Soil 2

Soil is one of the most diverse habitats on Earth. Nowhere in nature are species so densely packed as in soil communities.

For example, a single gramme of soil may contain millions of individuals and several thousand species of bacteria. The complex physical and chemical nature of the soil, with a porous structure, immense surface area and extremely variable supply of organic materials, food, water and chemicals, provides a range of habitats for a multitude of organisms. These range from macro- to micro- levels depending on climate, vegetation and physical and chemical characteristics of a given soil. The species numbers, composition, and diversity in a particular ecosystem depend on many factors including temperature, moisture, acidity, nutrient content and the nature of the organic substrates.

Soil biota includes archaea, bacteria, protists, tardigrades,rotifers, nematodes, acari (mites), collembolans (springtails), worms (enchytraeids and earthworms), macroarthropods (e.g. ants, termites, centipedes, millipedes, woodlice, etc.) and
burrowing mammals. It also includes plant roots, fungi, and lichens. Root exudates attract a variety of organisms that either feed directly on these secretions or graze on the microorganisms concentrated near the roots, giving this busy environment the name ‘rhizosphere’. There are also animals, such as beetle larvae, flies and butterflies, that use the soil as a temporary habitat to
reproduce or to spend their early life stages feeding on different live and dead plant materials until they reach their maturity.Soil communities are so diverse in both size and numbers of species, yet they are still extremely poorly understood and in dire need of further assessment. Research has been limited by their
immense diversity, their small size and the technical challenge of identifying them.

Source - Global Soil Atlas