And David Laird, of America's Department of Agriculture, showed that biochar even helped the rich soil of America's Midwest by reducing the leaching from it of a number of nutrients, including nitrate, phosphate and potassium.

ECONOMIST: Biochar could enrich soils and cut greenhouse gases as well

It is the movement of potassium (and also sodium) ions that causes the electrical impulses that nerve cells carry including the impulses found in slow-wave sleep.

ECONOMIST: Memory formation