Another factor for long term persistence: religion
I’m cities across India where there are limited protections for flora and fauna, one can often see trees seen favorably in religion or even unfavorable in religion, survive while others perish. Trees that are viewed unfavorably are especially interesting. Peepal or Ficus religiosa is believed to harbor evil spirits in the folklore. You’d expect it to disappear from the landscape, but counterintuitive to the idea, they are some of the most commonly found trees in the cities. Reason: no one wants to upset the evil spirits by cutting down the tree. It’s sometimes near impossible to find people willing to even trim the trees down to keep them safe.
Legend based probably in true facts. Trimming or chopping any Ficus in tropical areas is dangerous, by the toxic sap. The burns will not appear until several hours later, so can be attributed to a revenge of supernatural actors.
nature-based religion in the slavic regions and into modern Finland definitely identified trees .. a huge turning point in the Christianization of the region by religious wars was the cutting of a certain sacred tree, with Christian Bishops and Charlemagne presiding
Weird title. The actual title is "Human activities and species biological traits drive the long-term persistence of old trees in human-dominated landscapes". Looks like the nonsense title here is the result of removing a bunch of words from the actual title. Maybe it was done automatically.
> identified which species were most likely to persist as old trees in human-dominated landscapes and where they were most likely to occur. We found that species with greater potential height, smaller leaf size and diverse human utilization attributes had the highest probability of long-term persistence. The persistence probabilities of human-associated species (taxa with diverse human utilization attributes) were relatively high in intensively cultivated areas. Conversely, the persistence probabilities of spontaneous species (taxa with no human utilization attributes and which are not cultivated) were relatively high in mountainous areas or regions inhabited by ethnic minorities.
Unsurprising results, but it's interesting seeing it quantified.
you must have access to this article.. looks like a paywall.
It seems rather important that the trees studied are in China and this is about natural history there. I was told casually that every natural forest in that part of the world has been substantially cut.. there is no "old growth" past some threshold.
Lastly, no mention of methods .. we are in an information age.
Amazonia itself has been called a "manufactured landscape". 10% of its soil is man-made terra preta. The distribution of many important plants like brazil nuts simply can't be explained without accounting for distributions of different peoples. 84% of all arboreal plants in the Amazon are known to be useful to humans[0] (edible, medicinal, etc). More likely than the Amazon magically just being a more special place is that the possibly 8-10 million[1] native inhabitants (pre colonial) selected and planted them.
California's increasingly dangerous wildfires are largely due to the fact that it banned traditional cultural burning (before California itself was even legally a state even!). These highly controlled "cool fires" got rid of fuel that now builds up and causes the devastating wildfires of today. They also cleaned rivers (due to the charcoal that was produced) and obviously helped acorns produce much larger bounties. These burns have been going on for at least 10k years so much of the flora is highly adapted. Some sage species can't even germinate without the presence of ashes. Despite this reliance on fire, they also simply can't handle the powerful wildfires of today
Many European colonists who came to Australia often described it as looking like a giant well-managed park. It turns out much of it really was. Similar to native Californians, complex fire regimes were often used for landscape management. But colonist writings also describe fields of pulled up grass that spanned out for many miles. It turned out aboriginals used hayricks to ripen seeds in the grass. They often grew native grains and would use it to make flour and bread.[2] If you'd like to read more, there's a great book on this topic called Black Emu: Dark Seed.
Everywhere you look humans have had to very tightly integrate into their ecosystems. This is why "conservation" practices are often criticized by indigenous activists for banning indigenous people from their lands. Our ecosystems are as dependent on us as we are on them and there's a desperate need for a more expansive definition of conservation that includes active interdependence with nature rather than trying to box away nature to preserve some idea of a "pristine landscape" that never actually existed
"The Amazon" and some of the other habitats you mention, all very different in their ecologies (and especially their relationship to fire), have had very complex histories, but their co-history with humans must be seen as a recent history in relation to the evolutionary history of their core community structures and the tens of millions of species of which they are composed. Of course once we first arrived in South America, only about 20,000 years ago, we had quite profound impacts on the Amazon's species composition and distribution, but... that's a mere 20,000 years ago, and essentially all the species we see in today's Amazon were already there, just configured differently. Before that, there was certainly a highly biodiverse and to all intents modern Amazon pre-dating humans by millions of years, one in which, if we could go back, we could still find regions plainly characteristic of every major present-day Amazonian ecotype, minus humans. This applies even more so to the much more ancient central African and southeast Asian rainforests in which there are also some areas with no clear record of inhabitation. I have done fieldwork in such areas and am fine with the characterization that they present a "more pristine" state of ecological affairs, as would most biologists focusing on tropical forest ecology rather than anthropology. To claim all these habitats are intrinsically human-oriented ecosystems that have always been as dependent on us as we on them is myopic. That's a view of how things have to be going forwards. But to them we're a recent development.
> Despite this reliance on fire, they also simply can't handle the powerful wildfires of today
Because the California fires of yore would roll through on a regular basis burning the limited fuel on the ground and not getting hot enough to damage the trees.
