Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/16/2019
Publication Date: 7/16/2019
Citation: Acosta Martinez, V., Perez-Guzman, L., Johnson, J.M. 2019. Simultaneous determination of ß-glucosidase, ß-glucosaminidase, acid phosphomonoesterase, and arylsulfatase in a soil sample for a single biogeochemical index. Meeting Abstract. Presentation. Sacramento, CA, July 16-18, 2019.
Technical Abstract: Four enzymes activities (EAs) have been targeted as soil health indicators for their important role in C (ß-glucosidase), N (ß-glucosaminidase), P (acid phosphomonoesterase) and S (arylsulfatase) cycling. Although these EAs can be measured in air-dried soil following the same approach (detection of released p-nitrophenol after 1hr incubation at 37C), the current protocol is time consuming as each EA is measured independently. Thus, we developed an approach for simultaneous determination of the four EAs in the same soil sample. Soil samples with a wide range in soil organic C (4–44' g' C' /kg' soil) were used to provide an approach that can be used across regions. Our combined assay that will be referred to as “CNPS activity”, showed positive significant (p < 0.001) correlations with the sum of the individual EAs (r = 0.97) and with soil organic C (r = 0.94) and total nitrogen (r = 0.93). This combined assay distinguished among diverse agroecosystems similarly to the sum of the individual EAs for Minnesota soils (corn-soybean = grass < rotation), and for Texas soils (continuous cotton < grass < Conservation Reserve Program). The CNPS activity will reduce time, resources and chemical waste than assaying the EAs individually, while generating a single index of soil organic matter dynamics and biogeochemical cycling potential across regions.