You can't buy a better agriculture.

• Author: Cox, Stan
• Position: Biodevastation

The foundation of humanity's food supply is crumbling. The United Nations now estimates that more than 20% of the Earth's cultivated soils have been significantly degraded, while in the United States, 28% of cropland is eroding at an unsustainable rate. Research shows that of all human activities, agriculture is the biggest threat to biodiversity and ecosystems.

Solving agriculture's many problems is not impossible, but the issues involved are complex and the necessary transformations radical. To discuss them is to risk frightening or confusing people. On the other hand, everyone likes good food. So campaigns for more ecologically sound farming practices, especially in the wealthier nations, too often seem to suggest to consumers that with enough effort, we can simply eat our way to a sustainable future.

For example, Organic Valley, America's largest organic-farming cooperative, suggests that "personal food choices affect the health of our bodies and our planet, and drive their future." Likewise, the British Soil Association says that "the buying decisions we make every day are a simple but powerful form of direct action," and Naturalnews.com stresses that "by changing what you buy, you change what farmers will grow and how they will grow it."

But to trust that our personal food-shopping decisions or gardening prowess can push the global food system toward sustainability--to vote three times a day with our forks, as writer Michael Pollan has urged--is to assume that the global agricultural economy operates by the same neighborly rules that prevail down at the local farmers' market.

It doesn't. Eating well-produced food will improve your own health, but not necessarily the health of the Earth's soils. On the one and a half billion hectares of cropland around the globe where our staple foods are grown, the profits of agribusiness and the corporate food industry always get fed first.

Those profits depend primarily on a flood of cheap grain, produce, meat, and milk made possible by the exploitation of soil and human labor. And in the past few decades, a variety of industries--heavy equipment, chemicals, food processing, packaging, transport, advertising, restaurant chains, and others--have grown as appendages on agriculture. In the United States, the dollar outputs of those food-related industries are expanding at two to four times the rate of farming's output. That is creating even more powerful constituencies for policies and practices that...