Advancing soil health assessment and improvement strategies in green plum (Vatica mangachapoi Blanco) Orchards: Insights from southeast China

Soil health assessment effectively identifies key soil-limiting factors, enabling targeted decisions for agricultural management. Hence, the selection of representative soil indicators and appropriate assessment approaches is critical for effective evaluation. However, most studies focus solely on evaluating soil health without offering actionable strategies to improve soil health, especially in cash crop systems. In this study, soil samples were collected from green plum orchards in Zhao County, southeast China, to establish a minimum data set (MDS) and assess soil health using the Comprehensive Assessment of Soil Health (CASH), as well as linear (L) and nonlinear (NL) methods. Subsequently, field experiments, including conventional farming practice (CFP) and soil health management (SHM) treatments, were conducted to improve soil health. The results showed that sand, aggregate stability (AgStab), pH, available potassium (AK), iron (Fe), POXC, respiration, and β-glucosidase (BG) were critical indicators for MDS. Soil health indices (SHIs) calculated using the CASH, L, and NL methods based on MDS were 0.48, 0.47, and 0.46, respectively, indicating a moderate level of soil health. SHIs derived from TDS (total data set) and MDS showed a significant positive correlation. The CASH approach was identified as the most effective method for calculating SHI, as it exhibited the highest coefficient of variation (CV) compared to the L and NL methods. In the field experiments, the soil pH, AK, Ca, Mg, SOM, POXC, and protein content were significantly higher under the SHM treatment than under the CFP treatment. The SHM treatment also significantly improved the SHI (0.57) and the yield of green plum (27.3 t ha⁻¹), compared to the CFP treatment (SHI, 0.52; CFP, 13.6 t ha⁻¹). These findings demonstrate that MDS-based PCA is an effective tool for assessing soil health in green plum orchards in Southeast China. Moreover, SHM practices can synergistically improve soil health and crop yield, providing insights into mitigating soil constraints and promoting sustainable development in green plum production systems.