Uncertainty analysis of eddy flux measurements in typical ecosystems of ChinaFLUX

	Uncertainty analysis of eddy flux measurements in typical ecosystems of ChinaFLUX
	He, Honglin ; Liu, Min ; Sun, Xiaomin ; Zhang, Li ; Luo, Yiqi ; Wang, Huiming ; Han, Shijie ; Zhao, Xinquan ; Shi, Peili ; Wang, Yanfen ; Ouyang, Zhu ; Yu, Guirui
刊名	ECOLOGICAL INFORMATICS ; He, HL; Liu, M; Sun, XM; Zhang, L; Luo, YQ; Wang, HM; Han, SJ; Zhao, XQ; Shi, PL; Wang, YF; Ouyang, Z; Yu, GR.Uncertainty analysis of eddy flux measurements in typical ecosystems of ChinaFLUX,ECOLOGICAL INFORMATICS,2010,5(6):492-502
	2010-11-01
英文摘要	Fluxes of CO(2) (FCO(2)) and energy (latent heat, LE; sensible heat. H) exchange between ecosystems and atmosphere, as measured by the eddy covariance technique, represent a fundamental data source for global-change research. However, little is known about the uncertainties of flux measurements at an ecosystem level in China. Here, we use data from six eddy covariance tower sites in ChinaFLUX, including two forested sites, three grassland sites, and one agricultural site, to conduct a cross-site analysis of random flux errors (RFEs) of FCO(2). LE, and H. By using the daily-differencing approach, paired observations are obtained to characterize the random error in these measurements. Our results show that: (1) The RFEs of FCO(2), LE, and H in different ecosystems of ChinaFLUX closely follow a double-exponential (Laplace) distribution, presumably due to a superposition of Gaussian distribution for high flux magnitude. (2) The RFEs of FCO(2), LE, and H are not homogeneous and appear to be a linear function of flux magnitude. (3) Except for H. the RFEs of FCO(2) and LE exhibit a distinct seasonal pattern. For FCO(2), the dependence of RFEs on wind speed varies somewhat according to vegetation type, whereas for LE and H, there is no such dependence. The effect of temperature on RFEs is not statistically significant (P<0.05). Both the distribution and the relationship of RFEs with flux magnitude in ChinaFLUX are essentially in accord with those in AmeriFlux and CarboEurope. (C) 2010 Elsevier B.V. All rights reserved.; Fluxes of CO2 (FCO2) and energy (latent heat, LE; sensible heat. H) exchange between ecosystems and atmosphere, as measured by the eddy covariance technique, represent a fundamental data source for global-change research. However, little is known about the uncertainties of flux measurements at an ecosystem level in China. Here, we use data from six eddy covariance tower sites in ChinaFLUX, including two forested sites, three grassland sites, and one agricultural site, to conduct a cross-site analysis of random flux errors (RFEs) of FCO2. LE, and H. By using the daily-differencing approach, paired observations are obtained to characterize the random error in these measurements. Our results show that: (1) The RFEs of FCO2, LE, and H in different ecosystems of ChinaFLUX closely follow a double-exponential (Laplace) distribution, presumably due to a superposition of Gaussian distribution for high flux magnitude. (2) The RFEs of FCO2, LE, and H are not homogeneous and appear to be a linear function of flux magnitude. (3) Except for H. the RFEs of FCO2 and LE exhibit a distinct seasonal pattern. For FCO2, the dependence of RFEs on wind speed varies somewhat according to vegetation type, whereas for LE and H, there is no such dependence. The effect of temperature on RFEs is not statistically significant (P<0.05). Both the distribution and the relationship of RFEs with flux magnitude in ChinaFLUX are essentially in accord with those in AmeriFlux and CarboEurope. (C) 2010 Elsevier B.V. All rights reserved.
内容类型	期刊论文
源URL	[http://ir.nwipb.ac.cn//handle/363003/1630]
专题	西北高原生物研究所_中国科学院西北高原生物研究所
推荐引用方式 GB/T 7714	He, Honglin,Liu, Min,Sun, Xiaomin,et al. Uncertainty analysis of eddy flux measurements in typical ecosystems of ChinaFLUX[J]. ECOLOGICAL INFORMATICS, He, HL; Liu, M; Sun, XM; Zhang, L; Luo, YQ; Wang, HM; Han, SJ; Zhao, XQ; Shi, PL; Wang, YF; Ouyang, Z; Yu, GR.Uncertainty analysis of eddy flux measurements in typical ecosystems of ChinaFLUX,ECOLOGICAL INFORMATICS,2010,5(6):492-502,2010.
APA	He, Honglin.,Liu, Min.,Sun, Xiaomin.,Zhang, Li.,Luo, Yiqi.,...&Yu, Guirui.(2010).Uncertainty analysis of eddy flux measurements in typical ecosystems of ChinaFLUX.ECOLOGICAL INFORMATICS.
MLA	He, Honglin,et al."Uncertainty analysis of eddy flux measurements in typical ecosystems of ChinaFLUX".ECOLOGICAL INFORMATICS (2010).