The thin layer of topsoil that covers much of the earth’s land surface is the foundation of civilization. As long as soil erosion on cropland does not exceed new soil formation, all is well. But once it does, it leads to falling soil fertility and eventually to land abandonment. As countries lose their topsoil through overgrazing, overplowing, or deforestation, they eventually lose the capacity to feed themselves. Among those facing this problem are Lesotho, Haiti, Mongolia, and North Korea.
Lesotho, one of Africa’s smallest countries with only 2 million people, is paying a heavy price for its soil losses. A U.N. team visiting in 2002 found that crop production there “is declining and could cease altogether over large tracts of country if steps are not taken to reverse soil erosion, degradation, and the decline in soil fertility.” During the last 10 years, Lesotho’s grain harvest dropped by half as its soil fertility fell. Its collapsing agriculture has left the country heavily dependent on food imports.
