Devonian era

What does it matter, as long as the crops keep coming in The 1993 floods in Iowa, USA, uncovered fossils from the Devonian era. Soil that was formed at a time when the inhabitants of Earth were still mostly fishes has been eroded away forever as a result of agricultural practices that commenced in the 1870s. When soil disappears into the sea it cannot be replaced. Chemical fertilisers are only effective when there is some topsoil which they can enhance. Once that topsoil is gone, there are rapidly diminishing returns and the cost of producing foods on barren sands and clays fertilised with artificial... 

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