The term is "productivity". In terms of natural systems it has a
specific meaning in the ecological sense and in the economic
sense as well. Ecologically, productivity is the rate at which
radiant energy is stored by photosynthetic and chemosynthetic of
producer organisms. It is the rate of accumulation of biomass (i.e.
production). Management applied to natural systems is said to be
good or bad based on productivity of management systems or their
components. Productivity in this sense has to do with the
efficiency of use of inputs to produce outputs. One can increase
productivity in this sense by increasing outputs without
increasing inputs or by maintaining outputs while decreasing
Because sustainable agriculture relates to both the physical and
the economic system we should be clear when we are referring to
terms such as productivity. Especially when we may be referring
to the harvested production and not necessarily the rate of
accumulation of production.
Application of nitrogen inputs may increase production and
economic productivity; however, by use of alternative sources of
nitrogen and other management inputs, productivity may or may
not be improved.