Management effects on the dynamics and storage rates of organic matter in long-term crop rotations

Academic Article


  • Factors controlling soil organic matter (SOM) dynamics in soil C sequestration and N fertility were determined from multi-site analysis of long-term, crop rotation experiments in Western Canada. Analyses included bulk density, organic and inorganic C and N, particulate organic C (POM-C) and N (POM -N), and CO2-C evolved during laboratory incubation. The POM-C and POM-N contents varied with soil type. Differences in POM-C contents between treatments at a site (δPOM-C) were related (r2= 0.68) to treatment differences in soil C (δSOC). The CO2-C, evolved during laboratory incubation, was the most sensitive indicator of management effects. The Gray Luvisol (Breton, AB) cultivated plots had a fivefold difference in CO2-C release relative to a twofold difference in soil organic carbon (SOC). Soils from cropped, Black Chernozems (Melfort and Indian Head, SK) and Dark Brown Chernozems (Lethbridge, AB) released 50 to 60% as much CO2-C as grassland soils. Differences in CO2 evolution from the treatment with the lowest SOM on a site and that of other treatments (δCO2-C) in the early stages of the incubation were correlated to δPOM-C and this pool reflects short-term SOC storage. Management for soil fertility, such as N release, may differ from management for C sequestration. Key words: Multi-site analysis, soil management, soil C and N, POM-C and N, CO2 evolution
  • Authors

  • Paul, EA
  • Collins, HP
  • Paustian, K
  • Elliott, ET
  • Frey, Serita
  • Juma, N
  • Janzen, H
  • Campbell, CA
  • Zentner, RP
  • Lafond, GP
  • Moulin, AP
  • Status

    Publication Date

  • February 2004
  • Has Subject Area

    Published In


  • CO2 evolution
  • POM-C and N
  • multi-site analysis
  • soil C and N
  • soil management
  • Digital Object Identifier (doi)

    Start Page

  • 49
  • End Page

  • 61
  • Volume

  • 84
  • Issue

  • 1