Environmental cost and steady state: the problem of adiabaticity in the emergy value

Self-organizing activity of ecosystems can be investigated by means of different so-called goal functions. Emergy (Odum, 1988) and exergy (Jّrgensen, 1992) have been proposed to account for embodied quality and organization of systems. The meaning of emergy and exergy as work potential indicators is stressed: they appear to be suitable measures of work potential until the resources is used up, while they seem to be incomplete indicators when the process is considered in the larger perspective of the surrounding environment. If the biosphere viewpoint is considered, i.e. the maintenance of the equilibria developed over millennia of self-organization, adiabatic correction terms have to be taken into account, in order to evaluate the shift of the system far from the sustainable steady state.