Soil Fertility Transitions in the Context of Industrialization, 1750-2000

Fertile soils are essential for human health and nutrition and formed the foundation of human economies for millennia. Soils deserve close attention from environmental and economic historians and sustainability scientists. Most soil history literature addresses failure: misuse of soil, uncontrolled erosion, and the resulting collapse of past civilizations. More important, however, and of urgent interest for our present and future prosperity, are the mundane ways that historical farm communities sustained soil health, even while cultivating the same land for centuries. This article explains five strategies by which European and North American farmers accessed, recycled, replenished, and sustained soil fertility over 250 years. By evaluating inputs, extractions, transfers, and annual balances of potassium, phosphorus, and, especially, nitrogen, it models historical soil management in a variety of agroecosystems in various geographical settings and through time. This biophysical environmental history, based on socioecological metabolism methods borrowed from sustainability science, reveals ongoing adaptation to shifting social and environmental contexts. As industrialization, global trade, and population accelerated, farmers adjusted their soil fertility strategies to keep up with new pressures and opportunities. Each solution to existing soil fertility constraints created new obstacles and bottlenecks. Through the past quarter millennium, farm sustainability meant constant readjustment to new circumstances. As farmers innovated crop choices and rotations, corralled livestock, adopted new technologies, deployed novel energy sources, and expanded into new lands, they increased food productivity to feed growing world population and supply expanding markets, while maintaining the supply of soil nutrients necessary to fertilize next year's crop.