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Comment by supermatt | Hacker News Reader

They cover exactly this in the article.

The main take is "while surface contact stresses remained nearly constant over the course of modern mechanization, subsoil stresses have propagated into deeper soil layers and now exceed safe mechanical limits for soil ecological functioning".

i.e. they state that the stresses propagate deeper into the soil, regardless of the pressure imparted on the surface.

I dont understand it exactly, but thats what they are saying. I guess its something to do with the increased overall mass being supported by and compressing the underlying soil layers, rather than the (relatively) shallow sub-surface compaction we are usually concerned about.

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Let's say you have a load of 1000 kg on a 1 square meter steel plate on a field. What is the compression 1 meter underground directly below? Less than at the surface. What about compression 1 meter underground and 0.5 meters to the side from the center, ie below the edge of the plate? Even less. And 1 meter to the side, even than that. The load spreads underground. From a small point load, it dilutes fast with depth.

What if you add a similar load directly adjacent to the previous one. Pressure is same but area is added. What is the compression 1 meter underground, at the border between the plates. It's more than in the previous case, since both loads now contribute to it.

So there is a sort of load pyramid that has to form underground to support each point load. And the more point loads you add in a grid, the deeper you go, the pyramid overlap more together. So with constant pressure, the wider area you have, the more there is stress deeper down, and the worse the effect gets with distance.

And it's exactly this part that might elude the "Farmers typically know everything" argument.

I sat around with a group of farmers for years, listening to them tell me that they knew what was best to produce on their land profitably.

Much of their formerly-arable land became un-arable and is today made entirely of sprawling tract homes.

I think thats only a minority of cases where land grows arid and is sold and this arid land is also valuable enough where homes can be built and immediately sold. I've lived in areas on the suburban/rural boundary and its not really like that. The farms are very productive, its just a suburban tract with homes starting at 400k makes a lot more money than a soybean harvest so when a developer comes a knocking farms are eager to sell. The children don't want to be farmers like their parents, they want capital for investment in other ventures and are happy to exit the farm business. Around these new housing tracts fields are still being plowed and harvested because the soil is still productive.

Plus with modern agriculture its hard to get arid land unless you are broke and cant afford fertilizer. Plants need nitrogen, phosphorus, and potassium. they will grow in a cup with some inorganic gravel or on a pile of rusty screws or in some pocket lint if you put these three things in water.

Is that because they didn't know what they were doing or because they saw the writing on the wall and planned their exit?

Low margin industries tend to have a lot of things that are done "wrong" by the calculations of the clipboard warriors that dominate online discourse because said calculations tend to assume constants for things that should are variable (like the regulatory situation, state of technology in an industry or rate of progression therof) and assume amortization timelines that are unrealistic. When your margin is razor thin it often makes the most sense to do things in a manner that's non-optimal on paper but yields guaranteed returns today. Do that every day and you stay in business. You might make less money in the long run but you aren't taking on risky capital investments or boxing yourself into a risky corner with inflexible business practices.

There are two metal recycling yards local to me.

One is part of a chain, run by a subsidiary of a public company. All they do is scrap metal and they are highly efficient at it. Things are clean and run by the book. The facilities are orderly. The machines are new. You can't scrap a car, a street sign, or anything else that's suspect without giving them all sorts of ID. On paper, they do everything right.

The other one is a 150yo family own business. They do scrap metal but have a handful of other income streams using the same facility (everything is for sale, basically). I don't think they have a single tool or piece of equipment that was made this century. The facility is always overflowing with piles of various materials that come and go in no apparent order. Their workplace safety is fine, but absolutely rife with tiny things they could get fined for. They pay their employees crap and make up for it with perks (free lunch every day, free fuel oil in the winter, can use company trucks and facilities for personal projects with permission, etc). I'm pretty sure you could scrap a stolen cop car there if you brought it in the same day that the full train cars of processed material go out. On paper all this is wrong. The clipboard warriors would have a field day making it "better"

Guess who weathered the pandemic with nary a slowdown and guess who couldn't retain staff or keep their machines running and cut back hours?

What builds the resiliency in the latter compared to the former?

