Abstract
In this study, the diurnal and seasonal variations of CO2 fluxes in a subtropical mixed evergreen forest in Ningxiang of Hunan Province, part of the East Asian monsoon region, were quantified for the first time. The fluxes were based on eddy covariance measurements from a newly initiated flux tower. The relationship between the CO2 fluxes and climate factors was also analyzed. The results showed that the target ecosystem appeared to be a clear carbon sink in 2013, with integrated net ecosystem CO2 exchange (NEE), ecosystem respiration (RE), and gross ecosystem productivity (GEP) of −428.8, 1534.8 and 1963.6 g C m−2yr−1, respectively. The net carbon uptake (i.e. the -NEE), RE and GEP showed obvious seasonal variability, and were lower in winter and under drought conditions and higher in the growing season. The minimum NEE occurred on 12 June (−7.4 g C m−2 d−1), due mainly to strong radiation, adequate moisture, and moderate temperature; while a very low net CO2 uptake occurred in August (9 g C m−2 month−1), attributable to extreme summer drought. In addition, the NEE and GEP showed obvious diurnal variability that changed with the seasons. In winter, solar radiation and temperature were the main controlling factors for GEP, while the soil water content and vapor pressure deficit were the controlling factors in summer. Furthermore, the daytime NEE was mainly limited by the water-stress effect under dry and warm atmospheric conditions, rather than by the direct temperature-stress effect.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Aubinet, M., and Coauthors, 2000: Estimates of the annual net carbon and water exchange of forests: The EUROFLUX methodology. Adv. Ecol. Res., 30, 113–175.
Baldocchi, D., and Coauthors, 2001: Fluxnet: A new tool to study the temporal and spatial variability of ecosystem-scale carbon dioxide, water vapor, and energy flux densities. Bull. Amer. Meteor. Soc., 82(11), 2415–2434.
Carrara, A., I. A. Janssens, J. C. Yuste, and R. Ceulemans, 2004: Seasonal changes in photosynthesis, respiration and NEE of a mixed temperate forest. Agricultural and Forest Meteorology, 126, 15–31.
Chen, Z., and Coauthors, 2013: Temperature and precipitation control of the spatial variation of terrestrial ecosystem carbon exchange in the Asian region. Agricultural and Forest Meteorology, 182, 266–276.
Du, Q., H. Liu, J. Feng, and L. Wang, 2014: Effects of different gap filling methods and land surface energy balance closure on annual net ecosystem exchange in a semiarid area of China. Sci. China (D), 57, 1340–1351.
Falge, E., and Coauthors, 2001: Gap filling strategies for defensible annual sums of net ecosystem exchange. Agricultural and Forest Meteorology, 107(1), 43–69.
Farquhar, G. D., and T. D. Sharkey, 1982: Stomatal conductance and photosynthesis. Annu. Rev. Plant Physiol., 33, 317–345.
Gao, Z., D. H. Lenschow, Z. He, and M., Zhou, 2009: Seasonal and diurnal variations in moisture, heat and CO2 fluxes over a typical steppe prairie in Inner Mongolia, China. Hydrol. Earth Syst. Sci., 13, 987–998.
Joo, S. J., S. U. Park, M. S. Park, and C. S. Lee, 2012: Estimation of soil respiration using automated chamber systems in an oak forest at the Nam-San site in seoul. Korea. Sci. Total. Environ., 416, 400–409.
Ju, W. M., J. M. Chen, D. Harvey, and S. Wang, 2007: Future carbon balance of China’s forests under climate change and increasing CO2. Journal of Environmental Management, 85, 538–562.
Le Quéré, C., and Coauthors, 2013: The global carbon budget 1959–2011. Earth System Science Data Discussions, 5, 165–185.
Liu, J. G., and Coauthors, 2013: The long-term field experiment observatory and preliminary analysis of land-atmosphere interaction over hilly zone in the subtropical monsoon region of southern China. Atmos. Oceanic. Sci. Lett., 6, 203–209.
Liu, Y., and Coauthors, 2006: Seasonal dynamics of CO2 fluxes from subtropical plantation coniferous ecosystem. Sci. China (D), 49(Supp. II), 99–109.
