Thinking Through Soil: Wastewater Agriculture in the Mezquital Valley

To think through soil is to engage with some of the most critical issues of our time. In addition to its agricultural role in feeding eight billion people, soil has become the primary agent of carbon storage in global climate models, and it is crucial for biodiversity, flood control, and freshwater resources. Perhaps no other material is asked to do so much for the human environment, and yet our basic conceptual model of what soil is and how it works remains surprisingly vague.

In cities, so...