Static opaque chamber-based technique for determination of net exchange of CO2 between terrestrial ecosystem and atmosphere

编号 zgly0000335344

文献类型 期刊论文

文献题名 Static opaque chamber-based technique for determination of net exchange of CO2 between terrestrial ecosystem and atmosphere

学科分类 220.1060;森林生态学

作者 ZOUJianwen  HUANGYao  ZHENGXunhua  WANGYuesi  CHENYuquan 

作者单位 CollegeofResourcesandEnvironmentalSciences  NanjingAgriculturalUniversity  Nanjing210095  China 

母体文献 Chinese Science Bulletin;中国科学通报: 英文版 

年卷期 2004,49(4)

页码 381-388

年份 2004 

分类号 Q148 

关键词 二氧化碳  陆地生态系统  碳循环  大气层 

文摘内容 Terrestrial carbon cycling is one of the hotspots in global change issues. In this paper, we presented the rationale for determination of net exchange of CO2 between terrestrial and the atmosphere (NEE) and the methods for measuring several relevant components. Three key processes for determination of NEE were addressed, including the separation of shoot autotrophic respiration from total CO2 emissions of the ecosystem, the partition of root respiration from soil CO2 efflux, and the quantification of rhizodeposilion C from NPP. With an understanding of the processes involved in the CO2 exchange between terrestrial and the atmosphere, we estimated NEE of rice ecosystem in Nanjing based on field measurements of CO2 emissions and several relevant biotic components as well as abiotic factors. The field measurements of CO2 emissions were made over the rice-growing seasons in 2001 and 2002 with the static opaque chamber method. Calculations indicated that the seasonal pattern of NEE is comparable for two seasons. Either net carbon emission or fractional carbon fixation occurred during 3 weeks after rice transplanting and thereafter net carbon fixation appeared with an increasing trend as rice growing. Higher net carbon fixation occurred in the rice developmental period from elongating to heading. A decline trend in the fixation was documented after rice heading. The mean daily NEE was -6.06 gC·m^-2 in 2001 season and -7.95 gC·m^-2 in 2002 season, respectively. These values were comparable to the results obtained by Campbell et al. who made field measurements with the Bowen ratio-energy balance technique in irrigated rice, Texas USA. Moreover, the mean daily NEE in this study was also comparable to the values obtained from a Japanese rice paddy with the eddy covariance method under the similar water regime, either drainage course or waterlogged. It is concluded that NEE determined by the static opaque chamber method is comparable and in agreement with those measured by Bowen ratioenergy balance and eddy covariance methods。