Decomposition of wheat straw and rye residues as affected by particle size

• Published in: Plant and soil Vol. 189; no. 2; pp. 197 - 203
• Main Authors: Angers, D.A. (Agriculture et Agroalimentaire Canada, Sainte-Foy, Que. (Canada). Centre de Recherches sur les Sols et les Grandes Cultures), Recous, S
• Format: Journal Article
• Language: English
• Published: Dordrecht Kluwer Academic Publishers 01.02.1997; Springer; Springer Nature B.V; Springer Verlag
• Subjects: Agrology; Agronomy. Soil science and plant productions; Atoms & subatomic particles; Biological and medical sciences; Chemical, physicochemical, biochemical and biological properties; CROP RESIDUES; Decomposition; DEGRADACION; DEGRADATION; Fundamental and applied biological sciences. Psychology; Grassland soils; GROSSEUR DES PARTICULES; Life Sciences; MINERALISATION; MINERALIZACION; MINERALIZATION; Organic matter; Organic soils; PAILLE DE BLE; PAJA DE TRIGO; PARTICLE SIZE; Particle size classes; Physics, chemistry, biochemistry and biology of agricultural and forest soils; RESIDU DE RECOLTE; RESIDUOS DE COSECHAS; Rye; SECALE CEREALE; Soil biochemistry; Soil organic matter; Soil science; Straw; TAMANO DE LA PARTICULA; TRITICUM AESTIVUM; Vegetal Biology; Wheat soils; WHEAT STRAW; Monocotyledones; Particle size; Secale cereale; Cultivated soil; Alfisols; Decomposition; Cereal crop; Vegetal waste; Straw; Carbon nitrogen ratio; Gramineae; Organic matter cycle; Mineralization; Angiospermae; Spermatophyta; Agricultural waste; Triticum aestivum; SEIGLE
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1023/a:1004207219678

Effects of contact between the soil and crop residues on the processes of residue decomposition are still poorly understood. The objective of this study was to investigate the effects of residue particle size on the decomposition of wheat (Triticum aestivum L.) straw (C/N= 270) and green rye (Secale cereale) residues (C/N= 9). Residue particle size was used as a means to vary the contact between crop residues and the soil. Carbon mineralization was measured during 102 d for straw and 65 d for rye, on residues ranging in sizes from laboratory model (0.03 cm) to field-scale (10 cm). The soil was a silt (Typic Hapludalf) and the incubation was performed at 15 °C. The effects of particle size on C mineralization varied for the two residues. In the first two days of incubation, decomposition rate of rye increased with decreasing particle size but thereafter, the trend was reversed. In 65 days, 8% more C was decomposed in the 7-cm residues than in the 0.03-cm ones. For wheat straw, early decomposition (3-17 days) was faster for the small-sized particles (0.06 and 0.1 cm). Thereafter, the largest size classes (5 and 10 cm) decomposed faster. After 102 days, the very fine particles (< 0.1 cm) showed the greatest and the intermediate size classes (0.5 and 1 cm), the lowest amount of C mineralized. We hypothesized that greater availability and accessibility of N was responsible for the higher rates of decomposition observed for finely-ground wheat straw while a physical protection of finely ground residues was probably involved in the observed reverse effect for rye.