Dirt: The Erosion of Civilizations - Kootenay Local Agricultural Society

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inhabitants. Two centuries later, in 1697, the Spanish ceded the western
third of the island to the French, who imported African slaves to work timber
and sugar plantations serving European markets. The colony’s half million
slaves revolted in the late eighteenth century, and in 1804 Haiti
became the world’s first republic of freed citizens to declare independence—from
France, Europe’s first republic.
Subsequent cultivation on steep slopes converted about a third of the
country to bare rocky slopes incapable of supporting agriculture. In colonial
times, there were reports of extensive erosion on upland coffee and
indigo plantations and plantation owners could count on only three years
of productive crops from upland fields. Widespread cultivation of steep
slopes began again in the mid-twentieth century when subsistence farmers
spread back into the uplands. By 1990, 98 percent of Haiti’s native tropical
forest was gone. Common erosion control measures such as piling up
soil into mounds, or piling up soil against stakes placed along contour to
create small terraces, were not very effective in controlling erosion on steep
slopes.
islands in time
Eroded areas
Active rofabards
Glaciers
Figure 26. Map of Iceland showing the extent of areas considerably to severely
eroded, glacial ice, and uneroded soils (created from data provided courtesy of
Einar Grétarsson).
Soil