Biological And Technical
Can a material safely re-enter the natural world?
The first thing that most people notice about the diagram is the separation into two distinct halves, or cycles, which represent two fundamentally distinct flows of material: biological and technical.
Biological materials – represented in green cycles on the left side of the diagram – are those materials that can safely re-enter the natural world, once they have gone through one or more use cycles, where they will biodegrade over time, returning the embedded nutrients to the environment.
Technical materials – represented in blue on the right hand side – cannot re-enter the environment. These materials, such as metals, plastics, and synthetic chemicals, must continuously cycle through the system so that their value can be captured and recaptured.