If it's "turning a blind eye to regulations" that leads to follow-up questions. Is the intent of the regulations that are not appropriate? (i.e., the requirements are wrong?) Or is it that the former is inefficient about implementing the requirement? (i.e., the process is bad). Both of those have fixes that are outside of the dichotomy proposed in your post.

So the answer is exploiting workers better and criminal activity?

The by the book business isn't hiring young people and teaching them how to drive heavy equipment. If their employees felt exploited they'd have problems retaining them.

I think their employees care more about the perks and the fairly laid back work environment than they care about all the fire extinguishers on the property having an up to date tag. I know I did back when I worked those kinds of jobs.

>fire extinguishers on the property having an up to date tag. I know I did back when I worked those kinds of jobs.

This is a problem with how you're thinking about low probability events. Yes, rules only matter when the low probability event occurs. Do you, for example, not care about up-to-date A&P logs on the aircraft you fly in as well?

I'll be the first to admit that regulations can go beyond what should be considered an acceptable risk, but we have to at least acknowledge the risk they are meant to mitigate before determining if it's a reasonable regulation. That often involves understanding the consequences of low probability events, something we're usually not good at thinking about very well on a day-to-day basis.

> If their employees felt exploited they'd have problems retaining them.

That is not usually true. Lots and lots of people feel exploited by their employers, yet stay in their jobs. Generally, they have financial obligations, need money and benefits, and jobs aren't so easy to replace.

The family scrap yard is hiring able bodied young men and training them to drive heavy equipment (which they then presumably slap on their resumes). I know they get free lunch and (used/questionable) fuel oil/diesel because I've discussed it with an employee (last July/August or thereabouts). Based on the demeanor of everyone there it seems like a great place to work if you don't mind working outside and a fair amount of physical labor. I don't know what they're paid but all things considered it's probably crap. They wouldn't be hiring highschoolers if the pay was good. Considering how permanent some of their employees have been over the years despite being at an age where one is typically "leveling up" quickly.

I feel very comfortable saying they're not exploited.

I don't have the same visibility into the "corporate" yard because I only go there when I have to (they are only closed Sundays and federal holidays) and they have organized their workflow to keep their customers at arms length.

What do you conclude? How does one person's perception of one example impact the overall issue?

> Based on the demeanor of everyone there it seems like a great place to work

If you mean it is your family scrapyard, I will suggest that many employers have formed that impression - often mistakenly (myself included!). I've heard it many times. My favorite was someone who told me how people loved working there and they didn't have the absurdities so common in business. Then we were walking around the cubicals, and it was observed how many Dilbert cartoons were posted.

I meant it is a family business, not my family business. Like their website has a picture of their ancestor hauling a boiler on a cart pulled by a team of oxen and it's currently run by two brothers of the same last name and the same name as the business (so I think it's a safe bet it's still in the same family). The point was to contrast it with BigCo that has MBAs writing the rules and shareholders it's accountable to.

I do a substantial amount of business with that yard (and less of the corporate one, because they won't sell material and are generally way higher friction to do business with) and it looks like a very fine place to work. But this is also coming from someone who has worked in adjacent low margin industries so I have no delusions of ping pong tables in the break room.

To reiterate what I said before, they're taking young able bodied men who are willing to do physical labor (this is a demographic that can basically find new jobs at will, you can't really trap them in a shit job) and teaching them marketable skill. The fact that those employees don't just turn around and get a different job with that skill says something about the value proposition of working there.

Is it really so unbelievable to you that a business can not follow the letter of the law and not treat people like crap at the same time?

I find it completely believable, and I suspect that such practices make up some kind of norm for generational family businesses. I've known many California restaurateurs that behave this way.

short answer is yes, exploiting workers and "defining your activity as legal" whether it is or not.. that is what wins in a highly competitive field.

source: electronics recycling reformer, crushed

There were a bunch of famous "scientific agriculture" disasters in the 20th century caused by simplifying assumptions being too simple.

The pendulum of worst or best practice swings both ways and it's difficult to adjudicate without a ton of local context.

...today made entirely of sprawling tract homes.

