『Abstract
The neoclassical model of production assumes that capital and
labor are primary inputs to production. Consistent with this assumption,
the neoclassical model of natural resource scarcity assumes that
real resource prices or capital-labor extraction costs are the
appropriate empirical indicators of scarcity. In their seminal
work, Barnett and Morse found that capital-labor costs per unit
of extractive output declined throughout most of this century,
a trend they attributed to “self-generating” technological change.
A biophysical model of the economic process assumes that capital
and labor are intermediate inputs produced ultimately from the
only primary factor of production: low entropy energy and matter.
A biophysical model of scarcity posits that direct and indirect
energy costs of resource extraction increase with depletion because
lower quality deposits require more energy to locate, upgrade,
and otherwise transform into useful raw materials. I repeated
Barnett and Morse's analysis from a biophysical perspective using
energy costs to measure changes in the quality of extractive output
in U.S. agriculture, forestry, fishing, and mining industries.
In most cases, energy costs per unit of output increases with
depletion. Results show that labor and capital costs declined
because large quantities of surplus fossil fuel substituted for
and increased the productivity of labor and capital. Substantial
increases in energy costs were found in agriculture, fisheries
and the mining of metals and fossil fuels. Energy costs per unit
output in forest products declined. I discuss possible trends
for future costs in light of the result that the energy cost of
fossil fuels is also rising.』
Introduction
The neoclassical model of natural resource scarcity
A Biophysical critique of the neoclassical model
Primary factors versus intermediate inputs
The importance of energy surplus
Resource scarcity from a biophysical perspective
Empirical measures of scarcity from a biophysical perspective
Measuring output and energy costs
The energy cost of extractive output
Mining
Agriculture
Forestry
Fisheries
Discussion of results
Mining
Agriculture
Forest products
Fisheries
Comparison with economic measures of scarcity
Conclusions
References