Soil is defined in terms of dynamic circulation patterns of water, air and minerals driven by solar energy. The soil is the reactor and exchanger of energy and matter and, as such, is the terrestrial environmental integrator and supporter of life on Earth. The environment as expressed in this context is a permeable membrane which shapes life forms, with an inherent capacity and resilience to function and respond to stimulii. Soil is an open and metastable thermodynamic system. It functions because of an external energy supply. The soil is remarkably resilient but its capacity and resilience are limited. Although soil is important for plant production for agriculture and forestry, its role in Nature is more vital in fundamental earth processes and moderating the effects of human manipulation. The soil is finite, scarce and fragile. Human activity may affect the soils' capability to function as an environmental integrator and moderator, if rates of human interference are greater than the rates that sustain soil processes.