Yes, we are in the post-industrial age, and the
production of autos, houses, airliners and other “goods’ can be
taken for granted. But Sandra Postel in Pillar of Sand warns that
there is no such thing as a “post-agricultural age.” Because
irrigated agriculture provides 40 percent of the globe’s food
today, and because in the past, civilizations based on irrigation
have often failed, we had better pay
attention.
The problem is, we don’t know what
exactly destroyed ancient Mesopotamia or the civilization built by
the Hohokam in the American Southwest. So we are left to ponder our
present imponderables: climate change, the salting of the earth’s
soils, the silting of reservoirs, the calcifying of massive
bureaucracies such as the U.S. Bureau of Reclamation. We can put a
ruler to any one of these, but how do they interact, with what
speed do they advance, and can our society, which many think is too
ingenious for its own good, figure ways around
them?
Conventionally, which means Malthusian
reasoning, food production is in a race against population
production. At the moment, it is a race run at a slowing rate. In
the 1990s, grain production dropped from the 2 percent annual
growth rate of 1950 to 1990, to this decade’s 1 percent growth
rate. But population growth has also slowed, from 2.2 percent in
1962 to 1.4 percent in 1998. Is the glass half full and filling? Or
half empty and getting emptier?
On balance,
Sandra Postel’s glass is half full. She understands the
salinization and other dangers that could wipe out millions of
hectares of now productive irrigated land. And she knows that even
a 1.4 percent population growth rate adds 80 million people a year
to the earth.
But she traveled widely in writing
this book, and she found many innovations that could buy us time.
Most surprising, perhaps, she became a fan of marketing –
especially the marketing of cheap, efficient, foot-powered
irrigation pumps that allow people with small plots of land in
Third World countries to reach groundwater lying only a few feet
beneath the surface. This water, when spread over the land, gives
them the food and cash not just to survive, but also to create the
base of a vital economy.
Overall, this book is
that rarest of works: a calm approach to the intertwined questions
of population and food. Instead of going into the research with all
the answers, the writer went in with good questions and found
interesting answers. As a bonus, it’s filled with engaging
anecdotes (case studies, if you prefer), and is a well-written,
quick read.
* Ed Marston
This article appeared in the print edition of the magazine with the headline Pillar of Sand.
Republish our articles for free, online or in print, under a Creative Commons license.
