Last modified on Fri 16 Apr 2021 01.01 EDT Hidden under our feet is a miniature landscape made up of tunnels, caves and decaying matter. Soil is where a quarter of the species on our planet are believed to live and in this dark, quiet, damp world, death feeds life. Rotting leaves, fruits, plants and organisms are folded into the soil and burped out as something new. Good soil structure provides many nooks and crannies that house organisms, which, in turn, create an environment that suits them, directly altering â and improving â the structure of soil. Like a collective of tiny chemists, they keep soils healthy and productive by passing nutrients between them, either by collaborating or killing each other.