@article{oai:nipr.repo.nii.ac.jp:00002516,
 author = {Ueyama,Masahito and Harazono,Yoshinobu and Okada,Ryo and Nojiri,Atsushi and Ohtaki,Eiji and Miyata,Akira},
 journal = {Memoirs of National Institute of Polar Research. Special issue},
 month = {Mar},
 note = {P(論文), Methane (CH_4) flux at a black spruce forest in central Alaska was determined by applying the three types of modified gradient method. One type used the eddy diffusivity obtained by CO_2 flux and CO_2 gradient. Others established the flux gradient relationship assuming Monin-Obukhov similarity. The wind speed and temperature profile functions were corrected for the influence of the roughness sublayer, and then applied to the modified gradient methods. More than 70% of the data were rejected by the strict quality control and a continental climate, such as calm wind. Although the diurnal variations of CH_4 flux by the three methods were different, the seasonal variation showed similar tendency; a weak emission on snowpack, an obvious emission around spring thaw, and CH_4 uptake in the late growing season. As calculated CH_4 flux was in the same range as with previous studies conducted by the chamber measurement.},
 pages = {156--167},
 title = {Micrometeorological measurements of methane flux at a boreal forest in central Alaska},
 volume = {59},
 year = {2006}
}