The most impactful elements of modern agriculture are entirely animal-based. Full-stop.
You in fact rightfully but incompletely recognize : artificial fertilizers (for giant mono-crop fields of soybeans to feed to cows and pigs [0]), replacing forests (to clear room for soybean fields and pasture for cows and pigs [1][2]), and runoff of these fertilizers and manure into waterways. The parent comment is right - if we want to fix these problems, we must stop killing and eating animals at such an industrial and horrendous scale.
You in fact rightfully but incompletely recognize : artificial fertilizers (for giant mono-crop fields of soybeans to feed to cows and pigs [0]), replacing forests (to clear room for soybean fields and pasture for cows and pigs [1][2]), and runoff of these fertilizers and manure into waterways. The parent comment is right - if we want to fix these problems, we must stop killing and eating animals at such an industrial and horrendous scale.
0. https://www.ucs.org/about/news/extent-emissions-created-mass...
1. https://ourworldindata.org/drivers-of-deforestation
2. https://gfw.global/39qbPdC
3. https://ourworldindata.org/global-land-for-agriculture