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Do they? I mean minerals of course must come from the soil, but aren't vitamins and the macro-nutrients created in the plant itself? And can heavy farming reall

Do they? I mean minerals of course must come from the soil, but aren't vitamins and the macro-nutrients created in the plant itself? And can heavy farming really drain so much of the mineral content from the soil that future crops grown there will have fewer minerals? I know crops can drain nitrogen and other gases from the soil, but that's what fertilizer and tilling are for.

gascan 9y ago
That's an emphatic "yes". Standard fertilizer is NPK- Nitrogen, Phosphorous, Potassium. If it was not possible to drain all of the (bioavaliable) P & K, ask yourself, why would anyone ever need to use NPK?
- openasocket 9y ago
  Thanks! I did a little bit more reading on the subject. It seems like P and K are the two main minerals provided by fertilizer, but there's also zinc, copper, iron, manganese, and, oddly, molybdenum. And some plants apparently also deplete other elements, like sugar beets use a lot of boron. 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.
  - gascan 9y ago
    The rotation/organic/etc argument is that properly managed soil & fields sustain their yields indefinitely with significantly less fertilizer, water, etc input, whereas the traditional industrial ag model achieves higher yields initially but the soil quality & yields decline rapidly & require ever more fertilizer, water, etc input. In short, the first model has lower peak yields but is more sustainable; the second has higher peak yields but "uses up" the land, and within only 1-3 decades at that. 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.
tialaramex 9y ago
With Nitrogen what's going on is that there's a tiny bacterium using some seriously advanced chemistry to attach Nitrogen gas (ubiquitous in our air) to Hydrogen (from water which is also ubiquitous) to make ammonia‡, which can then easily be used to make organic molecules. Plants which have a symbiotic relationship with these bacteria are readily available and can be grown to "fix" nitrogen into your soil. ‡ 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.
itomato 9y ago
Soil is not sterile. The microbes at work synthesizing nutrients from those chemical fertilzers and raw minerals, making them bio-available and aiding uptake are vital. http://www.pnas.org/content/114/44/11574 http://www.pnas.org/content/114/44/11574

gascan 9y ago

That's an emphatic "yes". Standard fertilizer is NPK- Nitrogen, Phosphorous, Potassium. If it was not possible to drain all of the (bioavaliable) P & K, ask yourself, why would anyone ever need to use NPK?

openasocket 9y ago
Thanks! I did a little bit more reading on the subject. It seems like P and K are the two main minerals provided by fertilizer, but there's also zinc, copper, iron, manganese, and, oddly, molybdenum. And some plants apparently also deplete other elements, like sugar beets use a lot of boron. 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.
- gascan 9y ago
  The rotation/organic/etc argument is that properly managed soil & fields sustain their yields indefinitely with significantly less fertilizer, water, etc input, whereas the traditional industrial ag model achieves higher yields initially but the soil quality & yields decline rapidly & require ever more fertilizer, water, etc input. In short, the first model has lower peak yields but is more sustainable; the second has higher peak yields but "uses up" the land, and within only 1-3 decades at that. 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.

tialaramex 9y ago

With Nitrogen what's going on is that there's a tiny bacterium using some seriously advanced chemistry to attach Nitrogen gas (ubiquitous in our air) to Hydrogen (from water which is also ubiquitous) to make ammonia‡, which can then easily be used to make organic molecules. Plants which have a symbiotic relationship with these bacteria are readily available and can be grown to "fix" nitrogen into your soil. ‡ 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.

itomato 9y ago

Soil is not sterile. The microbes at work synthesizing nutrients from those chemical fertilzers and raw minerals, making them bio-available and aiding uptake are vital. http://www.pnas.org/content/114/44/11574 http://www.pnas.org/content/114/44/11574