| Autor: |
Makarov, M. I., Malysheva, T. I., Menyailo, O. V., Soudzilovskaia, N. A., Van Logtestijn, R. S. P., Cornelissen, J. H. C. |
| Předmět: |
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| Zdroj: |
European Journal of Soil Science; May2015, Vol. 66 Issue 3, p417-426, 10p |
| Abstrakt: |
Determination of the labile soil carbon ( C) and nitrogen ( N) fractions and measurement of their isotopic signatures ( δ13C and δ15N) has been used widely for characterizing soil C and N transformations. However, methodological questions and comparison of results of different authors have not been fully solved. We studied concentrations and δ13C and δ15N of salt-extractable organic carbon ( SEOC), inorganic ( N-NH4+ and N-NO3−) and organic nitrogen ( SEON) and salt-extractable microbial C ( SEMC) and N ( SEMN) in 0.05 and 0.5 m K2SO4 extracts from a range of soils in Russia. Despite differences in acidity, organic matter and N content and C and N availability in the studied soils, we found consistent patterns of effects of K2SO4 concentration on C and N extractability. Organic C and N were extracted 1.6-5.5 times more effectively with 0.5 m K2SO4 than with 0.05 m K2SO4. Extra SEOC extractability with greater K2SO4 concentrations did not depend on soil properties within a wide range of pH and organic matter concentrations, but the effect was more pronounced in the most acidic and organic-rich mountain Umbrisols. Extractable microbial C was not affected by K2SO4 concentrations, while SEMN was greater when extracted with 0.5 m K2SO4. We demonstrate that the δ13C and δ15N values of extractable non-microbial and microbial C and N are not affected by K2SO4 concentrations, but use of a small concentration of extract (0.05 m K2SO4) gives more consistent isotopic results than a larger concentration (0.5 m). [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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