Farms fail all the time for a variety of reasons, but even successful farms can be less valuable than suburban residential subdivisions. If the farms in question were further from the city, better farmers would buy/rent them and the land would be productive again.

If the farms in question were further from the city, better farmers would buy/rent them and the land would be productive again.

1. You are assuming "better farms" have the capital and will available to purchase the land.

2. Just because a competent farmer purchases the land does not make the land arable. It could take decades to undo the damage from improperly cared for land.

I am assuming a functioning market for farmland. As I have observed over several decades, and my father and grandfather observed for much longer, the market for farmland is brutally efficient. (Insufficiently-regulated monopsonies arrange society so that their inputs are as cheap as possible.) Lots of rural land lies fallow, and much of that has ruined some poor farmer who tried to grow or graze ground that wouldn't pay him back. My point is just that while we can draw that conclusion about empty fallow ground, we can't draw it about ground that currently sees more remunerative use than farming.

I don't think we can really know anything for sure about point 2 for hypothetical internet discussion agricultural ground. It is probably true that some land has been so damaged, but it is also possible for farmer B to have better results than farmer A on the same land. This is possible even if they are in some sense equally skilled and capitalized. It doesn't rain the same every year...

A competent farmer isn't going to be purchasing useless land.

Why not? Information asymmetry is hard to overcome sometimes. Someone might attempt due diligence but still get burned.

When someone wants to sell a field the real estate agent will ask for copies of the forms you submitted for government insurance, and other forms of proof of that it yielded. you don't have to give this, but it is a red flag to most farmers (not all farms collect this data, they are not worth as much). Giving incorrect information is fraud.

Of course there is always information asymmetry, but farm buyers are aware of it. In most cases the buyer already lives in the area, so they know just be driving by over the years what really happens.

He may also just be working the land of let's say Bill gates and not care much for it's longterm potential. I feel like a lot of us in this thread are just throwing guesses out there.

One of the problems goes back to the reason cities are where they are to begin with. People settled where the farming was best. More people came to join them, the farms became settlements, the settlements towns, and the towns cities. Now all our best land has been paved and farmers are out trying to grow stuff on land that previous generations passed over as not sufficient.

Cities cannot be supported by the farms nearby and must be located near an easy place to ship goods. That was water for most of human history, until the train happened.

Small towns happen all over because of farming reasons, but even then access to trade was a consideration, but only secondary to close to farms. (which is to say if there was good farm land far from any way to trade there will still be a town someplace - you see this more with mines as mineral often are in places that are difficult to get to by trade, while farm countries implies enough water which implies rivers)

At the limit (infinitely wide load), the max sum somewhere in the middle is just going to be the point load at the surface (plus the weight of the dirt). The load you've described isn't an infinite motion machine.

I guess you're saying constant pressure x wider = more weight? So is GP, but the other way around: more weight divided by more width keeps pressure constant.

I'm not going to try doing the math, but the deeper you go, the more the pressure will be dominated by the weight of the soil above.

>So there is a sort of load pyramid that has to form underground to support each point load. And the more point loads you add in a grid, the deeper you go, the pyramid overlap more together. So with constant pressure, the wider area you have, the more there is stress deeper down, and the worse the effect gets with distance.

This only works in the land of spherical cows.

In reality the pressure is never going to be higher than what it is at the contact patch and while a much wider area is bearing the load friction between particles and height of overburden dominate.

If what you are proposing was true many sorts of construction projects would be much simpler

Completely anecdotal case in point: I live on what used to be a farm. Last year was the first where the well below the house did not carry any water despite moderate rain throughout the year. Instead, heavy rainfall in the last days carried away the top soil layers and washed them off the fields and onto streets and playgrounds.

To me, the explanation that lower layers have been compacted and now block the water seem pretty reasonable.

>To me, the explanation that lower layers have been compacted and now block the water seem pretty reasonable.

The simpler and more likely explanation is that you have a clay or otherwise mostly impermeable substrate.

In fact you SHOULD have a layer of clay between the surface and the ground water you are drinking. You don't want a fast path between surface contamination and your well water.

