Dirt: The Erosion of Civilizations - Kootenay Local Agricultural Society

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Life Span of Civilizations
Speak to the earth, and it shall teach thee.
job 12:8
after two hundred years, the contrasting visions of Malthusian
pessimism and Godwinian optimism still frame debate over whether technological
innovation will keep meeting society’s growing agricultural needs.
Preventing a substantial decline in food production once we exhaust fossil
fuels will require radically restructuring agriculture to sustain soil fertility,
or developing massive new sources of cheap energy if we continue to rely
on chemical fertilizers. But the future is clear if we continue to erode the
soil itself.
Estimating how many people Earth can support involves assumptions
about trade-offs between population size, quality of life, and environmental
qualities such as biodiversity. Most demographic estimates anticipate
more than ten billion people on the planet by the end of this century.
Whether we endorse the National Conference of Catholic Bishops’ apparent
belief that the world could comfortably support forty billion people,
or Ted Turner’s view that four hundred million would be plenty, feeding
even the middle range of such estimates presents an impossible challenge.
For even if we were we to somehow harness Earth’s full photosynthetic production
with the same efficiency as the 40 percent now devoted to supporting
humanity, we could support fifteen billion people—and share the
planet with nothing else.
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