
This is why cities can’t grow all their own food - ph0rque
http://conservationmagazine.org/2016/01/this-is-why-cities-cant-grow-all-their-own-food/
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Grishnakh
I think they missed some stuff: rooftops (esp. of large buildings) are usable
for growing plants, and the big factor they missed is vertical farming, which
is just starting to be explored.

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Rhapso
Honestly, I think the take-away from this is not that we should not try to
make our settlements self sufficient, but rather our cities are way too
population dense to survive in the long term.

Maybe the population density at which all food can be grown reasonably locally
is where we should max out?

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tryitnow
Why are they too population dense?

Broadly speaking there are usually advantages to economic specialization.

It seems to make sense that cities specialize in being places where humans
live and work since there are advantages to being close to other humans.

And rural areas specialize in being places where food for humans is grown.

It seems like the solution is to free up more farmland near cities by reducing
the suburbs and folding their populations into cities, making cities denser.

So I could see the argument that maybe the problem is that our cities are not
sufficiently dense to prosper in the long term.

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Rhapso
My opinion is generally is founded on a radically different premise than most
economic models. I think we should be optimizing the arrangement of our people
and society for fault tolerance. In the long-view, cities are deathtraps (I
say as somebody who loves to live in one). Failures in any number of
centralized systems could result in hundreds of thousands of deaths.

A "fault-tolerant" society would look more like mostly self-sufficient
communities of around 200 people with independent basic infrastructure: power,
water, sewer, emergency services and food. These communities could be packed
fairly tightly, but nowhere near as dense as modern cities. Independent
critical infrastructures is required for any sort of real fault tolerance.

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Terr_
I think it underscores how much we (and other animals at high tropic-levels)
directly or indirectly rely on extracting energy from other species within a
large area.

