Effect of organic matter application on N₂O, NO, and NO₂ fluxes from an Andisol field

We used an automated flux monitoring system to measure N 2 O, NO, and NO 2 fluxes from an Andisol field between May 1999 and September 2000. Pac choi and spinach were cultivated for 1.5 months in 1999 and 2000, respectively. We applied 15 g N m −2 of oilcake, cattle manure, fishmeal, dried cattle excreta, or urea to each plot. N 2 O and NO emissions from organic plots over the cultivation period were 2.55 mg N m −2 to 35.2 mg N m −2 , and 2.48 mg N m −2 to 22.5 mg N m −2 , respectively. Those from the urea plot were 10.9 mg N m −2 to 21.1 mg N m −2 , and 52.0 mg N m −2 to 105 mg N m −2 , respectively. We estimated that N 2 O emission from organic fertilizer is equivalent to that from chemical fertilizer application on Japanese Andisol field.