Dirt: The Erosion of Civilizations - Kootenay Local Agricultural Society

eight
Dirty Business
A nation that destroys its soils, destroys itself.
franklin d. roosevelt
several years after seeing the rapid pace of soil destruction in the
lower Amazon I found the antithesis while leading an expedition in eastern
Tibet. Driving the region’s rough dirt roads I saw a thousand-year-old agricultural
system along the valley of the Tsangpo River. We were there to study
an ancient ice-dammed lake that drained in a cataclysmic flood down the
Himalayan gorge through which the river slices to join the Ganges. Looking
for outcrops of ancient lakebeds we drove through villages full of chickens,
yaks, and pigs. All around the towns, low silt walls trapped soil in fields
of barley, peas, and yellow flowers with seeds rich in canola oil.
After a few days it became obvious that corralling dirt was only part of
the secret behind ten centuries of farming the lakebed. Following an unsupervised
daily rhythm, Tibetan livestock head out to the fields during the
day, fend for themselves, and come home at night. Driving back through
towns at the end of each day’s fieldwork, we saw pigs and cattle waiting
patiently to reenter family compounds. These self-propelled manure dispensers
were prolific; even a brief rain turned fields and roads to flowing
brown muck.
The night after finding the remains of the glacial dam that once impounded
the lake, we stayed at a cheap hotel in the end-of-the-road town
of Pai. Homemade sleeping platforms served as beds in sleeping stalls
barely separated by unfinished plank walls. The proprietor advised us on
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