Industrial farming optimizes for efficiency and rarely goes to the lengths necessary for maintaining rich soil and healthy environment for the plants.
You may want to look up biological farming.
I wonder about the environmental tradeoffs between using crop rotation vs. fertilizer for some of the micronutrients. On the one hand, there's an environmental cost to creating fertilizer, there's dangers of over-fertilizing, runoff, etc. But a crop rotation system means some fields will have to lie barren, or with less valuable crops, and potentially with lower yields, which means you need more farmland to grow the same amount of food, which means clearing more forests. Of course, I'm not even a novice in this subject, I'm sure there's a lot I'm missing.
A related example of the consequences of "using up" land can be seen with bananas. In that case, a deadly banana fungus is slowly, inexorably spread through the soil by human activity. Eventually a plot of land becomes unusable for growing bananas due to the spread of the fungus. No matter, the banana company just cuts down more rainforest for new land and abandons the old plot. Later, in perhaps ten years, the new plot will be contaminated & unusable, and the cycle continues.
‡ What's advanced here is not spending a ludicrous amount of energy, we can fix nitrogen, but we use a factory with high temperature and pressure to make the conversion work, the bacterium does it happily inside a peanut plant.
The microbes at work synthesizing nutrients from those chemical fertilzers and raw minerals, making them bio-available and aiding uptake are vital.
As I understand it (coming from rural Ontario—5th largest agri-region), farms and especially large farms (around there) are required to—or at least make it a habit of best practice—strategically rotate crops every n seasons to allow the soil to replenish.
It's not so simple as that, but I'm no biologist or farmer—just a former country boy. Maybe somebody more knowledgeable could enlighten or expand.
But what concerns me most about modern farming is the separation of animal production from plant production. I'm the sixth generation on my family's farm, and I'm the first generation to not also have animals. I do worry about the long-term effects of that. When I get into ground away from the historic family farm, that hasn't seen animals for decades or longer, you really notice a difference in the quality of soil vs. the home farm that has had animals for centuries as part of that crop rotation. Rotation is important, but rotation with animals seems to give the very best results. It is the model that agriculture grew up on and something we have lost (somewhat) recently.
With that said, I think fertilizer is a big part of it. While we always used some synthetic fertilizer in my lifetime, the needs are greater now. Another thought is a greater opportunity to diversify the crops grown in the rotation. Things that humans can't eat, but animals can. There seems to be a difference in growing food for people for a few years and then growing food for animals for a few years over trying to grow food for people every year, where the choices are much more limited.
But this is speculation on my part.
Again from a naive standpoint, it sounds like that's an issue that fertilization is supposed to supplant. Are there other observations outside of that you could point to?
I'm asking out of sincere curiosity at this point. Also what part of Ontario, if you don't mind me asking?
Not saying there is a fallow, but that sugar beets take a lot of nutrients from the land, at least in this area.
Sorry for the lack of proper terminology, agriculture is not my primary occupation.