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Yes, minerals follow cycles. But so does hydrogen, nitrogen and carbon and oxygen. It's just that some of those are delivered via air, and some via liquids and some via the soil.

But not fundamentally different.



Nitrogen is an example of a nutrient which is present in air, but which is available through soil for the majority of all plants.

Again: nitrogen fixation is exceedingly energy intensive, and few organisms can achieve this on their own.

Where nitrogen is removed from soil faster than it is replenished, it becomes a critical, growth-determining, nutrient.

Carbon is available in the air, but also comprises a major constituent of topsoils. Though soil carbon itself isn't a plant nutrient, it provides a vital role in supporting plant life in its role in supporting symbiotic life, in managing alkalinity, and in moderating water and nutrient flows.

In many agricultural areas, soil carbon is being depleted at roughly 10x the rate at which it is formed, leading some to term such farming as "topsoil mining". Accumulations over a period of 10,000 years (since the previous ice age) are being degraded over a period of centuries.

Presence in the atmosphere != availability from the atmosphere.




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