There is also the small problem that we soon won't be able to. Peak phosphorus is a thing, and while it won't affect us in the west much, it will lead to famine.
Well, since 70s we learned a lot about the soil ecology.
We can talk about N, which plant can't access directly. Roots have to produce different substances that are eaten by various organism in soil and they then break the N into form that could be accessed by plant.
Commercial fertilisers give the plant N in form that could be consumed directly, so the plant is not motivated in producing compounds for rest of soil organisms. Once they are all dead the plant is reliant to those fertilisers.
So this is, simplified version, of how plants gets N, but similar situations are with other compounds, especially K, which kinda change the structure of soil and basically lock it for other type of living organisms and nutrients.
That's a gross oversimplification of the issue. By using mineral fertilizer you add a big load of nitrates to the soil at once instead of slowly decomposing nitrates bound in organic compounds. The plants can't absorb this ok at once. This leads to a run-off into the oceans and ground-water, and also polluted the atmosphere with nitrous oxide. Finally the soil biology is negatively impacted by this.
If you consider phosphor mineral fertilizer you get the problem that you add heavy metals like cadmium and uranium to soil.
The issue with injecting nitrogen in the soil isn't about the nitrogen's source, but it's impact on the carbon content of the soil.
>There has been some research showing that these high nitrogen inputs are destroying the carbon in the soil. Because the microbes use up the extra nitrogen and then they really tear the carbon out, creating lots of CO2, rather than sequestering it in the soil. So there is evidence that excessive nitrogen actually causes more carbon to leave the system. Whereas we need more carbon in the soil rather than less.
this just isn't true, and fertilizers work really well.
"With average crop yields remaining at the 1900 level the crop harvest in the year 2000 would have required nearly four times more land and the cultivated area would have claimed nearly half of all ice-free continents, rather than under 15% of the total land area that is required today."
https://en.wikipedia.org/wiki/Haber_process#Economic_and_env...
Yes, fertilizers works very well in the same way junk food works very well if the only thing you want to measure is the amount of fat human could produce.
"In the face of a proposed 21 percent cut in the USDA’s budget by the Trump administration, Haney also stressed the importance of unbiased, government studies in a field where research is often dominated by the very corporations that benefit from overuse of fertilizers and chemicals."
It's quite interesting that while the above sentence has two very strong conflicts of interest, only the corporations' conflict is noted by the author.
https://en.m.wikipedia.org/wiki/Peak_phosphorus
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