Impact of Compost Application during 5 Years on Crop Production, Soil Microbial Activity, Carbon Fraction, and Humification Process

ABSTRACTCompost amendment is considered as a practical tool to increase the soil organic matter (SOM), which contributes to agricultural sustainability. The objective of the present work was to evaluate the impacts of organic soil management over 5 years on orchard prune production (Prunus salicina), microbial activity, soil carbon (C) fraction, and stabilization degrees of soil humification. Plot experiment was designed with two different soil managements: i) for minimizing anthropogenic disturbances, only mulching of orchard residues derived from prune tree plot area was applied to soil surface (S + V); and ii) the amendment of composted manure was annually practiced in addition to the utilization of orchard residues inside the plot area (S + V + C). After 5 years, the soil with the continuous compost application (S + V + C) showed higher productivity of Prunus salicina (21.4%), greater fruit diameter (7.8%), and heavier fruit weight (22.4%) than the soil without compost application (S + V). Nutrient co...