NATURAL RESOURCES

Any portion of the natural environment, such as air, water, soil, botanical and zoological resources, and minerals. Renewable resources can potentially last indefinitely (provided stocks are not over-exploited) without reducing the available supply because it is replaced through natural processes (either because it recycles quite rapidly, such as water, or because it is alive and can propagate itself or be propagated, such as organisms and ecosystems). Non-renewable resources (such as coal and oil) may eventually be replaced by natural processes, but these occur over long periods of geologic time rather than within the time frame of current civilisation, and their consumption necessarily involve their depletion. Scialabba (1998)