Luo, Y., R. Sherry, X. Zhou, and S. Wan, 2009: Terrestrial carboncycle feedback to climate warming: Experimental evidence on plant regulation and impacts of biofuel feedstock harvest. GCB Bioenergy, 1, 62–74.
Lloyd, J., and J. A. Taylor, 1994: On the temperature dependence of soil respiration. Funct. Ecol., 8, 315–323.
Moffat, A., and Coauthors, 2007: Comprehensive comparison of gap-filling techniques for eddy covariance net carbon fluxes. Agricultural and Forest Meteorology, 147, 209–232.
Papale, D., and Coauthors, 2006: Towards a standardized processing of net ecosystem exchange measured with eddy covariance technique: Algorithms and uncertainty estimation. Biogeosciences, 3, 571–583.
Piao, S., J. Fang, P. Ciais, P. Peylin, Y. Huang, S. Sitch, and T. Wang, 2009: The carbon balance of terrestrial ecosystems in China. Nature, 458, 1009–1013.
Reichstein, M., and Coauthors, 2005: On the separation of net ecosystem exchange into assimilation and ecosystem respiration: Review and improved algorithm. Global. Change. Biol., 11(9), 1424–1439.
Song, X., G. Yu, Y. F. Liu, X. M. Sun, Y. M. Lin, and X. F. Wen, 2006: Seasonal variations and environmental control of water use efficiency in subtropical plantation. Sci. China (D), 49(Supp. II), 119–126.
Webb, E. K., G. I. Pearman, and R. Leuning, 1980: Correction of flux measurement for density effects due to heat and water vapor transfer. Quart. J. Roy. Meteor. Soc., 106, 85–100.
Wilczak, J. M., S. Oncley, and S. Stage, 2001: Sonic anemometer tilt correction algorithms. Bound. -Layer Meteor., 99, 127–150.
Xu, Y., Y. Huang, and Y. Li, 2012: Summary of recent climate change studies on the carbon and nitrogen cycles in the terrestrial ecosystem and ocean in China. Adv. Atmos. Sci., 29(5), 1027–1047, doi: 10.1007/s00376-012-1206-9.
Yu, G., Y. L. Fu, X. M. Sun, X. F. Wen, and L. M. Zhang, 2006: Recent progress and future directions of ChinaFLUX. Sci. China (D), 49(Supp. II), 1–23.
Yuan, W., Y. Q. Luo, A. Richardson, R. Oren, and S. Luyssaert, 2009: Latitudinal patterns of magnitude and interannual variability in net ecosystem exchange regulated by biological and environmental variables. Global. Change. Biol., 15, 2905–2920.
Zeng, N., H. F. Qian, C. Roedenbeck, and M. Heimann, 2005: Impact of 1998–2002 midlatitude drought and warming on terrestrial ecosystem and the global carbon cycle. Geophys. Res. Lett., 32, L22709, doi: 10.1029/2005GL024607.
Zhao, L., Y. Li, S. Xu, H. Zhou, S. Gu, G. Yu, and X. Zhao, 2006: Diurnal, seasonal and annual variation in net ecosystem CO2 exchange of an alpine shrubland on Qinghai-Tibetan plateau. Global. Change. Biol., 12, 1940–1953.
Zhao, M. S., and S.W. Running, 2010: Drought-induced reduction in global terrestrial net primary production from 2000 through 2009. Science, 329, 940–943, doi: 10.1126/science.1192666.
Zheng, X. H., and Coauthors, 2008: Quantifying net ecosystem carbon dioxide exchange of a short-plant cropland with intermittent chamber measurements. Global Biogeochemical Cycles, 22, GB3031, doi: 10.1029/2007GB003104.
Zhu, Z. L., X. M. Sun, X. F. Wen, Y. L. Zhou, J. Tian, and G. F. Yuan, 2006: Study on the processing method of nighttime CO2 eddy covariance flux data in ChinaFLUX. Sci. China (D), 49(Supp. II), 36–46.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Jia, B., Xie, Z., Zeng, Y. et al. Diurnal and seasonal variations of CO2 fluxes and their climate controlling factors for a subtropical forest in Ningxiang. Adv. Atmos. Sci. 32, 553–564 (2015). https://doi.org/10.1007/s00376-014-4069-4
Received:
Revised:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00376-014-4069-4