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Comment by Mistletoe | Hacker News Reader

https://soilsolutions.net/save-the-topsoil/

>According to this display the average depth of topsoil in the year 1850 across Iowa was 14 inches. In 1900 it had decreased to 11.5 inches. After another 50 years it had dropped to 8.5 inches and in the 50 years from 1950 to 2000 it had decreased another 3 inches to 5.5 inches. If our rate of loss has stayed steady over the last 18 years the topsoil depth should now be at 4.5 inches. If this rate continues our topsoil will be depleted by 2093.

It seems we may be aggressively depleting our topsoil like we are our petroleum resources. We could just be in the final era before the plunge for both. I hope we are using what we have left to fix the problem and find new solutions.

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I feel like we're going to end up moving towards hydroponics and the like before/instead of resolving the topsoil problem

Nah we just need to stop growing food for diesel

The distillers grain that is left over from biofuel production is fed to cows and makes up a significant fraction of all cattle feed. If we stopped, that corn would still be planted but beef would get more expensive.

Well, we also need to eat less meat. The American west can sustain vast herds of ruminants in land that is not suitable for farming.

We don't all need to do anything. You can do as you please.

Seems like lower corn prices, higher beef prices, some marginal environmental benefit, and lower fuel prices is kind of reasonable trade off all-told if that was where it netted out.

I think we are rather going to have starvation and collapse.

If you’re just looking at calories the US has a massive surplus of arable land.

It seems likely to me, since topsoil erosion is very hard to avoid when you are trying to farm the land. Creating new topsoil is mostly done by letting old organic material decay, but there's no time for that if you need to plow it up to plant the crops for next season.

Zero-till farming will come to parts of the mid-west in fits and starts as farmers realize that the current methods are unsustainable, in most places there is no need to "plow it up".

In western Canada farming practices involve more crop rotations and less tillage, the net result has been increasing organic matter in many areas. I farm in an area with a surplus of organic matter, and too much can be a problem, so we still engage in a lot of tillage under normal precipitation conditions.

https://agriculture.canada.ca/en/agriculture-and-environment...

What kind of problems do you see with too much organic matter? I really like to garden and often find myself going overboard on mulch and compost and paradoxically seem to notice slower growth sometimes when I use them. I wonder if it is too much organic matter?

I can't speak to the exact circumstances in your garden but too much organic matter can have the effect of "tying up" nutrients in the organic matter in a way that makes them inaccessible to crops - if you grow to large a microbial biome in the organic matter they immobilise nitrogen.. I am not an expert on this so I only understand it in broad strokes.

I am a bit of gardener and my anecdotal advice is - I don't know what sense you are using the word "mulch" here so I am not sure about that but too much compost can be an issue if you are not letting it break down long enough and not incorporating into existing soils well enough. Too much compost will grow wicked-hot radishes, but your leafy greens will be ugly and taste like garbage in my experience. The thing about gardening is it is all small sample sizes.. it ain't science and it is hard to know what's up without a good old fashioned site visit!

As far as I know hydroponics isn’t really feasible for grains like wheat and corn. It’s great for growing salad items like tomatoes and lettuce but those won’t keep us alive as a staple.

https://www.quora.com/Why-isnt-it-common-to-grow-corn-hydrop...

That's not something that would really need to be considered unless you're talking completely apocalyptic, no soil at all.

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