Decomposition Rate of Organic Residues and Soil Organisms’ Abundance in a Subtropical <i>Pyrus pyrifolia</i> Field

Abstract

The use of mulching, compost, and their interaction on organic residue (OR) decomposition rate (k), time of residue decay, primming effect, and soil organisms’ community composition was tested in a 16-year P. pyrifolia field experiment conducted from January 2020 to June 2021. A 2 × 2 factorial design was used with compost and mulching as the two factors within four blocks. OR decomposition was characterized by using litter bags with different mesh, and soil organisms were identified at family level. The half-decay rate (hd), total-decay rate (td), and remaining residue mass (Rm) varied among the organic residue management and mesh-type. The highest values of k and primming effect were found in litter bags with 15 mm2 size containing compost in the plots that received compost. For soil organisms’ abundance and richness, the highest values were found on plot that received both mulching and compost. The observed results suggested that the OR management determined organic matter decomposition, soil organisms’ abundance and richness in an Acrisols of the Southern Brazil. Soil organisms were the main factors contributing to the data variance (e.g., Acaridae, Blattidae, Chrysopidae, Halictophagidae, and Forficulidae).

Keywords

• compost
• litterbags
• mulching
• nutrient cycling
• priming effect
• soil organisms