@article{oai:rakuno.repo.nii.ac.jp:00000393,
 author = {KATAYANAGI, Nobuko and SAWAMOTO, Takuji and 澤本, 卓治 and HAYAKAWA, Atsushi and HATANO, Ryusuke},
 issue = {4},
 journal = {Soil science and plant nutrition},
 month = {Aug},
 note = {Article, We developed a new and improved method, the ‘high-emission-incorporation (HEI) method’, for estimating soil nitrous oxide (N_2O) emission rates at a watershed level based on nitrogen (N) input (consisting of fertilizer, manure, slurry and excreta N) and N surplus (calculated by subtracting the amount of crop yield and consumed N from the N input) of different sites in a livestock farm located in a watershed. The main characteristic of this method is the inclusion of extremely high N_2O emission rates, ‘outlier’, which are normally excluded from estimation. High N_2O emission rates were estimated using the regression model obtained from the measured N_2O values and the amounts of N surplus; normal N_2O emission rates were estimated using the regression model obtained from the measured values and the amount of N input. The probability of occurrence of a high flux was used to incorporate calculated high and normal N_2O emissions into one. The annual N_2O emission rate from the livestock farm in the watershed (467 ha), estimated using the HEI method, was 1156 ± 147 kg N year^<−1> over a 5-year period. The annual N_2O emission rates calculated using the site-specific emission factor (EF = 0.0789) and the emission factor of the Intergovernmental Panel on Climate Change (EF = 0.01) were 1838 ± 585 kg N year^<−1> and 673 (522-1103) kg N year^<−1>, respectively. The estimated value using the measure-and-multiply method, in which each land-use area is multiplied by the representative emission rate for each land-use type, was 964 (509-1610) kg N year^<−1>. The N_2O emission rates estimated by our newly developed method were consistent with the values calculated by the measure-and-multiply method and offered improvement over this measure because the new measure can also predict future N_2O emission rates from the watershed.},
 pages = {590--598},
 title = {New method for the estimation of nitrous oxide emission rates from an agricultural watershed},
 volume = {55},
 year = {2009}
}