Indeed, which is why the title is so strange. Sauropods are a strange thing to compare with anyway, I would compare it with other methods actually used for working the land.
The comparison comes because they're trying to draw conclusions about the effects of large sauropods on the prehistoric environment from modern experience with mechanized agriculture.
"As the total weight of modern harvesters is now approaching that of the largest animals that walked Earth, the sauropods, a paradox emerges of potential prehistoric subsoil compaction. We hypothesize that unconstrained roaming of sauropods would have had similar adverse effects on land productivity as modern farm vehicles, suggesting that ecological strategies for reducing subsoil compaction, including fixed foraging trails, must have guided these prehistoric giants."
This is strange because the subsoil composition of today vs. 65+ million years ago, let alone 250 million years ago, is substantially different. Mostly different insects, different bacteria, and though Earthworms did exist for much of that period, other types of worms did not. Lignin was already in trees and mushrooms were already in the ground, but soil as a living ecosystem was far less developed and alive than it is today - it was probably closer to regolith at least in the 250-100 million year ago period.
I've been listening to Nick Offerman read The World-Ending Fire: The Essential Wendell Berry. Wendell talks about using horses instead of tractors - the impact on the land and the economics. (using horses is just a small part of the economics - a community / local approach being a large aspect of Berry's writings)
Coming soon: Chris Pratt using a team of sauropods to farm in the next Jurassic Park movie.
Sauropods are presumably the heaviest things we know to have worked the land in anything like a sustainable way: being herbivores they obviously can't survive for long as a species if they permanently damage the soil to the point of being unproductive simply by walking on it.
It would be fair to object that what was unsustainable by plants then might not be a problem for more modern plants, but I'm not sure what your comment about other methods aims at. The uncertainty comes from machines reaching previously unexplored weights, comparing with soil effects from lighter methods is unlikely to tell you if there's something bad coming.
All we know is that it apparently worked for Sauropods, not what the upper limits are, and it need not have been sustainable, that depends on how big an area they were covering and how many of them there were, that it was sustainable is something the article seems to assume without further consideration.
Other methods are more applicable because we actually have data on what works and what doesn't with respect to soil loading, farmers really do not want to damage their land ('damage it in an hour, take a decade to recover') and have learned the hard way not to overload the soil already.
The resistance of soil to compaction is totally different in a forest with mighty trees and roots, where these beasts presumably roamed, and a barren field of dirt.
And secondly, 'sustainable' to a heart of wild beasts does not mean harvest every year - maybe the heard comes back in 20 years when soil has recovered.
Lastly, maybe they wheren't sustainable, after all they are extinct.
> Lastly, maybe they wheren't sustainable, after all they are extinct.
I mean, they existed for tens of millions of years (according to wikipedia), which is 1000's of times longer than the entirety of human farming; I think this easily classified as "sustainable".
Yes. I think GP’s point is that dinosaurs and big tractors are different enough that it’s unwise to dismiss concerns about this as “well, it worked for the dinosaurs.”
Mass and ground loading is just one part of the picture. Roam area, root structure, etc make a difference.
The point of the article is that from the fact current heavy tractors are ruining soils we should wonder how Sauropods managed to survive despite being worse for the soil.
Oh, thats easy - we are 8 billion, sauropods were a few million. We can't digest cellulose, and sauropods could. We eat mean, and sauropods didn't.
If you can digest tree bark and have 5 square kilometers per person you can damage the soil as much as you want, something will still grow.
But if you want civilisation to survive, we need a regular harvest of 40 tons per hectare for potato, and if that number falls to 20 there is a famine.
The Sauropods where around for over 20 million years though, but moving at an average of 1 m/s it doesn't take even a year to visit all square metres inside the allotted box.
That number was for a human - a hectar of land can feed a person, so 500 hectars can feed a person even if you are inefficient, damaging the soil, etc.
You are the one advocating we live like Sauropods, so you should be telling us what was the roaming range of one - a male bobcat has roaming range of 20 to 70 sq. Kilometers
I just skimmed the abstract but it sounds like they made the comparison because sauropods already compressed most soil everywhere. So it simplifies it a bit in the title, but it's about exceeding the level of compression already established anyways due to sauropods.
Also the weight over area might become less relevant the deeper you go because it naturally spreads outwards anyways.
> because sauropods already compressed most soil everywhere
That happened long ago that I don't think that you can state that with such certainty about the state of soil today. It makes zero sense. Sauropods lived at the latest 66 million years ago, and quite possibly longer. Unless there is some other link that the article tries to make but I've missed.
