Estimating nitrate, dissolved organic carbon and DOC fractions in forest floor leachates using ultraviolet absorbance spectra and multivariate analysis
| Autor: | Rolf Danielsson, Francis Andreux, Magnus Simonsson, Klaus Kaiser, Jacques Ranger |
|---|---|
| Přispěvatelé: | Microbiologie, Institut National de la Recherche Agronomique (INRA)-Université de Bourgogne (UB), Institute of Soil Science and Plant Nutrition, Martin-Luther-Universität Halle Wittenberg (MLU), Uppsala University, Unité de recherche Biogéochimie des Ecosystèmes Forestiers (BEF), Institut National de la Recherche Agronomique (INRA) |
| Jazyk: | angličtina |
| Rok vydání: | 2005 |
| Předmět: |
Forest floor
[SDV.EE]Life Sciences [q-bio]/Ecology environment Chromatography Chemistry Soil Science Ultraviolet absorbance spectroscopy Molar absorptivity Nitrate Forest floor leachate Absorbance chemistry.chemical_compound Dissolved organic carbon (DOC) Lysimeter Environmental chemistry Soil water Dissolved organic carbon Partial least squares regression XAD-8 fractionation Partial least square (PLS) regression |
| Zdroj: | Geoderma Geoderma, Elsevier, 2005, 124 (1-2), pp.157-168. ⟨10.1016/j.geoderma.2004.04.010⟩ |
| ISSN: | 0016-7061 1872-6259 |
| DOI: | 10.1016/j.geoderma.2004.04.010⟩ |
| Popis: | Multivariate regressions on ultraviolet (UV) absorbance (210–300 nm) data were tested as a potential tool to estimate concentrations of total dissolved organic carbon (DOC), DOC in the XAD-8-adsorbable (hydrophobic) fraction (HoDOC), and dissolved nitrate (NO 3 -N) in forest floor leachates. Partial least square (PLS) regressions were established for 20 zero-tension lysimeter solutions sampled in plots of coniferous and deciduous forest stands from May 2002 to January 2003. These regressions were validated against data from 24 other zero-tension solutions sampled in the same stands. The root mean square error of prediction (RMSEP) was 2.0 mg/l for DOC and 1.6 mg/l for HoDOC. These errors were 39% (DOC) and 20% (HoDOC) smaller than the errors obtained with regressions using only absorbance at 280 nm. For NO 3 -N, RMSEP was 0.12 mg/l (estimation by single wavelength regression is not possible). DOC and HoDOC covaried strongly and could not be estimated independently based on absorbances; HoDOC varied only between 61% and 81% of the DOC. Partly for this reason, an attempt to estimate the HoDOC/DOC ratio based on specific absorbance spectra (absorbance units per mg/l of total DOC) was little successful. Partly, however, this problem resulted from the fact that both HoDOC and HiDOC fractions had a considerable UV absorptivity, which was not consistent between samples. |
| Databáze: | OpenAIRE |
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