The microbial loop concept as used in terrestrial soil ecology studies.

Components and processes in the aquatic microbial loop are compared with the composition and functioning of the soil microbial loop. Relative to their bacterial and/or fungal food sources, many of the soil water-film fauna (e.g., protozoa, nematodes) are conspicuous by low biomasses and high turnover rates of carbon and mineral nutrients. Comparisons with production and turnover rates of aerial (pore-inhabiting) fauna are made, and the highly patchy nature of soil microhabitats is shown to be similar to that of aquatic (marine) habitats.