You want a compromise. You need water to get to the well somehow. It needs to get there fast enough to replace what you use, but not so fast that it isn't filtered first.

While it’s better to avoid it in the first place, farmers have long dealt with subsurface compaction using an implement called a subsoiler, which breaks up the compaction and restores normal drainage.

The article didn’t address that, but did speculate about the ecological intentionalities of sauropods. I suggest the authors do more field work, preferably with a horse and a moldboard plow.

Recently I read an article in which someone pointed out that while compaction in the root zone can be mitigated by better management practices, compaction at the bottom or below this are will remain until the next glaciation period.

That is very, very bad. Practically our only option at that point is to build soil up which is not something modern farming remembers how to do.

Where can one find the practice of building up the soil?

Is it a “lost-art” due to introduction of fertilizers?

Tillage combined with fertilizer. Tilling fluffs up the soil temporarily, but it can and often does compact down harder than it was before.

Organic farming started down this path, but semantic diffusion killed that, and the mantle was taken up by the no-till and permaculture people, after their own fashions.

The question of whether animals help or hinder is still a bit of an open one, but there is some evidence that in the wild, herd grazing was a net benefit to prairie health specifically because predator pressure keeps the herd moving. We see a similar thing in forest settings. In areas where wolves have been removed, the deer end up damaging the trees.

A number of farmers have been working on rotation grazing strategies, typically using movable electric fences and short intervals between moving the animals. Joel Salatin and Gabe Brown are two people you can find on youtube (and in Gabe's case, at the book store). IMO Gabe's videos have more information, while Joel's a better salesman.

Edit to add: There's also controlled fires, but that's a far tougher sell in this day and age.

You can contact your local ag university. Building soil up is hard, if you are building a mm of soil every few years you are doing great - good luck measuring that.

Other posters have mentioned no-till: it takes about 7 years from the time you decide to go no-till until the time when your land yields as much as equivalent land that has been tilled all along (assuming all else is the same), but after those 7 years no-till yields better than tilling the land. Thus the question is are you willing to make that investment.

Search for “regenerative agriculture” and “permaculture“. It’s not necessarily something we “lost”. While some ancient farming techniques can be regenerative, exploitative practices have been part of agriculture since its inception. In its modern form, industrialized agriculture is essentially strip mining.

Symbiotic relationships take things from the other party, but they are repaid in kind.

We can't live without eating things, and in our turn we are eaten. That's life. 'Extract' can have a connotation similar to 'exploit' and if you hear anyone talking about 'extractive' in reference to the environment, that's usually the connotation the speaker is after. But 'exploit' and 'extract' can also mean something closer to 'leverage', which I think is generally the sense one associates with a symbiotic relationship.

My read on this is that humans get a bad rap because so much of recorded history and popular culture is colonial, and the most efficient conquerors also conquered the land, not just the people. Annual plants transport well, and transplant well. A civilization that survives on walnuts or figs or dates or fish can take land from another tribe and thrive immediately, because neighboring tribes have pretty similar diets and agriculture. But conquering another civilization? More efficient if you can bring your agriculture with you, destroy theirs, and replace it with yours. Even if you leave, that scar will last for generations.

Conquest is less effective if you have to assimilate first. Which is not to say that it doesn't work (eg, the Americas) but your competition might get there first. The people with attachment to place were better stewards, but that attachment makes you vulnerable in other ways.

Look up "permaculture" and "regenerative agriculture" https://permies.com/f/120/soil https://www.thesurvivalpodcast.com/?s=soil

Regenerative agriculture is the future of farming and is the critical approach to a sustainable food system.

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 agree that it's a pretty shaky extrapolation they're making here, just trying to explain the reasoning.

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.

> Chris Pratt using a team of sauropods to farm in the next Jurassic Park movie.

If that's not in Randall Monroe's What If, I assume it must be in the upcoming sequel?

> Coming soon: Chris Pratt using a team of sauropods to farm in the next Jurassic Park movie.

The Good Dinosaur (2015) - Argo and his family worked the farm like champs. No “T wrecks” there!

Simpsons^WFlintstones did it

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.

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