Ammonia Volatilization and Deriitrification Losses from an Irrigated Maize-Wheat Rotation Field in the North China Plain  

Ammonia Volatilization and Denitrilfication Losses from an Irrigated Maize-Wheat Rotation Field in the North China Plain

作　　者：ZHANGYu-Ming CHENDe-Li ZHANGJia-Bao R.EDIS HUChun-Sheng ZHUAn-Ning 

机构地区：[1]InstituteofGeneticsandDevelopmentalBiology,ChineseAcademyofSciences,Shijiazhuang050021（China） [2]DepartmentofResourceManagementandHorticulture,InstituteofLandandFoodResource,theUniversityofMel-bourne,Parkville3052,Victoria（Australia） [3]InstituteofSoilScience,ChineseAcademyofSciences,Nanjing210008（China）

出　　处：《Pedosphere》2004年第4期533-540,共8页土壤圈（英文版）

基　　金：Project supported by the Knowledge Innovation Program of the Chinese Academy of Sciences (No. KZCX2-413-3);the National Key Basic Research Support Foundation (NKBRSF) of China (No. G1999011803) ; the Australian Centre for

摘　　要：Ammonia (NH3) volatilization, denitrification loss, and nitrous oxide (N2O) emission were investigated from an irrigated wheat-maize rotation field on the North China Plain, and the magnitude of gaseous N loss from denitrification and NH3 volatilization was assessed. The micrometeorological gradient diffusion method in conjunction with a Bowen Ratio system was utilized to measure actual NH3 fluxes over a large area, while the acetylene inhibition technique (intact soil cores) was employed for measurement of denitrification losses and N2O emissions. Ammonia volatilization loss was 26.62% of the applied fertilizer nitrogen (N) under maize, while 0.90% and 15.55% were lost from the wheat field at sowing and topdressing, respectively. The differences in NH3 volatilization between different measurement events may be due to differences between the fertilization methods, and to differences in climatic conditions such as soil temperature.Denitrification losses in the fertilized plots were 0.67%-2.87% and 0.31%-0.49% of the applied fertilizer N under maize and wheat after subtracting those of the controls, respectively. Nitrous oxide emissions in the fertilized plots were approximately 0.08%-0.41% and 0.26%-0.34% of the applied fertilizer N over the maize and wheat seasons after subtracting those of the controls, correspondingly. The fertilizer N losses due to NH3 volatilization were markedly higher than those through denitrification and nitrous oxide emissions. These results indicated that NH3 volatilization was an important N transformation in the crop-soil system and was likely to be the major cause of low efficiencies with N fertilizer in the study area. Denitrification was not a very important pathway of N fertilizer loss, but did result in important evolution of the greenhouse gas N2O and the effect of N2O emitted from agricultural fields on environment should not be overlooked.Ammonia (NH_3) volatilization, denitrification loss, and nitrous oxide (N2O)emission were investigated from an irrigated wheat-maize rotation field on the North China Plain,and the magnitude of gaseous N loss from denitrification and NH_3 volatilization was assessed. Themicrometeorological gradient diffusion method in conjunction with a Bowen Ratio system was utilizedto measure actual NH_3 fluxes over a large area, while the acetylene inhibition technique (intactsoil cores) was employed for measurement of denitrification losses and N_2O emissions. Ammoniavolatilization loss was 26.62% of the applied fertilizer nitrogen (N) under maize, while 0.90% and15.55% were lost from the wheat field at sowing and topdressing, respectively. The differences inNH_3 volatilization between different measurement events may be due to differences between thefertilization methods, and to differences in climatic conditions such as soil temperature.Denitrification losses in the fertilized plots were 0.67%— 2.87% and 0.31%— 0.49% of the appliedfertilizer N under maize and wheat after subtracting those of the controls, respectively. Nitrousoxide emissions in the fertilized plots were approximately 0.08%— 0.41% and 0.26%— 0.34% of theapplied fertilizer N over the maize and wheat seasons after subtracting those of the controls,correspondingly. The fertilizer N losses due to NH_3 volatilization were markedly higher than thosethrough denitrification and nitrous oxide emissions. These results indicated thatNH_3 volatilizationwas an important N transformation in the crop-soil system and was likely to be the major cause oflow efficiencies with N fertilizer in the study area. Denitrification was not a very importantpathway of N fertilizer loss, but did result in important evolution of the greenhouse gas N_2O andthe effect of N_2O emitted from agricultural fields on environment should not be overlooked.

关 键 词：ammonia volatilization DENITRIFICATION gaseous N loss N_2O emission 

分 类 号：S143.1[农业科学—肥料学]