免耕对华北平原潮土N_2O和CO_2排放的影响  

Effects of Non-Tillage on N_2O and CO_2 Emissions From Sandy Loam Soil in the North China Plain.

作　　者：蔡延江[1,2] 丁维新[1] 朱安宁[1] 张佳宝[1] 

机构地区：[1]中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室,江苏南京210008 [2]中国科学院研究生院,北京100049

出　　处：《生态与农村环境学报》2011年第5期1-6,共6页Journal of Ecology and Rural Environment

基　　金：国家自然科学基金(40971134);中国科学院知识创新重要方向性项目(KZCX2-YW-439)

摘　　要：采用静态箱-气相色谱法研究了免耕和常规耕作下玉米生长季华北平原潮土N2O和CO2的排放特征。结果表明,免耕土壤N2O累积排放量(以N2O-N计,下同)为0.31 kg.hm-2,略高于常规耕作土壤的0.27 kg.hm-2,两者没有显著差异。灌水、强烈降水或连续阴天会诱发土壤大量排放N2O,免耕处理N2O排放峰值(28.1～38.4μg.m-2.h-1)高于常规耕作处理(18.6～25.7μg.m-2.h-1)。免耕处理CO2累积排放量(以CO2-C计,下同)为1 880 kg.hm-2,显著高于常规耕作土壤的1 333 kg.hm-2。土壤N2O和CO2排放通量与土壤温度呈显著指数相关,常规耕作处理下的相关程度更高。To investigate effects of non-tillage on N2O and CO2 emissions in the North China Plain,a field experiment was conducted to measure N2O and CO2 emissions from soil under conventional tillage and soil that had just assumed non-tillage practice,using closed chamber technique and gas chromatography during the maize growing season.Cumulative N2O emission from the non-tillage soil was 0.31 kg·hm-2,just slightly higher than from the tilled soil,being 0.27 kg·hm-2.In contrast,non-tillage significantly increased soil CO2 emission by 41.6% compared to tillage（1 333 kg·hm-2）.N2O emission peaks appeared after irrigation,heavy rainfall or consecutive cloudy days.N2O emission peaks in the non-tillage treatment ranged from 28.1 to 38.4 μg·m-2·h-1,which were greater than those in the tillage treatment（18.6-25.7 μg·m-2·h-1）.N2O and CO2 fluxes in the two tillage systems displayed a significant exponential relationship with soil temperature,and the seasonal variation of N2O and CO2 fluxes could be better explained by soil temperature in tilled soil than in non-tilled soil.

关 键 词：氧化亚氮 二氧化碳 免耕 温室气体 华北平原 潮土 

分 类 号：X142[环境科学与工程—环境科学] X131.3