Summary
Published in Ecosphere 6(5): 1-22. https://doi.org/110.1890/ES14-00209
Long-term forest soil monitoring and research often require a comparison of laboratory data generated at different times and in different laboratories. Quantifying the uncertainty associated with these analyses is necessary to assess temporal changes in soil properties. Forest soil chemical properties, and methods to measure these properties, often differ from agronomic and horticultural soils. Soil proficiency programs do not generally include forest soil samples that are highly acidic, high in extractable Al, low in extractable Ca and often high in carbon. To determine the uncertainty associated with specific analytical methods for forest soils, we collected and distributed samples from two soil horizons (Oa and Bs) to 15 laboratories in the eastern United States and Canada. Soil properties measured included total organic carbon and nitrogen, pH and exchangeable cations. Overall, results were consistent despite some differences in methodology. We calculated the median absolute deviation (MAD) for each measurement and considered the acceptable range to be the median 6 2.5 3 MAD. Variability among laboratories was usually as low as the typical variability within a laboratory. A few areas of concern include a lack of consistency in the measurement and expression of results on a dry weight basis, relatively high variability in the C/N ratio in the Bs horizon, challenges associated with determining exchangeable cations at concentrations near the lower reporting range of some laboratories and the operationally defined nature of aluminum extractability. Recommendations include a continuation of reference forest soil exchange programs to quantify the uncertainty associated with these analyses in conjunction with ongoing efforts to review and standardize laboratory methods.
Sector(s):
Forests
Categorie(s):
Scientific Article
Theme(s):
Forest Ecology, Forestry Research, Forests
Departmental author(s):
Author(s)
ROSS, D.S., S.W. BAILEY, R.D. BRIGGS, J. CURRY, I.J. FERNANDEZ, G. FREDRIKSEN, C.L. GOODALE, P.W. HAZLETT, P.R. HEINE, C.E. JOHNSON, J.T. LARSON, G.B. LAWRENCE, R.K. KOLKA, Rock OUIMET, D. PARÉ, D. deB. RICHTER, C.D. SCHIRMER and R.A. WARBY
Year of publication :
2015
Format :
PDF available upon request
How to get the publication :
Keywords :
sols forestiers, variabilité interlaboratoire, méthodes de laboratoire, analyse du sol, écosystèmes et environnement, article scientifique de recherche forestière, forest soils, inter-laboratory variability, laboratory methods, soil analysis, ecosystems and environment
