[account_b]

> We survive on stored energy borrowed from the past.

It's worse than that: We fully rely on borrowed time!

Natural geological cycles to restore surface phosphorus span many thousands of years. Our current agriculture (food production) critically depends on mineral phosphorus, which may be exhausted in just four or five decades. And we retain none of that, but flush our soils into the oceans (partially through the toilet, literally). No phosphorus, no food. I wish everybody knew about peak phosphorus. (It's also a geopolitical near future issue as almost all phosphate rock is located in Morocco...)

> We also need to develop tech (weather technique or technology) to reconstitute waste and refuse into the inputs for our food, buildings, transportation, etc.

Yes! We also need to collect and recycle human and livestock feces and urine to prevent mineral loss. Those cannot leak from the ecosystems anymore - madness!

Honestly, I think it's possible humanity will barely not make it, comically, because no one wants to lobby for collecting people's shit, while everything else goes full Star Trek.

[jnmandal]

> no one wants to lobby for collecting people's shit, while everything else goes full Star Trek.

Ironically in Star Trek, the food from the replicator is made from human waste or that's what they say in recent seasons anyways.

I am optimistic about the ability for us to recycle human waste despite the lack of popularity though. Most people have no idea what goes on at water/sewage treatment facilities and they don't really care. Even with no regulation or subsidy, it will eventually become profitable to recycle this waste b/c of geopolitical issues like you mentioned.

I'm pretty worried that we wont be able to cut back on consumption though and will end up buried in piles of our own junk.

[korantu]

Does it also mean that using wood at industrial scale is bad idea? Trees need phosphorus too

[account_b]

To add: I want to stress the phosphorus is used by all livings things part.

Plants get phosphorus from soil, animals get it from plants, predators from other animals, and finally microorganisms from our all remains. But it all starts with plants. We cannot grow "low phosphorus" food plants or anything. It's used in ADP and DNA synthesis! Phosphorus sits at the core of life itself. Every living cell on earth depends on what plants can extract from soil.

[account_b]

I can only speculate.

I think wood itself contains little phosphorus, compared to other parts of the plant. The inner rings of a tree are dead cells, a formerly living tissue, which condensed to cellulose and lignin. I assume the plant will not have phosphorus left there substantially. Phosphorus is needed to make ADP and DNA, by all living things, and is used in photosynthesis by plants, too. Quite useless in the middle of the dead wood zone. In woody plants, only the outer layers and leaves are living cells. If you leave those in the forest to rot, you retain some phosphorus.

You could also burn furniture after a century of use for energy and then bring the ash back into the forest to close the cycle, I guess. But that's requires non-toxic ashes - compatible paints and glues, no heavy metal agents and so on.

Either way, you are in competition with agriculture land use for food production. And bio fuels. And bio polymers. And bio... You get the idea.

Tho, if I had to guess, I would say wood probably is not the worst in terms of phosphorus leakage.