Comparing the Soil Health Assessment Approaches for the Cropping Systems of Tennessee.

Soil health assessment become crucial when focus shifts to sustainable production. Thus, it is essential to quantify impacts of agricultural management on soil health. This study aims to evaluate the feasibility of using Cornell Assessment of Soil Health (CASH) and Alabama Soil Health Index (ASHI) for quantifying the soil health of Tennessee cropping systems. Since both CASH and ASHI were originally developed for different regions, we hypothesized that they are not sensitive to detect the soil health changes from management differences in agricultural belt of Tennessee. Different soil parameters pertinent to CASH and ASHI were measured using soils from three long-term field experiments, and each parameter was given soil health score based on corresponding scoring approaches. Our feasibility criteria depend on the sensitivity of soil health parameters to differentiate the long-term management changes. For this presentation, we included results from a long-term tillage experiment on a continuous soybean (Glycine max L.) system with six tillage treatments including chisel-plow (CP), disc-plow (DP), moldboard-plow (MP), no-tillage (NT), no-tillage with wheat (Triticum aestivum L.) cover crop (NTW) and no-tillage with wheat-soybean double-cropping (NTWD). Results indicated that soil parameters such as permanganate-oxidizable carbon (POXC), potential mineralized nitrogen (PMN) and 24-hr cumulative CO₂-C (measured by Solvita^®) did not differ significantly among CP, DP, MP and NT treatments but differentiated MP treatment from NTW and NTWD. However, ASHI scores for PMN (10) and CO₂-C (10) fell in very-high category and were not significantly different among treatments. The CASH scores for POXC, for CP, DP, MP and NT treatments were low (<18) and that for NTW and NTWD were medium (33 and 44, respectively). Since CASH and ASHI scores did not show strong differentiation among long-term tillage treatments, the feasibility of these approaches to detect management-induced soil health changes in the cropping systems of Tennessee is questionable.