Abstract

Lignin plus cutin (LIC) content and biological stability index (BSI) are well-recognized indexes of potentially recalcitrant carbon (C) in organic products, and C / nitrogen (N) and lignin/N ratios have been related to potentially mineralizable N (PMN). Our objective was to use Fourier-transform near-infrared (FT-NIR) spectroscopy to estimate PMN and BSI of plant residues, composts, and manures. We also evaluated FT-NIR for determining the C/N, LIC/N, and BSI/N ratios as indexes of N mineralization in selected organic products. We analyzed 148 organic products for biochemical composition and total C and N. A subset of 10 products was incubated in a sandy soil to determine PMN. The FT-NIR successfully determined lignin and cutin ( LIC) and BSI from r(2), the ratio of prediction to standard deviation, and the ratio error range criteria. The PMN was less closely related to the C/N ratio (r(2) = 0.64) than the BSI/N (r(2) = 0.84) and LIC/N (r(2) = 0.87) ratios. There was some N immobilization at an early stage of incubation when C/N, LIC/N, and BSI/N ratios exceeded 14, 10, and 15, respectively. There is a need to characterize a larger number of organic compounds in the soluble and LIC fractions to improve the BSI equation.

Keywords

Biological stability index; C/N ratio; crop residues; lignin/N ratio; N mineralization and immobilization; organic amendments and fertilizers

Published in

Communications in Soil Science and Plant Analysis
2010, Volume: 41, number: 8, pages: 917-934
Publisher: TAYLOR & FRANCIS INC

SLU Authors

• Bolinder, Martin

  • Department of Soil and Environment, Swedish University of Agricultural Sciences
    
  • Laval University

UKÄ Subject classification

Agricultural Science


Publication identifier

DOI: https://doi.org/10.1080/00103621003646014

Permanent link to this page (URI)

https://res.slu.se/id/publ/59730