In general terms, is the ability to maintain balance of a certain process or state in any system. It is now most frequently used in connection with biological and human systems. For humans to live sustainably, the Earth\92s resources must be used at a rate at which they can be replenished.
However, there is now clear scientific evidence that humanity is living unsustainably, and that an unprecedented collective effort is needed to return human use of natural resources to within sustainable limits.
