SC Wisconsin | Short answer is no. I agree with you on the mining and transport off the farm topics, but with a couple exceptions; carbon and nitrogen. A primary function of a plant is to fix CO2 and use it. N2 is transformed by nitrogen fixing bacteria and some fungi/algae. Both come from the atmosphere and become part of the plant available nutrient pool. C and N are often limiting components of the soil biota. Cover crops can increase these elements in the soil. How much and whether it is economically feasible - well that's another topic and gets into the soil health discussions. The mineral components are ultimately finite over millennia or sooner depending on the parent material. There ain't no free lunch! |