Spatial variability of N2O emissions and soil parameters of an arable siltloam - a field study

The spatial in situ variability of soil N2O emissions (measured by micro-ch ambers, radius 0.033 m), N2O content, water content, NO3-, NH4+, inorganic carbon and organic carbon concentrations was investigated on a silt loam by means of geostatistical methods and nonparametric statistics. The sampling grid consisted of different spacings between sampling points which ranged from 0.1 m to 50 m. There were no significant correlations between N2O emis sions and soil parameters (P>0.1) when all the sampling points were conside red. In the centre of the grid a "hot area" was localized with significantl y higher N2O emissions, and NO, and NH4+ concentrations (P less than or equ al to 0.05). Within this hot area the N2O soil content significantly correl ated with N2O emissions (P less than or equal to 0.05). When semiovariogram s were computed without data of the hot area samples, N2O emissions showed a weak spatial correlation (range: 4.3 m). The calculations including all d ata led to pure nugget effects for all parameters except for soil water con tent (range >40 m) and N2O soil content (range 16.4 m).