As I did some reading in preparation of writing this blog, I found there are various definitions of soil health. And I am sure for as many definitions as there are, we each have our own ideas as to what defines soil health. The USDA-NRCS Soil Health web page defines soil health as "the continued capacity of soil to function as a vital living ecosystem that sustains plants, animals, and humans." If I had to define soil health I would say it is a combination of soil physical, biological and chemical functions. Perhaps an agronomic analogy is the disease triangle. We know that in order to have disease present we must have the host, the pathogen and the right environmental conditions. To define soil health we must be able to measure and evaluate the physical, biological, and chemical aspects of the soil in the context of space, time and use of the soil.
Dr. Mahdi Al-Kaisi wrote this article which provides a good place to start our understanding, What is soil health and how can we improve it? For additional learning and understanding you can access the presentations given at the Soil Health Conference held in Ames in February at Speaker Presentations.