Getting the basics right on soil enzyme activities: A comment on Sainju et al. (2022)

Soil enzyme activities have been measured since the mid-20th century to help understand how agricultural management practices impact nutrient cycling, and are now considered biological indicators of soil health. However, misconceptions persist about what soil enzyme activities represent and how activities can or cannot be interpreted. The publication by Sainju et al. in Agrosystems, Geosciences & Environment that seeks to evaluate how soil enzyme activities relate to crop yields exemplifies many of these issues. We therefore provide a constructive diagnosis and critique of five common misunderstandings and even errors exemplified by this work. Our ultimate goal in this critique is to catalyze a better understanding of soil enzyme activities and identify where research is needed to close knowledge gaps.