References

BGD

Biogeosciences Discussions

BGD

1810-6285

Copernicus GmbH

Göttingen, Germany

10.5194/bgd-8-7671-2011

Use of the isotope flux ratio approach to investigate the C18O16O and 13CO2 exchange near the floor of a temperate deciduous forest

Santos

¹ Wagner-Riddle

¹ Lee

² Warland

¹ Brown

¹ Staebler

³ Bartlett

⁴ Kim

School of Environmental Sciences, Guelph, ON, N1G 2W1, Canada

School of Forestry and Environmental Studies, Yale University, New Haven, CT, USA

Air Quality Research Division, Environment Canada, Toronto, ON, Canada

Climate Research Division, Environment Canada, Toronto, ON, Canada

01 08 2011

8 4 7671 7712

This is an open-access article ditributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

This article is available from http://www.biogeosciences-discuss.net/8/7671/2011/bgd-8-7671-2011.html

The full text article is available as a PDF file from http://www.biogeosciences-discuss.net/8/7671/2011/bgd-8-7671-2011.pdf

Stable isotopologues of CO2, such as 13CO2 and C18O16O, have been used to study the CO2 exchange between land and atmosphere. The advent of new measuring techniques has allowed near-continuous measurements of stable isotopes in the air. These measurements can be used with micrometeorological techniques, providing new tools to investigate the isotope exchange in ecosystems. The objectives of this study were to evaluate the use of the isotope flux ratio method (IFR) near the forest floor of a temperate deciduous forest and to study the temporal dynamics of δ18O of CO2 flux near the forest floor by comparing IFR estimates with estimates of δ18O of net soil CO2 flux provided by an analytical model. Mixing ratios of 12C16O2, 13CO2 and C16O18O were measured within and above a temperate deciduous forest, using the tunable diode laser spectroscopy technique. The half-hourly compositions of the CO2 flux near the forest floor (δ13CF and δ18OF) were compared with estimates provided by a modified Keeling plot technique (mKP) and by a Lagrangian dispersion analysis (WT analysis). The mKP and IFR δ18OF estimates showed good agreement (slope = 1.03 and correlation, R2 = 0.80). The δ13CF estimates from the two methods varied in a narrow range of −32.7 and −23.1 &permil;; the mean (±SE) mKP and IFR δ13CF values were −27.5 ‰ (±0.2) and −27.3 &permil; (±0.1), respectively, and were statistically identical (p > 0.05). WT analysis and IFR δ18OF estimates showed better correlation (R2 = 0.37) when only turbulent periods (u&ast; > 0.6 m s−1) were included in the analysis. The large data capture (~95 % of half-hour periods evaluated) for the IFR in comparison with mKP (27 %) shows that the former provides new opportunities for studying δ18O-CO2 flux dynamics within forest canopies. Values of δ18OF showed large temporal variation, with values ranging from −31.4 &permil; (DOY 208) to −11.2 &permil; (DOY 221). Precipitation events caused substantial variation (~8 &permil;) in δ18OF over a period of approximately 24 h. A diel trend of δ18OF was observed, with more enriched values present during the daytime. Model simulations indicate that the activity of the carbon anhydrase enzyme was very variable during the evaluated period. These simulations indicate that more frequent sampling of δ18O of soil water could improve the estimates of δ18O of net soil CO2 flux.

References 1

Amundson, R., Stern, L., Baisden, T., and Wang, Y.: The isotopic composition of soil and soil-respired CO2, Geoderma, 82, 83–114, 1998.

Baldocchi, D. D. and Meyers, T. P.: Trace gas-exchange above the floor of a deciduous forest 1. Evaporation and CO2 efflux, J. Geophys. Res.-Atmos., 96, 7271–7285, 1991.

Bird, R. B., Stewart, W. E., and Ligthfoot, E. N.: Transport phenomena, Wiley, New York, 2002.

Bowling, D. R., Tans, P. P., and Monson, R. K.: Partitioning net ecosystem carbon exchange with isotopic fluxes of CO2, Glob. Change Biol., 7, 127–145, 2001.

Bowling, D. R., Mcdowell, N. G., Welker, J. M., Bond, B. J., Law, B. E., and Ehleringer, J. R.: Oxygen isotope content of CO2 in nocturnal ecosystem respiration: 2. Short-term dynamics of foliar and soil component fluxes in an old-growth ponderosa pine forest, Global Biogeochem. Cy., 17, 1124, http://dx.doi.org/10.1029/2003GB002082doi:10.1029/2003GB002082, 2003a.

