Measuring Multiple Enzyme Activities in One Sample As Soil Health Indicators of Biogeochemical Cycling.

Enzyme activities (EAs) have long been used as an indicator of soil quality/health because of their role in the decomposition of organic materials with global impacts on biogeochemical cycling, soil organic matter dynamics and soil productivity. EAs most commonly assessed are hydrolases such as phosphatases, sulfatases, b-glucosidase or b-glucosaminidase, which hydrolyze various chemical bonds (i.e., ester, glucosyl) in organic matter thereby, releasing plant available inorganic forms of phosphates or sulfates, or monomer carbohydrates used as energy sources by soil organisms. Generally, these hydrolyzing EAs are measured in air-dried soil with appropriate substrates under similar assays in regards to buffers pH, colorimetric indicator and incubation time facilitating comparisons due to management across soils. The burgeoning interest in soil health has created a need for high-throughput assays that can be simpler and more cost effective compared to measuring multiple enzymes independently with multiple steps for each assay. We provide options for developing biogeochemical potential indexes for two (or more) EAs evaluated simultaneously that can reduce the time, resources and wastes generated from the assay of these four enzyme activities individually.