|NUNES, MARCIO - Orise Fellow
|DICK, RICHARD - The Ohio State University
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 9/16/2020
Publication Date: 8/15/2021
Citation: Acosta Martinez, V., Perez-Guzman, L., Veum, K.S., Nunes, M.R., Dick, R. 2021. Metabolic Activity - Enzymes. In: Karlen, D.L., Stott, D.E., Mikha, M.M. Soil Health Series. Volume 2 Laboratory Methods for Soil Health Analysis. Hoboken, NJ: John Wiley & Sons. 194-250. https://doi.org/10.1002/9780891189831.
Interpretive Summary: Enzymes are important in decomposing plant, animal, and microbial materials that keep the soil functioning and healthy. This is why ARS scientists from Lubbock TX, Ames IA, and Columbia MO together with a professor from The Ohio State University wrote a chapter on four specific enzyme activities important in the recycling of carbon, carbon and nitrogen, phosphorus, and sulfur in soils. The chapter provide a simple method to measure the enzyme activities and distinguish changes in soil health due to management practices within one to three years of their implementation. Their chapter will facilitate adoption of the analysis of enzyme activities by commercial and agency labs that serve producers, and to improve interpretation of enzyme activity data to select management practices that improve the health of our soils.
Technical Abstract: Enzymes drive the decomposition of plant, animal, and microbial debris, regulating essential functions that shape a healthy soil. Soils vary in their amount, types, and distribution of enzymes due to differences in soil texture, organic matter content, chemistry, and the biota that produce them. However, management practices and climatic conditions will also alter enzyme stability, fate, and overall activity. Among other microbial measurements, EAs are sensitive indicators of soil health as they can distinguish among management practices within one to three years of their implementation. The simple and high throughput methodology available to measure enzyme activities (EAs) makes them practical for commercial adoption to help producers evaluate how their management selections influence their soil’s health. Establishing soil health indices will depend on linking EAs to the delivery of essential functions for agroecosystem sustainability within diverse soil types, management practices, and climatic regions. This chapter will focus on ß-glucosidase, ß-glucosaminidase, acid or alkaline phosphomonoesterase (hereafter phosphatase), and arylsulfatase as biochemical indicators of soil health for C, C and N, and P and S cycling, respectively. The original method for these EAs will be presented along with modifications that reduce time and cost to enable adoption by commercial and agency service labs. Approaches to improve the application and interpretation of these four EAs for evaluation of soil health across soil types and management practices will be provided. Finally, this chapter will highlight our vision for future research using these enzymes as soil health indicators and ultimately including them in national and international soil health assessments.