“Someone says, ‘Soil is just dirt to hold the plant up.’ Would you agree or disagree with this statement?”
I would disagree with this statement. Sure, soil provides anchorage to the plant, but it does much more than just that. Soil also provides the plant with some of the water and oxygen that it needs. It also provides habitat for fungi, burrowing animals, and insects.
One could argue that even with those extra qualities, soil is still essentially just for supporting plant and animal life. BUT, soil is also good for breaking down and recycling raw materials, as well as foundation for engineering projects.
Source: http://umaine.edu/gardening/master-gardeners/manual/soils/soil-and-plant-nutrition/
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