Agroforestry Systems

, Volume 81, Issue 3, pp 203–211

Carbon, nitrogen and organic C fractions in topsoil affected by conversion from silvopastoral to different land use systems

  • Eduardo S. Matos
  • Dirk Freese
  • Eduardo S. Mendonça
  • Anna Slazak
  • Reinhard F. Hüttl
Article

DOI: 10.1007/s10457-010-9314-y

Cite this article as:
Matos, E.S., Freese, D., Mendonça, E.S. et al. Agroforest Syst (2011) 81: 203. doi:10.1007/s10457-010-9314-y

Abstract

The conversion of silvopasture to different land use systems cause effective changes in soil carbon distribution, due to disturbances in soil aggregation promoted by soil management and changes in crop residues inputs and decomposability. We evaluate the C and N stocks, and organic C fractions in soils under continuous arable land (AR) and silvopasture with apple trees and grass (SP); and after 4 years of conversion from silvopasture to arable land (SP-AR) and grassland (SP-GL). Total N (TN) and organic C (TOC), as well as microbial biomass carbon (CMB), light fraction (CLF) and heavy fraction (CHF) were evaluated at two different depths (0–10 and 10–20 cm). After 4 years of conversion, SP-AR and SP-GL presented C and N stocks similar to the observed for SP when the 0–20 cm depth was considered. However, AR presented TOC and TN stocks around 21 and 10% lower than SP, respectively. SP-AR tended to present the lowest CMB stocks and was positively correlated with salt extractable organic C (r2 = 0.60, P < 0.001). CLF values declined by 62% from 0–10 to the 10–20 cm at SP and SP-GL, however there was no variation with increasing depth for AR and SP-AR. CHF represented the highest C fraction in soil, corresponding to 82% of TOC. Except for AR, δ13C values of the light fraction increased with increasing depth. In general, heavy fraction tended to be more enriched in δ13C than light fraction. In a long-term, conventional tillage can significantly contribute to reduce TOC and TN stocks when compared to the silvopastoral system.

Keywords

Soil organic matterC poolsFree light fractionδ13C natural abundanceSilvopastureConventional tillage

Copyright information

© Springer Science+Business Media B.V. 2010

Authors and Affiliations

  • Eduardo S. Matos
    • 1
  • Dirk Freese
    • 1
  • Eduardo S. Mendonça
    • 2
  • Anna Slazak
    • 1
  • Reinhard F. Hüttl
    • 1
    • 3
  1. 1.Chair of Soil Protection and RecultivationBrandenburg University of Technology CottbusCottbusGermany
  2. 2.Agricultural Science Center, Department of Plant ProductionFederal University of Espírito SantoAlegreBrazil
  3. 3.GFZ German Research Centre for GeosciencesHelmholtz-Centre PotsdamTelegrafenbergGermany