Abstract

The most abundant multicellular organisms in the soil are fungi (although the group also contains unicellular members – yeasts). Fungi are an extremely diverse group of heterotrophic organisms. Most are saprophytic, playing key roles in decomposition and pedogenesis processes. We can add parasitic species, as well as lichens, and photoautotrophic symbiotic associations. Similar to an organization and way of life are mycetozoa and pseudofungi (oomycetes and their relatives). Plants are present in the soil only through their underground organs (roots, rhizomes, bulbs, etc.), but have an essential contribution to the genesis and functioning of soil, once their various underground and aboveground components decompose. Finally, animals are some of the main consumers of soil. Here we may find nematodes, annelids, insects, and other arthropods and some species of vertebrates that use soil as a temporary or permanent living environment.