People want to find out how serious problems are and how they're changing through time. The science behind the NRI, Thompson said, comes from Iowa State's Statistical Laboratory, based in the statistics department. Established in 1933, it was the first statistical center of its type in the nation, bringing together people trained in statistical theory and application to work on real world problems. The NRI is seemingly a whole-Earth catalog of the United States. Data collected include information on soil characteristics, land use, soil erosion, vegetative cover and ecological variables such as habitat diversity.
Collectors note bodies of water, buildings and roads.
They chart land reverting to wetlands and land that is being farmed. Information can be as specific as changes in crops planted on a farm and the effects those crops have on the health of that soil, Thompson said. Photo by Bob Elbert.