Spatial variability of nitrous oxide emissions and their soil-related determining factors in an agricultural field.

• Yanai, Junta

• Sawamoto, Takuji

• Oe, Taku

• Kusa, Kanako

• Yamakawa, Keisuke

• Sakamoto, Kazunori

• Naganawa, Takahiko

• Inubushi, Kazuyuki

• Hatano, Ryusuke

• Kosaki, Takashi

抄録

To evaluate spatial variability of nitrous oxide (N2O) emissions and to elucidate their determining factors on a field-scale basis, N2O fluxes and various soil properties were evaluated in a 100- x 100-m onion (Allium cepa L.) field. Nitrous oxide fluxes were determined by a closed chamber method from the one-hundred 10- x 10-m plots. Physical (e.g., bulk density and water content), chemical (e.g., total N and pH), and biological (e.g., microbial biomass C and N) properties were determined from surface soil samples (0–0.1 m) of each plot. Geostatistical analysis was performed to examine spatial variability of both N2O fluxes and soil properties. Multivariate analysis was also conducted to elucidate relationships between soil properties and observed fluxes. Nitrous oxide fluxes were highly variable (average 331 µg N m-2 h-1, CV 217%) and were log–normally distributed. Log-transformed N2O fluxes had moderate spatial dependence with a range of >75 m. High N2O fluxes were observed at sites with relatively low elevation. Multivariate analysis indicated that an organic matter factor and a pH factor of the principal component analysis were the main soil-related determining factors of log-transformed N2O fluxes. By combining multivariate analysis with geostatistics, a map of predicted N2O fluxes closely matched the spatial pattern of measured fluxes. The regression equation based on the soil properties explained 56% of the spatially structured variation of the log-transformed N2O fluxes. Site-specific management to regulate organic matter content and water status of a soil could be a promising means of reducing N2O emissions from agricultural fields.

収録刊行物

• Journal of Environmental Quality

  Journal of Environmental Quality 32 (6), 1965-1977, 2003

  The American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America

詳細情報

• CRID: 1050282677923525888
• NII論文ID: 120000972658
• HANDLE: 2115/27981
• ISSN: 00472425
• 本文言語コード: en
• 資料種別: journal article
• データソース種別:
  • IRDB
  • CiNii Articles