Soil health assessment across paired cropland and reference sites under diverse edaphic and climatic conditions

Abstract Soil health is critical to sustain crop productivity and ecosystem functions. However, assessing soil health remains challenging due to variability in soil types, management practices, and climatic conditions. The objective of this study is to compare selected soil health indicators between croplands and undisturbed reference sites across a gradient of soil and climatic conditions in Nebraska. Four paired sites were selected from Cropland Reference Ecological Units representing distinct soil textures and precipitation regimes in Major Land Resource Areas (MLRAs) 106 and 67A. Soil samples were analyzed for organic matter (OM), β‐glucosidase (BG) and phosphomonoesterase (PME), inorganic phosphorus (P), pH, bulk density (BD), and microbial community components (fungal‐to‐bacterial ratio and total fungal biomass). Reference sites with higher precipitation and finer soil textures had greater OM, BG, and PME and lower pH than those with low precipitation and coarse soils. Croplands at sites with manuring and no‐till recorded lower OM depletion from reference site levels (28%) than sites with continued conventional tillage (31%–54%), underscoring the benefits of low‐intensity land preparation and organic amendments. Croplands had lower PME activity than reference sites, suggesting that crop production entirely depends on P input to meet crop P requirements. A manured cropland had a higher BD than the reference site, illustrating the overall impact of management on soil health, which would have been otherwise overlooked had it not been compared against reference sites. Such comparisons between croplands and reference sites with regional consideration also help establish site‐specific soil health targets.