attributing this later decline to fire damage is a bit challenging.
The Landes Forest is a human disturbance.
The whole damned thing was planted in the 1850s as an enormous pine plantation.
Same thing as drives wildfires in Portugal - maritime pine (and in Portugal’s case eucalyptus). Vast, dense, barely managed pyrophytic monocultures. The problem isn’t poorly managed forest, it’s the forest, period - it shouldn’t be there.
https://en.wikipedia.org/wiki/Landes_forest
Yes, the same problem exists in the north of Spain. They long ago cut down native forests to plant vines and farm cattle, but once that ceased to be profitable they replanted it all in monoculture pine and eucalyptus.
Where native forest (oak, chestnut, hazel, etc) remains, we don't have major fires. They are finally experimenting with planting firebreaks of native species in some areas, which has been quite effective at halting the spread of fires. But realistically, we need a huge government investment to get rid of this monoculture entirely.
> Where native forest (oak, chestnut, hazel, etc) remains, we don't have major fires.
Not really. It helps, but it is not a perfect solution. It did not prevent the massive wildfire near Fontainebleau, for example.
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Yes, I'm well aware that Landes naturally should be an extensive sandy marsh.
With how natural forest disturbances are more and more starting to affect the plantation, it proves to be seen what the response will be.
The thing is that it is an incredibly productive forest (only in terms of biomass). So now there's a bunch of capital riding on it which will have a vested interest to keep it productive.
>Yes, I'm well aware that Landes naturally should be an extensive sandy marsh.
No, it shouldn't. It used to be a forest but was cut down by firewood and sheep grazing.
Stop with the "return to nature" fallacy. With how things are going, even "natural" forests are going to burn down.
As an aside, N. III's reign seems to have been overall something of a disaster for the French.
To be fair, that's more the Third Republic's verdict than what recent historians have concluded. For sure, Sedan was a catastrophe and the Mexican adventure was worse, but the two decades in between gave France the railway build-out, Haussmann's Paris, the creation of modern investment banks, and even universal male suffrage, which the Republic then kept ([1], [2] & [3]).
In this particular instance, everybody in this thread seems to be forgetting the region where the fires are currently raging used to be very unsanitary swamps before the pine forests were planted. These older wetlands were a major source of disease and misery for the local population. The reason why they only planted pines were because the soil there is poor & acidic. Nothing else grows really. Now of course, this needs to be rethought in the light of climate change, but it wasn't a stupid idea at the time.
[1] The unlikely triumph of Napoleon III, https://engelsbergideas.com/reviews/the-unlikely-triumph-of-...
[2] Napoleon III and the Second Empire, https://www.routledge.com/Napoleon-III-and-the-Second-Empire...
[3] The People's Emperor, https://www.faber.co.uk/product/9780571361304-the-peoples-em...
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It’s more nuanced. He massively helped with industrialisation, for example. He was doing ok in his liberal years. But he had different phases and some were better than others.