From minuscule microbes to much larger animals, soils are a major reservoir of global biodiversity. Indeed, soils are amongst the most biologically rich habitats on Earth, with greater biodiversity per unit area than that observed aboveground. Soil organisms are not mere inhabitants of the soil but rather part of it, heavily influencing all of its properties. The soil biota includes micro-organisms (e.g., bacteria, fungi, protozoa and nematodes), meso-fauna (e.g., mites and springtails) and macro-fauna (e.g., earthworms and termites). Plant roots and some relatively large mammals (for instance, moles, shrews, mice, gophers and prairie dogs) are also part of the soil biodiversity and undergo uncountable interactions with other soil elements.
FUN FACT: There are more organisms in a handful of healthy soil than there are people on the planet.
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