Soil is the major habitat for organisms (flora and fauna as well as microorganisms). A broad diversity is essential for the stability and resilience of an ecosystem. This is particularly important with regard to climatic extremes which may put a soil under pressure. The so-called “carrying capacity” is linked to diversity. The diversity is important on different levels: (i) Diversity of ecosystems, i.e. different habitats, (ii) diversity of organisms, (iii) diversity of genes (from an agricultural point of view important for future plant breeding), (iv) diversity of functions (e,g, functions can substitute each other which enhances the stability of the ecosystem.