Critical Zone Services: Expanding Context, Constraints, and Currency beyond Ecosystem Services | Crops, Soils, Agronomy News | CALS in the News |

Humans derive many ecological, economical, water, and nutritional benefits from the critical zone (CZ), which is defined by the National Research Council (2001) as the area extending from the top of the vegetation canopy to the vertical depth of the freely moving groundwater. It is very important to note that soil in the CZ takes hundreds of thousands of year to form, whereas erosion or human disturbance can wash it away or otherwise reduce the productive nature of this important feature of the biosphere.