TY - JOUR
T1 - Accumulation of nitrous oxide and depletion of oxygen in seasonally frozen soils in northern Japan - Snow cover manipulation experiments
AU - Yanai, Yosuke
AU - Hirota, Tomoyoshi
AU - Iwata, Yukiyoshi
AU - Nemoto, Manabu
AU - Nagata, Osamu
AU - Koga, Nobuhisa
N1 - Funding Information:
The authors thank K. Shibata, Y. Itoh, Y. Kato, S. Yanagiya, M. Yamazaki, K. Shibuya, S. Saito, T. Takakura, T. Hirao, M. Takasugi, F. Yagasaki, T. Emura and M. Yamasaki for field and laboratory assistance; M. Yoh for the determination of the O 2 concentration; K. Okazaki for the determination of the mineral nitrogen; T. Tokida, H. Tsuruta, M. Ono, S. Hasegawa, T. Hirano and A. Sugimoto for fruitful discussions. This research received the financial support of the Environment Research and Technology Development Fund (A-087 to T.H.) of the Ministry of the Environment, Japan. Y.Y. was supported by a Research Fellowship for Young Scientists from the Japanese Society for the Promotion of Science (20-4158).
PY - 2011/9
Y1 - 2011/9
N2 - It has been suggested that soil-thawing and snow-melting are critical triggers for vigorous emissions of nitrous oxide (N2O) from soils in cold regions. However, because soil freezing is affected by air temperature and snow cover, accurate predictions that estimate subsequent emissions of this important greenhouse gas are difficult to make. In this study, we measured in situ soil gas N2O and oxygen (O2) concentrations at two experimental sites in northern Japan over the period of a year, from November 2008 to October 2009, to clarify the factors stimulating N2O production in soil at low temperatures. The sites were N-fertilized bare arable lands with different soil frost depths and snowmelt rates, according to the snow cover management imposed. Winter-to-spring net N2O fluxes, ranging from -0.10 to 1.95kgN2O-N ha-1, were positively correlated with the annual maximum soil frost depth (ranging from 0.03 to 0.41m; r=0.951). In the plots with deeper maximum soil frost, winter-to-spring N2O fluxes represented 58% to 85% of the annual values. Soil N2O production was stimulated when the soil frost depth was greater than 0.15m or the daily mean soil temperature at 0.05-m depth was below -2.0°C. In the soil with the greatest frost depth, soil gas N2O concentrations at the depth of 0.10m peaked at 46ppm when soil gas O2 concentrations fell down to 0.12m3m-3 under soil temperature below 0.0°C. Snowmelt acceleration had no stimulating effect on N2O production in the soil during the winter-to-spring period.
AB - It has been suggested that soil-thawing and snow-melting are critical triggers for vigorous emissions of nitrous oxide (N2O) from soils in cold regions. However, because soil freezing is affected by air temperature and snow cover, accurate predictions that estimate subsequent emissions of this important greenhouse gas are difficult to make. In this study, we measured in situ soil gas N2O and oxygen (O2) concentrations at two experimental sites in northern Japan over the period of a year, from November 2008 to October 2009, to clarify the factors stimulating N2O production in soil at low temperatures. The sites were N-fertilized bare arable lands with different soil frost depths and snowmelt rates, according to the snow cover management imposed. Winter-to-spring net N2O fluxes, ranging from -0.10 to 1.95kgN2O-N ha-1, were positively correlated with the annual maximum soil frost depth (ranging from 0.03 to 0.41m; r=0.951). In the plots with deeper maximum soil frost, winter-to-spring N2O fluxes represented 58% to 85% of the annual values. Soil N2O production was stimulated when the soil frost depth was greater than 0.15m or the daily mean soil temperature at 0.05-m depth was below -2.0°C. In the soil with the greatest frost depth, soil gas N2O concentrations at the depth of 0.10m peaked at 46ppm when soil gas O2 concentrations fell down to 0.12m3m-3 under soil temperature below 0.0°C. Snowmelt acceleration had no stimulating effect on N2O production in the soil during the winter-to-spring period.
UR - http://www.scopus.com/inward/record.url?scp=80051473804&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=80051473804&partnerID=8YFLogxK
U2 - 10.1016/j.soilbio.2010.06.009
DO - 10.1016/j.soilbio.2010.06.009
M3 - Article
AN - SCOPUS:80051473804
VL - 43
SP - 1779
EP - 1786
JO - Soil Biology and Biochemistry
JF - Soil Biology and Biochemistry
SN - 0038-0717
IS - 9
ER -