Science Alert
Curve Top
International Journal of Agricultural Research
  Year: 2009 | Volume: 4 | Issue: 1 | Page No.: 1-16
DOI: 10.3923/ijar.2009.1.16
Facebook Twitter Digg Reddit Linkedin StumbleUpon E-mail

Nitrous Oxide (N2O) Emissions from a Japanese Lowland Soil Cropped to Onion: III. Relationship with Soil Physical Properties

Nsalambi V. Nkongolo, Kanta Kuramochi and Hatano Ryusuke

We studied the spatial variability of soil physical properties and related these properties to N2O emissions. The study was conducted in a Japanese lowland soil cropped to onion in Mikassa, Hokkaido (Japan). N2O emissions measurements and soil sampling were conducted along a 100x100 m (1999) and 60x60 m (2000) grids with samples taken at 10 m spacing. Air samples for N2O determination were collected using the closed-chamber technique. Air samples were stored in vial bottles for analysis with a gas chromatograph with electron capture detector within 24 h after sampling. Soil samples were collected with a 5 cm diameter and a 5 cm height cylinder. Soil physical properties measured were soil temperature (T), bulk density (Ï?b), volumetric water content (θv), gravimetric water content (θg), air-filled porosity (fa), total pore space (TPS), relative gas diffusivity coefficient (Ds/Do) and the pore tortuosity factor (Ï„). Results showed that N2O emissions were highest in 1999 as compared to 2000. They were fitted to a linear variogram in 1999 while they responded to a spherical variogram model in 2000. Positive first degree surface trends were also found in N2O emissions data in both years and the removal of these trends did not change variogram models, but significantly improved them by increasing the R2 and Q values. Soil physical properties responded to a range of variograms, from linear to spherical models. Detrending soil physical properties either increased (T) or decreased (θv) the range and R2 values. Soil T, Ï„, Ds/Do, WFPS were significantly correlated with N2O emissions. N2O emissions and soil properties varied considerably in space and time. More studies are needed to identify other soil physical properties which might better correlate with N2O emissions, besides the traditional T and WFPS.
PDF Fulltext XML References Citation Report Citation
How to cite this article:

Nsalambi V. Nkongolo, Kanta Kuramochi and Hatano Ryusuke, 2009. Nitrous Oxide (N2O) Emissions from a Japanese Lowland Soil Cropped to Onion: III. Relationship with Soil Physical Properties. International Journal of Agricultural Research, 4: 1-16.

DOI: 10.3923/ijar.2009.1.16






Curve Bottom