dhw's obsession with 'humans plus food'; current studies (Introduction)

by David Turell , Wednesday, September 13, 2023, 19:14 (228 days ago) @ David Turell

Latest review:

https://www.newscientist.com/article/2391648-humans-use-a-quarter-of-all-the-biomass-cr...

"Humans are now consuming over a quarter of the biomass produced each year by plants on land, leaving too little for wildlife and putting at risk the biosphere on which all life on Earth depends. To keep the planet in a suitable state for civilisation, we should be using no more than a tenth of plant biomass for our food and fuel, researchers say.

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"The researchers have now decided to measure it in terms of how much of the biomass produced by photosynthesis is being appropriated by humans, or is no longer happening, relative to pre-industrial levels. Plant biomass is the basis of food chains, so if we take it, the life that depended on it dies out.

"The study estimates that plants on land produced 56 gigatonnes of biomass a year, as measured by its carbon content, in pre-industrial times, and that through farming, logging, the grazing of domestic animals and so on, people now take 17 gigatonnes per year, or around 30 per cent of pre-industrial levels. Today, plants produce an estimated 66 gigatonnes of biomass a year due to higher carbon dioxide levels, and would produce even more if not for land degradation, meaning that our current consumption sits at around 26 per cent.

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“'I think it is a good, first-order metric,” says Timothy Searchinger at Princeton University. “Anyone claiming we really can acceptably use more of the world’s plant production to meet additional demands created by policy should have the strong burden of proof about how and why that’s OK.”

"Growing demand for food and wood alone means the proportion of biomass we appropriate is likely to increase in the coming decades, says Searchinger. And some proposals for growing crops for energy and capturing the carbon would double our use, he says.

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"So far, however, ocean acidification remains within safe limits, as do the levels of aerosols released into the atmosphere. And while we were once destroying the ozone layer to a dangerous extent, we are now back in the safe operating zone.

"There are interactions between all these nine aspects of the planetary system that we need to take into account to ensure efforts to solve one problem don’t make another worse, says Richardson. “Unfortunately, our legal and political system hasn’t gotten there yet.'”

Comment: this articled shows how we dominate the planet and how we use much of the bush of life for our purposes, food supply and otherwise.