Soil Nutrient Dynamics and Farming Sustainability Under Different Plum Orchard Management Practices in the Pedoclimatical Conditions of Moldavian Plateau

Abstract

Soil health is essential for sustainable agriculture, influencing ecosystem health and orchard productivity of plum orchards. Global challenges such as climate change and soil contamination threaten to affect fertility and food security, requiring sustainable practices. The study assessed the effect of different orchard management practices on soil quality and nutrient distribution in Prunus domestica L. orchard located on the Moldavian Plateau in northeastern Romania under temperate humid subtropical climate conditions. Two systems were analyzed: conventional (herbicide-based) and conservative (cover crop-based). Soil samples (0–20 cm and 20–40 cm) were analyzed for soil organic carbon (SOC), total nitrogen (Nt), available phosphorus (P), and potassium (K). Results showed that conservative management improved soil health by increasing SOC nutrient cycling, mainly through organic matter inputs. Compared to 2022, the effectiveness of phosphorus in the conservative management system significantly increased (by 6%) in 2023, while potassium content decreased (by 30%), suggesting potential nutrient competition or insufficient replenishment under organic practices. SOC levels remained stable, supporting long-term carbon inputs. Conventional management maintained phosphorus and potassium but showed lower SOC levels and higher risks of soil fertility depletion. Strong correlations between SOC and nutrient indicators emphasize the critical role of organic inputs in nutrient mobilization. The findings indicate that cover crops are essential for sustainable soil management by enhancing carbon sequestration and nutrient cycling, thereby supporting the long-term sustainability of agricultural systems.