Phosphorus would be better example. Even if you take only part of organic matter away, as long as it's faster than phosphorus availability from rock weathering,

Phosphorus would be better example. Even if you take only part of organic matter away, as long as it's faster than phosphorus availability from rock weathering, there's going to be a reckoning eventually. Sure it can be added via fertilizer...if we'll be able to source such a quantity. It's not very abundant.