A New Active C Test to Evaluate Agricultural Soil Health Globally.

Active C is a consistent, sensitive and early indicator of soil health. However, the earlier version of the active C test based on mild oxidation of neutral KMnO4 does not work consistently and sensitivity on mine reclaimed soil, muck soil, Ca-rich soil, Fe- and Al-rich red soils, and submerged or rice soils. The objective of study was to develop, revise and validate the new active C test to be used on soils globally. Soils widely varied in type and origin of formation under different management practices were collected (within and different countries of the world), processed and analyzed with several modifications and additions to standardize the new active C test. Results showed that the new test can consistently and sensitivity account for variations in active C content under variable management practices in different soils.