Dirt: The Erosion of Civilizations - Kootenay Local Agricultural Society

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figuring the downstream end of modern sewage systems to close the loop
on nutrient cycling by returning the waste from livestock and people back
to the soil. As archaic as it may sound, someday our collective well-being
is likely to depend on it.
At the same time, we can’t afford to lose any more farmland. Fifty years
from now every hectare of agricultural land will be crucial. Every farm that
gets paved over today means that the world will support fewer people
down the road. In India, where we would expect farmland to be sacred,
farmers near cities are selling off topsoil to make bricks for the booming
housing market. Developing nations simply cannot afford to sell off their
future this way, just as the developed world cannot pave its way to sustainability.
Agricultural land should be viewed—and treated—as a trust
held by farmers today for farmers tomorrow.
Still, farms should be owned by those who work them—by people who
know their land and who have a stake in improving it. Tenant farming is
not in society’s best interest. Private ownership is essential; absentee landlords
give little thought to safeguarding the future.
Viewed globally, humanity need not face a stark choice between eating
and saving endangered species. Protecting biodiversity does not necessarily
require sacrificing productive agricultural land because soils with high
agricultural productivity tend to support low biodiversity. Conversely,
areas with high biodiversity tend to be areas with low agricultural potential.
In general, species-rich tropical latitudes tend to have nutrient-poor
soils, and the world’s most fertile soils are found in the species-poor loess
belts of the temperate latitudes.
Much of the recent loss of biodiversity has been encouraged by government
subsidies and tax incentives that allowed clearing and plowing of
lands (like tropical rainforests) that can be profitably farmed for only a
short period and are often abandoned once the subsidies lapse (or the soil
erodes). Unfortunately, most developing countries are in the tropical latitudes
where soils are both poor in nutrients and vulnerable to erosion.
Despite this awkward geopolitical asymmetry, it is myopic to ignore the
reality that development built upon mining soil guarantees future food
shortages.
There are three great regions that could sustain intensive mechanized
agriculture—the wide expanses of the world’s loess belts in the American
plains, Europe, and northern China, where thick blankets of easily farmed
silt can sustain intensive farming even once the original soil disappears. In
the thin soils over rock that characterize most of the rest of the planet, the
life span of civilizations