Bowling, D. R., Sargent, S. D., Tanner, B. D., and Ehleringer, J. R.: Tunable diode laser absorption spectroscopy for stable isotope studies of ecosystem-atmosphere CO2 exchange, Agr. Forest Meteorol., 118, 1–19, 2003b.

Bowling, D. R., Burns, S. P., Conway, T. J., Monson, R. K., and White, J. W. C.: Extensive observations of CO2 carbon isotope content in and above a high-elevation subalpine forest, Global Biogeochem. Cy., 19, GB3023, http://dx.doi.org/10.1029/2004GB002394doi:10.1029/2004GB002394, 2005.

Braud, I., Bariac, T., Gaudet, J. P., and Vauclin, M.: Sispat-isotope, a coupled heat, water and stable isotope (HDO and H$_2^18$O) transport model for bare soil. Part I. Model description and first verifications, J. Hydrol., 309, 277–300, 2005.

Brenninkmeijer, C. A. M., Kraft, P., and Mook, W. G.: Oxygen isotope fractionation between CO2 and H2O, Isot. Geosci., 1, 181–190, 1983.

Buchmann, N., Kao, W. Y., and Ehleringer, J.: Influence of stand structure on carbon-13 of vegetation, soils, and canopy air within deciduous and evergreen forests in Utah, United States, Oecologia, 110, 109–119, 1997.

Ciais, P., Tans, P. P., White, J. W. C., Trolier, M., Francey, R. J., Berry, J. A., Randall, D. R., Sellers, P. J., Collatz, J. G., and Schimel, D. S.: Partitioning of ocean and land uptake of CO2 as inferred by $\delta ^13$C measurements from the NOAA climate monitoring and diagnostics laboratory global air sampling network, J. Geophys. Res.-Atmos., 100, 5051–5070, 1995.

Corrsin, S.: Limitations of gradient transport models in random walks and in turbulence, Adv. Geophys., 18A, 25–60, 1974.

Cosby, B. J., Hornberger, G. M., Clapp, R. B., and Ginn, T. R.: A statistical exploration of the relationships of soil-moisture characteristics to the physical-properties of soils, Water Resour. Res., 20, 682–690, 1984.

Cuntz, M., Ciais, P., Hoffmann, G., and Knorr, W.: A comprehensive global three-dimensional model of $\delta ^18$O in atmospheric CO2: 1. Validation of surface processes, J. Geophys. Res.-Atmos., 108, 4527, http://dx.doi.org/10.1029/2002JD003153doi:10.1029/2002JD003153, 2003.

Davidson, E. A., Savage, K., Verchot, L. V., and Navarro, R.: Minimizing artifacts and biases in chamber-based measurements of soil respiration, Agr. Forest Meteorol., 113, 21–37, 2002.

Denmead, O. T. and Bradley, E. F.: On scalar transport in plant canopies, Irrigation Sci., 8, 131–149, 1987.

Dolman, A. J. and Wallace, J. S.: Lagrangian and K-theory approaches in modeling evaporation from sparse canopies, Q. J. Roy. Meteorol. Soc., 117, 1325–1340, 1991.

Ehleringer, J. R. and Osmond, C. B.: Stable isotopes, in: Plant physiological ecology: field methods and instrumentation, edited by: Pearcy, R. W., Ehleringer, J. R., Mooney, H. A., and Rundel, P. W., Chapman and Hall, London, 1989.

Farquhar, G. D. and Cernusak, L. A.: On the isotopic composition of leaf water in the non-steady state, Funct. Plant Biol., 32, 293–303, 2005.

Farquhar, G. D., Ehleringer, J. R., and Hubick, K. T.: Carbon isotope discrimination and photosynthesis, Annu. Rev. Plant Phys., 40, 503–537, 1989.

Farquhar, G. D., Lloyd, J., Taylor, J. A., Flanagan, L. B., Syvertsen, J. P., Hubick, K. T., Wong, S. C., and Ehleringer, J. R.: Vegetation effects on the isotope composition of oxygen in atmospheric CO2, Nature, 363, 439–443, 1993.

Flanagan, L. B., Brooks, J. R., Varney, G. T., and Ehleringer, J. R.: Discrimination against C$^18$O$^16$O during photosynthesis and the oxygen isotope ratio of respired CO2 in boreal forest ecosystems, Global Biogeochem. Cy., 11, 83–98, 1997.

