
Half of the biodiversity in forests is unseen because it lives belowground. These organisms are miniscule in size, but their importance to the ecosystem is enormous.
In a single teaspoon of forest soil there are thousands of species and billions of individual organisms. These include microorganisms such as bacteria and archaea, soil animals like the microscopic protozoa, nematodes, tardigrades, collembolan and mites, and larger fauna such as millipedes, centipedes and worms.