The soil horizon beneath the A or E horizons, where clay, iron, or organic matter often accumulate. It typically has distinct structure and color differences from upper layers.
Microscopic single-celled organisms that drive many soil processes, including decomposition and nutrient cycling. They include cyanobacteria and actinomycetes.
A soil food web where bacterial biomass outweighs fungal biomass, often in disturbed or fertile soils.
The percentage of a soil’s cation exchange sites occupied by basic cations such as calcium, magnesium, potassium, and sodium.
The initial condition of soil against which future measurements or monitoring results are compared.
The ability of soil to support weight, such as heavy machinery, without collapsing or compacting. Strongly affected by soil moisture.
The solid rock beneath the soil profile, which may be exposed at the surface or lie under unconsolidated materials.
A representative soil type that serves as a reference for research, classification, or agricultural practices.
The variety of life forms in a particular area, including plants, animals, and microorganisms.
The role of soils in supporting diverse organisms and ecological interactions, contributing to ecosystem services and natural capital.
