With the goal of helping to improve conservation planning, the U.S. Department of Agriculture assembled a preliminary set of standard indicators and associated laboratory procedures to assess soil health. These measures, recommended through a multi-organizational collaboration among soil health experts in the federal, university, public and private sectors, were posted to the Federal Register for public review and comment through December 13, 2018.
"Standardized measures give us consistency in scientifically assessing soil health and will improve our ability to evaluate soils across the United States using methods that are objective and actionable," said Bill Northey, USDA's Under Secretary for Farm Production and Conservation.
The USDA's Natural Resources Conservation Service and the Agricultural Research Service led a team of technical experts in selecting methods to assess six standard soil health indicators, which focus on key physical and biological processes that must function well in healthy soils. Those indicators are:
• organic matter recycling and carbon sequestration,
• soil structure stability,
• general microbial activity,
• carbon food source,
• bioavailable nitrogen, and
• microbial community diversity.
The federal agency states that "laboratory methods for assessing each indicator were chosen based on interpretability, ease of use, cost effectiveness, measurement repeatability, and ability to inform agricultural management decisions," and that the assessment measures were developed to improve their service to the public and facilitate data sharing, "leading to broader collaboration among soil health experts," nationwide.
The recommended standards can be found here. (https://www.federalregister.gov/documents/2018/09/14/2018-19985/notice-of-recommended-standard-methods-for-use-as-soil-health-indicator-measurements)