[lazide]

This entire post is absurd.

There is no magic ‘carrying capacity’ number, except perhaps a couple hundred million before mechanized society and fossil fuels. And those times were far from pretty.

And synthetic fixed nitrogen is not isotopically different in some meaningful way. And even if it was, that isn’t damaging anything.

[unearth3d]

Synth. N results in plant cells (specifj ally sieve plates) being weaker, for instance roof thatching from urea-fertilised crops lasts a tenth of the time of organic. Synth N's different isotope form is also a key way of determining organic food certification.

[lazide]

lulz. Manure causes way wider isotopic variaion than synthetic fertilizer (and always has). https://wwwrcamnl.wr.usgs.gov/isoig/period/n_iig.html

“ Soil-derived nitrate and fertilizer nitrate usually have overlapping compositions, preventing their separation using 15N alone.”