Now, after preventing natural burning for quite a while, there’s plenty of fuel sitting on the forest floor to get hot enough to kill all the trees.
No humans needed, lightning strikes are all you need to clear the forest floor every so often and keep the trees happy assuming you let nature take its course.
I don’t doubt that humans would clear land by burning but I do doubt that they had enough of an impact to change the entire ecosystem in the limited amount of time they were there.
Bruce Pascoe's book has received a lot of heavy criticism (including from some aboriginal groups). It isn't all wrong but is heavily biased and not reliable a source, so readers should be very careful drawing conclusions from it. I think most of what the parent says is right but be careful with the source.
[+] [-] darth_avocado|2 years ago|reply
I’m cities across India where there are limited protections for flora and fauna, one can often see trees seen favorably in religion or even unfavorable in religion, survive while others perish. Trees that are viewed unfavorably are especially interesting. Peepal or Ficus religiosa is believed to harbor evil spirits in the folklore. You’d expect it to disappear from the landscape, but counterintuitive to the idea, they are some of the most commonly found trees in the cities. Reason: no one wants to upset the evil spirits by cutting down the tree. It’s sometimes near impossible to find people willing to even trim the trees down to keep them safe.
[+] [-] pvaldes|2 years ago|reply
[+] [-] mistrial9|2 years ago|reply
[+] [-] Taywee|2 years ago|reply
> identified which species were most likely to persist as old trees in human-dominated landscapes and where they were most likely to occur. We found that species with greater potential height, smaller leaf size and diverse human utilization attributes had the highest probability of long-term persistence. The persistence probabilities of human-associated species (taxa with diverse human utilization attributes) were relatively high in intensively cultivated areas. Conversely, the persistence probabilities of spontaneous species (taxa with no human utilization attributes and which are not cultivated) were relatively high in mountainous areas or regions inhabited by ethnic minorities.
Unsurprising results, but it's interesting seeing it quantified.
[+] [-] dang|2 years ago|reply
(Submitted title was "Human activities drive long-term old trees in human-dominated landscapes".)
[+] [-] mistrial9|2 years ago|reply
It seems rather important that the trees studied are in China and this is about natural history there. I was told casually that every natural forest in that part of the world has been substantially cut.. there is no "old growth" past some threshold.
Lastly, no mention of methods .. we are in an information age.
[+] [-] culi|2 years ago|reply
Amazonia itself has been called a "manufactured landscape". 10% of its soil is man-made terra preta. The distribution of many important plants like brazil nuts simply can't be explained without accounting for distributions of different peoples. 84% of all arboreal plants in the Amazon are known to be useful to humans[0] (edible, medicinal, etc). More likely than the Amazon magically just being a more special place is that the possibly 8-10 million[1] native inhabitants (pre colonial) selected and planted them.
California's increasingly dangerous wildfires are largely due to the fact that it banned traditional cultural burning (before California itself was even legally a state even!). These highly controlled "cool fires" got rid of fuel that now builds up and causes the devastating wildfires of today. They also cleaned rivers (due to the charcoal that was produced) and obviously helped acorns produce much larger bounties. These burns have been going on for at least 10k years so much of the flora is highly adapted. Some sage species can't even germinate without the presence of ashes. Despite this reliance on fire, they also simply can't handle the powerful wildfires of today
Many European colonists who came to Australia often described it as looking like a giant well-managed park. It turns out much of it really was. Similar to native Californians, complex fire regimes were often used for landscape management. But colonist writings also describe fields of pulled up grass that spanned out for many miles. It turned out aboriginals used hayricks to ripen seeds in the grass. They often grew native grains and would use it to make flour and bread.[2] If you'd like to read more, there's a great book on this topic called Black Emu: Dark Seed.
Everywhere you look humans have had to very tightly integrate into their ecosystems. This is why "conservation" practices are often criticized by indigenous activists for banning indigenous people from their lands. Our ecosystems are as dependent on us as we are on them and there's a desperate need for a more expansive definition of conservation that includes active interdependence with nature rather than trying to box away nature to preserve some idea of a "pristine landscape" that never actually existed
[0] https://journals.plos.org/plosone/article?id=10.1371/journal...
[1] https://sci-hub.se/https://www.jstor.org/stable/24395921
[2] https://en.wikipedia.org/wiki/Bush_bread
[+] [-] Kaijo|2 years ago|reply
[+] [-] UncleEntity|2 years ago|reply
Because the California fires of yore would roll through on a regular basis burning the limited fuel on the ground and not getting hot enough to damage the trees.
Now, after preventing natural burning for quite a while, there’s plenty of fuel sitting on the forest floor to get hot enough to kill all the trees.
No humans needed, lightning strikes are all you need to clear the forest floor every so often and keep the trees happy assuming you let nature take its course.
I don’t doubt that humans would clear land by burning but I do doubt that they had enough of an impact to change the entire ecosystem in the limited amount of time they were there.
[+] [-] runsWphotons|2 years ago|reply