I want my own small farm, but I think that I want to make food instead of money. It's a different proposition, I suppose.
Also, if that small farm is something you dream about, I strongly suggest actually working on a farm for a while. It is surprisingly not fun. I know "I'm gonna have a farm" is a popular escapist things for many folks in tech - it is for me as well, the fantasy is great :) It's just good to know what that actually means, and then deciding if you really want to do that. (For me, it means I have three plants on my balcony to keep the dream, and skip the full experience because I know I wouldn't enjoy it)
1) How many calories does a human need to survive?
2) How many calories can we squeeze out of an acre of arable land?
3) How many acres of arable land are there?
The first one is pretty much immutable.
The third one is maybe somewhat mutable, but to a very limited extent. We can squabble how much, but let's assume it's fairly immutable. Large changes would need energy amounts that are currently prohibitive.
That leaves calories per acre. And that's where ag-industrial methods had an impact that's absolutely bonkers[1].
As the graph shows, this is not a fixed number - that's why Malthus' predictions ultimately didn't come to pass - but you need ag-industry to squeeze out those numbers. (Without mechanized agriculture, massive production of artificial fertilizer, and Borlaug's dwarf wheat, Earth would have run into massive hunger by the end of the 80s - look for "Green Revolution" for lots of info on that)
And small scale subsistence farming (which is what most folks think of when the say "I want to grow food") cannot utilize all of those techniques.
That's also where the "4 billion" number comes from - we know how many calories/acre non-industrial farming generated, and it was at best enough calories for ~4 billion people. Optimistically.
[1] https://www.researchgate.net/figure/USDA-per-acre-crop-produ...
So, no.
Neither does that explanation account for overconsumption, food waste & spoilage, crop mixes, erosion & desertification, water supply shifts, etc...
It's a very basic upper bound. The number of people who could be fed in the best case.
Maybe because I grew up on a farm and this is returning, but also because I do expect about 4 billion people to die in the coming climate decline? collapse? and would like to leave better more resilient bones (buildings, good soil, lumber trees, good game, maybe some tools, landrace seeds etc), the skeleton of a more sustainable life to those who come after.
Actually, I love farm work. I grew up in the country and did quite a bit of farm work when I was younger. It felt great to be outdoors, and not have the constant massive stress I now have as a knowledge worker with ADHD. But it pays poorly and is hard on your body.
I've both done that, and I sit in an office chair 8 hours a day. Anyone who prefers the latter has a different set of maladaptive personality defects than I do.
> This is likely not an answer. Small-scale sustenance farming is not enough to support humanity at scale.
It's ok. No one really needs to think about that anymore. When fertility rates went sub-replacement, humanity became functionally extinct, at least in those regions. Everyone's planning a future for their species which it no longer has.
> I know "I'm gonna have a farm" is a popular escapist things for many folks in tech - it is for me as well, the fantasy is great
Not a fantasy. I'm a few weeks/months away from buying a combine. I have a particular model in mind (John Deere model 42), but the used market is a little difficult to deal with. I may end up paying a few thousand to have it shipped from out of state (or even Canada), but no one can tell me if it's narrow enough to fit on a flatbed trailer.
I have less of a clear idea about what tractor to pull it with, I really need something up around 100hp, something gen ii probably. A 4230 with a cab sounds nice, but it's like 9 gallons of diesel an hour. I'd grow sunflowers for the fuel, and I'm experimenting with a chloralkali machine for the soda lye (there are places not far away with salt springs, so I'm looking for real estate like that for salt). Currently assembling a larger machine I've got half-designed. Would use butanol instead of methanol.
Not sure I could survive in a place where all I can do and hope for is "a balcony with some houseplants". Sounds soul-crushing.
That is... also a way to look at it.
1) Migration is a thing, so unless total fertility is sub-replacement, "functionally extinct" is a tad bit premature. Turns out that across the world, we're still above replacement rate.
2) Fertility rates do change over time. E.g. the fact of group size temporarily inducing stress-related infertility until a population is below a certain level is well-known and understood. Here's a great experiment on it: https://pubmed.ncbi.nlm.nih.gov/11100725/
It's at least plausible that sub-replacement rates in humans are a similar self-regulation mechanism. I'd suggest that "functionally extinct" is maybe a bit of a premature judgment.
Yeh, the mathematically correct way. There are only about 4-5 generations of humans on the planet at any given point in time. Only the youngest of those can create the next generation. If each generation is getting smaller than the previous because the fertility rate's low, why would you expect population to stabilize?
> Migration is a thing, so unless total fertility is sub-replacement,
Outsourcing your fertility to countries with rapidly declining fertility probably isn't a long term (or short term) fix for the problem.
> "functionally extinct" is a tad bit premature.
In less than 25 years, it will be global. Unless you believe that in a handful of African countries that it will stay above 5 forever, even though it was twice that less than 80 years ago.
> the fact of group size temporarily inducing stress-related infertility until a population is below
So, you believe that all the little girls who exist today, who grow up as only children, who have no aunts or cousins, who see their school teachers childless, all their role models childless... they'll grow up themselves and say "Wow, I want 9 children of my own!"?
I think you're confusing the models here. The moose don't have low fertility, it's as high as ever, but the wolves eat so many offspring, or the food sources so sparse they starve.
In the stress-induced models like Calhoun's mice, population never recovers. The mice become extinct. Even though there's plenty of food, plenty of water, plenty of entertainment. Even after the population crashes, and there's no overcrowding, even then their fertility rates are so low that they just go extinct.
I have no doubt that unless you're in your 60s, you'll one day come to understand that I was correct. This is coming, and nothing other than underwhelming horror at the thought of me being correct explains why you choose to argue about it. HN is filled with people who understand how to predict trends with lines on a chart, and you know or could quickly verify which way fertility numbers are trending. Which direction it is that they can only trend, at this point. "Functionally extinct" is indeed the perfectly correct term for this. It's what you call a species that still has living extant specimens, but for which there is no realistic way for the species to survive in the long term. That's humans.
But, crucially, these small farms could not grow the plants they chose to grow, instead they would have to grow an assortment of diverse species or cultivars, for no other reason than to support a living diversity. 99.9% of the plants you'd be growing would be plants that people decided a long time ago that they didn't want to eat, or use for any other purpose, because there was a better alternative.
Ignore the money part. That was me saying that, if consumption/purchasing of plants is more or less stable, then if you introduce 200,000 varieties of plants into the world, every plant would be sold a lot less. It would be more or less impossible to make a living as a farmer.
It's called a https://en.wikipedia.org/wiki/Plant_nursery and many specialized in native and obscure cultivars.