sure, we can make them grow well in a lab. but a natural system is so much simpler and elegant
If you only grow plants with externally-sourced nutrients, that is neither sustainable nor permaculture.
Though it may be more efficient to grow without soil; soil depletion isn't prevented by production processes that do not generate topsoil.
JADAM is a system developed by a chemicals engineer given what is observed to work in JNF/KNF. https://news.ycombinator.com/item?id=38527264
Where do soil amendments come from, and what would deplete those stocks (with consideration for soil depletion)?
(Also, there are extremely efficient ammonia/nitrogen fertilizer generators, but still then the algae due to runoff problem. FWIU we should we asks ng farmers to Please produce granulated fertilizer instead of liquid.)
The new biofuel subsidies require no-till farming practices; which other countries are further along at implementing (in or to prevent or reverse soil depletion).
Tilling turns topsoil to dirt due to loss of moisture, oxidation, and solar radiation.
Three Sisters: Corn, Beans, Squash: https://en.wikipedia.org/wiki/Three_Sisters_(agriculture)
Companion planting: https://en.wikipedia.org/wiki/Companion_planting
Nitrogen fixation: https://en.wikipedia.org/wiki/Nitrogen_fixation
> "Discovery of nitrogen-fixing corn variety could reduce need for added fertilizer" (2018) https://news.ycombinator.com/item?id=17721741
> The new biofuel subsidies require no-till farming practices
This actually depletes soil of nitrogen!
A plausible hypothesis: tilling destroys the bacteria that get nitrogen to plant roots.
Isn't runoff erision the primary preventable source of nitrogen depletion?
FWIU residue mulch initially absorbs atmospheric nitrogen instead of the soil absorbing it, but that residue and its additional nitrogen eventually decays into the soil.
I have heard that it takes something like five years to successfully completely transform acreage with no-till; and then it's relatively soft and easily plantable and not impacted, so it absorbs and holds water.
No-till farmers are not lacking soil samples.
What would be a good test of total change in soil nitrogen content (and runoff) given no-till and legacy farming practices?
With pressure-injection seeders and laser weeders, how many fewer chemicals are necessary for pro farming?
Farming is hard, unpredictable (prone to disasters/famine/plagues), and prone to all sorts of problems with soil, weather, etc.
The reason modern fertilizer and pesticides are used so widely is they make that fundamentally extremely difficult process easier and more predictable.