caa a22 4500 477061265 CHVBK 20180405111401.0 cr unu---uuuuu 170330e19960301xx s 000 0 eng 10.1007/BF00055157 doi (NATIONALLICENCE)springer-10.1007/BF00055157 Flux between soil and atmosphere, vertical concentration profiles in soil, and turnover of nitric oxide: 2. Experiments with naturally layered soil cores [Elektronische Daten] [Jutta Rudolph, Ralf Conrad] Intact soils cores were taken with a stainless steel corer from a sandy podzol and a loamy luvisol, and used to measure the flux (J) of NO between soil and atmosphere and the vertical profile of the NO mixing ratios (m) in the soil atmosphere, both as function of the NO mixing ratio (m a) in the atmosphere of the headspace. These measurements were repeated after stepwise excavation of the soil column from the top, e.g. by removing the upper 2 cm soil layer. The gaseous diffusion coefficients of NO in the soil cores were either computed from soil porosity or were determined from experiments using SF6. The NO fluxes (J) that were actually measured at the soil surface were compared to the fluxes which were calculated either from the vertical NO profiles (J c ) or from the NO production and uptake rates (J m ) determined in the excavated soil samples. In the podzol, the actually measured (J) and the calculated (J m , Jm) NO fluxes agreed within a factor of 2. In the luvisol, the measured NO fluxes (J) and those calculated from the vertical NO profiles (J c ) also agreed well, but in the upper 6 cm soil layer the NO fluxes (J m ) calculated from NO production and uptake rates were up to 7 times higher than the measured NO fluxes. This poor agreement was probably due to the inhomogeneous distribution of NO production and consumption processes and the change of diffusivities within the top layers of the luvisol. Indeed, the luvisol showed a pronounced maximum of the NO mixing ratios at about 6 cm depth, whereas the podzol column exhibited a steady and exponential decrease of the NO mixing ratios with depth. The inhomogeneities in the luvisol were confirmed by incubation of the soil cores under anoxic conditions. This treatment resulted in production of NO at several depths indicating a zonation of increased potential activities within the luvisol profile which may have biased the modelling of the NO surface flux from turnover measurements in soil samples. Inhomogeneities could be achieved even in homogenized soil by fertilization with nitrate solution. Kluwer Academic Publishers, 1996 NO emission nationallicence NO production nationallicence NO consumption nationallicence NO vertical profile nationallicence NO compensation concentration nationallicence relaxation depth nationallicence soil atmosphere nationallicence diffusion model nationallicence diffusion coefficient nationallicence gas flow nationallicence luvisol, podzol nationallicence fertilization nationallicence anoxic condition nationallicence Rudolph Jutta Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch-Str., D-35043, Marburg, Germany aut Conrad Ralf Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch-Str., D-35043, Marburg, Germany aut Journal of Atmospheric Chemistry Kluwer Academic Publishers; gopher://gopher.wkap.nl 23/3(1996-03-01), 275-300 0167-7764 23:3<275 1996 23 10874 https://doi.org/10.1007/BF00055157 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00055157 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Rudolph Jutta Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch-Str., D-35043, Marburg, Germany aut NATIONALLICENCE 700 1- Conrad Ralf Max-Planck-Institut für terrestrische Mikrobiologie, Karl-von-Frisch-Str., D-35043, Marburg, Germany aut NATIONALLICENCE 773 0- Journal of Atmospheric Chemistry Kluwer Academic Publishers; gopher://gopher.wkap.nl/ 23/3(1996-03-01), 275-300 0167-7764 23:3<275 1996 23 10874 Metadata rights reserved Springer special CC-BY-NC licence nationallicence SWISSBIB 477061265 BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer