The Development and Evolution of the Soil Health Nutrient Tool (aka Haney Test) after Ten Years of Implementation in a Commercial Agricultural Laboratory

Authors

Lance Michael Gunderson, University of Nebraska-LincolnFollow

First Advisor

Rhae Drijber

Degree Name

Doctor of Philosophy (Ph.D.)

Department

Agronomy and Horticulture

Date of this Version

11-2023

Document Type

Dissertation

Citation

A dissertation presented to the faculty of the Graduate College at the University of Nebraska in partial fulfillment of requirements for the degree of Doctor of Philosophy

Major: Agronomy and Horticulture

Under the supervision of Professor Rhae Drijber

Lincoln, Nebraska, 2023

Comments

Copyright 2023, Lance Michael Gunderson. Used by permission

Abstract

The growing focus on soil health and regenerative agriculture has brought about the need for new integrated approaches for the analysis of soil. Prior, commercial agricultural laboratories relied on methods to measure chemical properties of the soil, such as pH and nutrients. The Soil Health Nutrient Tool (aka Haney Test) developed by Dr. Rick Haney (United States Department of Agriculture, Agricultural Research Service (USDA-ARS), Blackland Research and Extension Station, Temple, Texas) integrates chemical and biological properties to provide a more holistic understanding of soil fertility management. Following adoption by commercial laboratories in 2013, criticisms regarding variability in measurements and lack of calibration were apparent. In this research, we present the development of new tools and instrumentation to reduce variability of specific measures, namely soil respiration, used as part of the test. The development of the Soil Respiration-1 (SR-1) instrument, which employs an infrared gas analysis (IRGA) detector for measuring carbon dioxide (CO₂) was compared to the Solvita® gel system. The data suggest that Solvita® underestimates CO₂ respiration at values above 100 mg CO₂-C kg^-1 and overestimates values below 30 mg CO₂-C kg^-1, compared to the SR-1, leading to compounding effects on the overall results of the Haney Test. These findings led to the development of the Mini-Cube using nondispersive infrared (NDIR) microsensor technology as a potential cost-effective solution compared to the SR-1. The comparison yielded a strong correlation (r² = 0.99, p < 0.001) and suggests that the Mini-Cube could be a viable, cost-effective option for soil respiration in commercial laboratories. We then explored complimentary measures to CO₂respiration by coupling an IRGA CO₂ sensor with UV Flux to measure oxygen (O₂) consumption. The results show that O₂ uptake is correlated (r² = 0.97, p < 0.001) to CO₂ efflux, and could be used in lieu of CO₂ measurements for biological activity. Finally, we explore the utility of the Haney test as a tool for regenerative agriculture verification processes using Regen Certified® and Microbially Verified Carbon scoring.

Advisor: Rhae A. Drijber

Recommended Citation

Gunderson, Lance Michael, "The Development and Evolution of the Soil Health Nutrient Tool (aka Haney Test) after Ten Years of Implementation in a Commercial Agricultural Laboratory" (2023). Dissertations and Doctoral Documents from University of Nebraska-Lincoln, 2023–. 55.
https://digitalcommons.unl.edu/dissunl/55