Flanagan, L. B., Kubien, D. S., and Ehleringer, J. R.: Spatial and temporal variation in the carbon and oxygen stable isotope ratio of respired CO2 in a boreal forest ecosystem, Tellus B, 51, 367–384, 1999.

Fung, I., Field, C. B., Berry, J. A., Thompson, M. V., Randerson, J. T., Malmstrom, C. M., Vitousek, P. M., Collatz, G. J., Sellers, P. J., Randall, D. A., Denning, A. S., Badeck, F., and John, J.: Carbon 13 exchanges between the atmosphere and biosphere, Global Biogeochem. Cy., 11, 507–533, 1997.

Gillon, J. and Yakir, D.: Influence of carbonic anhydrase activity in terrestrial vegetation on the $^18$O content of atmospheric CO2, Science, 291, 2584–2587, 2001.

Griffis, T. J., Baker, J. M., Sargent, S. D., Tanner, B. D., and Zhang, J.: Measuring field-scale isotopic CO2 fluxes with tunable diode laser absorption spectroscopy and micrometeorological techniques, Agr. Forest Meteorol., 124, 15–29, 2004.

Griffis, T. J., Baker, J. M., and Zhang, J.: Seasonal dynamics and partitioning of isotopic CO2 exchange in C3/C4 managed ecosystem, Agr. Forest Meteorol., 132, 1–19, 2005a.

Griffis, T. J., Lee, X., Baker, J. M., Sargent, S. D., and King, J. Y.: Feasibility of quantifying ecosystem-atmosphere C$^18$O$^16$O exchange using laser spectroscopy and the flux-gradient method, Agri. Forest Meteorol., 135, 44–60, 2005b.

Griffis, T. J., Zhang, J., Baker, J. M., Kljun, N., and Billmark, K.: Determining carbon isotope signatures from micrometeorological measurements: implications for studying biosphere-atmosphere exchange processes, Bound.-Lay. Meteorol., 123, 295–316, 2007.

Griffis, T. J., Sargent, S. D., Baker, J. M., Lee, X., Tanner, B. D., Greene, J., Swiatek, E., and Billmark, K.: Direct measurement of biosphere-atmosphere isotopic CO2 exchange using the eddy covariance technique, J. Geophys. Res.-Atmos., 113, D08304, http://dx.doi.org/10.1029/2007JD009297doi:10.1029/2007JD009297, 2008.

Griffis, T. J., Sargent, S. D., Lee, X., Baker, J. M., Greene, J., Erickson, M., Zhang, X., Billmark, K., Schultz, N., Xiao, W., and Hu, N.: Determining the oxygen isotope composition of evapotranspiration using eddy covariance, Bound.-Lay. Meteorol., 137, 307–326, 2010.

Haverd, V., Leuning, R., Griffith, D., Van Gorsel, E., and Cuntz, M.: The turbulent Lagrangian time scale in forest canopies constrained by fluxes, concentrations and source distributions, Bound.-Lay. Meteorol., 130, 209–228, 2009.

Kammer, A., Tuzson, B., Emmenegger, L., Knohl, A., Mohn, J., and Hagedorn, F.: Application of a quantum cascade laser-based spectrometer in a closed chamber system for real-time $\delta ^13$C and $\delta ^18$O measurements of soil-respired CO2, Agr. Forest Meteorol., 151, 39–48, 2011.

Keeling, C. D.: The concentration and isotopic abundances of atmospheric carbon dioxide in rural areas, Geochim. Cosmochim. Ac., 13, 322–334, 1958.

Law, B. E., Ryan, M. G., and Anthoni, P. M.: Seasonal and annual respiration of a Ponderosa Pine ecosystem, Glob. Change Biol., 5, 169–182, 1999.

Lee, X. H., Fuentes, J. D., Staebler, R. M.,and Neumann, H. H.: Long-term observation of the atmospheric exchange of CO2 with a temperate deciduous forest in Southern Ontario, Canada, J. Geophys. Res.-Atmos., 104, 15975–15984, 1999.

Lee, X. H., Sargent, S., Smith, R., and Tanner, B.: In situ measurement of the water vapor $^18$O/$^16$O isotope ratio for atmospheric and ecological applications, J. Atmos. Ocean. