中国生态农业学报2016，Vol.24Issue(9)：1185-1195,11.DOI:10.13930/j.cnki.cjea.151380
不同生物质炭输入水平下旱作农田温室气体排放研究
Effect of different biochar application levels on greenhouse gas emissions in the Loess Plateau semi-arid environment in China
摘要
Abstract
Biochar is a carbon-rich solid product resulting from biomass heated in the absence of oxygen. Biochar application is deemed to have the potential for greenhouse gas mitigation. Dryland farming areas in Northwest China contribute tremendously to greenhouse gas emission. However, little studies have been conducted in the region involving the application of biochar to improve carbon sink and reduce carbon emission, and the optimal biochar application has remained uncertain. The aim of this study was to determine the effects of biochar on methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2) emissions in the semi-arid regions. Observation was done for the whole growth period of spring wheat and the treatments consisted of six different biochar rates — CK (0 t·hm-2), T1 (10 t·hm-2), T2 (20 t·hm-2), T3 (30 t·hm-2), T4 (40 t·hm-2) and T5 (50 t·hm-2) based on Randomized Complete Block design with three replications. The carbon dioxide analyzer and static chamber-gas chromatographic techniques were used to continuously measure and analyze the greenhouse gases fluxes. Soil moisture and temperature were measured simultaneously with gas measurement. The results showed that dry spring field during whole growth period under different biochar treatments were the sources for CH4, N2O and CO2. The trend of different biochar application rates in the average emission flux of CH4 was CK (0.005 7 mg·m-2·h-1) > T1 (0.004 7 mg·m-2·h-1) > T2 (0.003 6 mg·m-2·h-1) > T3 (0.003 3 mg·m-2·h-1) > T4 (0.002 7 mg·m-2·h-1) > T5 (0.000 4 mg·m-2·h-1). Similar trend of average emission flux of N2O were CK (0.230 5 mg·m-2·h-1) > T5 (0.151 3 mg·m-2·h-1) > T1 (0.144 1 mg·m-2·h-1) > T2 (0.135 3 mg·m-2·h-1) > T4 (0.125 0 mg·m-2·h-1) > T3 (0.098 9 mg·m-2·h-1). The average emission fluxes of CO2 were 0.449 2μmol· m-2·s-1 (CK), 0.447 0μmol· m-2·s-1 (T1), 0.430 3μmol· m-2·s-1 (T2), 0.391 4μmol· m-2·s-1 (T3), 0.408 0μmol· m-2·s-1 (T4) and 0.416 4μmol·m-2·s-1 (T5), respectively. The mean emission flux of CH4 reduced with increasing biochar application level. The results also showed that the mean emissions fluxes of N2O and CO2 significantly increased when biochar input exceeded 30 t·hm-2. Soil temperature and moisture were affected by biochar application. Both soil temperatures at 5-15 cm depth and soil moistures at 5-10 cm soil depth in biochar input exceeded 30 t·hm-2 treatments were significantly different from that of those in the other treatments. The ranges of soil temperature and soil moisture for different soil layers under the CK treatment were highest among all treatments. The application of biochar reduced the variation range of soil temperature and soil moisture at different soil layers. CH4 flux was significantly negatively correlated with soil temperature, while significantly positively correlated with soil moisture at 5-10 cm soil depth. The N2O and CO2 fluxes were negatively correlated with soil temperature at 10-15 cm soil depth, however, they were significantly positively correlated with soil temperature at 20-25 cm soil depth. In addition, soil temperature at 15-20 cm soil depth also had significant positive correlation with average N2O flux. Moreover, soil moisture at 0-5 cm soil depth had significant negative correlation with average CH4, N2O and CO2 fluxes. It is concluded that during the crop growth period, reasonable application of biochar could mitigate greenhouse gas emission in dry farmlands in the study area.关键词
旱作农田/生物质炭/排放通量/CH4/N2O/CO2/土壤温度/土壤湿度Key words
Dry farmland/Biochar/Emission flux/Methane/Nitrous oxide/Carbon dioxide/Soil temperature/Soil moisture分类
环境科学引用本文复制引用
宋敏,齐鹏,蔡立群,Stephen Yeboah,张军,张仁陟,武均,谢军红..不同生物质炭输入水平下旱作农田温室气体排放研究[J].中国生态农业学报,2016,24(9):1185-1195,11.基金项目
甘肃省自然科学基金项目(145RJZA204)、国家自然科学基金项目(31160269,31571594)、国家“十二·五”循环农业科技工程(2012BAD14B03)和甘肃省干旱生境作物学重点实验室开放基金课题(GSCS-2012-13)资助* Supported by the Natural Science Foundation of Gansu Province (145RJZA204), the National Natural Science Foundation of China (31160269,31571594), the Project of the Twelfth Five-Year Plan for Circulation of Agricultural Science and Technology (2012BAD14B03), the Open Found of Gansu Provincial Key Lab of Arid Land Crop Science Project (GSCS-2012-13) （145RJZA204）
