Biodiversity often conjures thoughts of mammals, plants, birds, insects, spiders and molluscs.
Organisms which are not easily distinguished by eye are probably less likely to come to mind. Visible organisms are far more likely to be considered when it comes to biodiversity than the seething masses of microscopic invertebrates, fungi and bacteria which inhabit soils. Topsoil is the most prolific part of healthy and productive terres trial ecosystems. The animals, plants and micro-organisms living in topsoils are both highly numer ous and highly diverse. Figures a thousand-fold higher are not uncommon.