13N, a radionuclide with a half-life of 10 min, has been used for a variety of purposes in medical and agricultural research and in a variety of forms, e.g. as 13N2 for study of nitrogen fixation and translocation in plants, 13NH4 and 13NO3 for studying plant nitrogen uptake, 13NO3 for studying denitrification, and 13N2O in medical research (Straatmann, 1977). The advantages of 13N are the ease of detection, measurement and identification of volatile products, and the short half-life that permits several consecutive experiments on the same material. The very small quantities of the label used ensure that there is no alternation of equilibrium reactions,but the short half-life does mean that experiments must be of simple design and must be conducted with minimum preparation of substrate and near the production source of the isotope. Nitrogen flux in soil due to dissimilatory denitrification, a form of anaerobic respiration, is a major component of the nitrogen cycle (Nielsen and MacDonald, 1978) and, in the experiments reported, 13N was used to examine the movement of the major components of the cycle in a relatively undisturbed soil and the evolution of gases by different bacterial cultures and soil cores.
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- The Measurement of Denitrification in Soil, Using 13NO3
J. D. Stout
R. D. More
- Springer Berlin Heidelberg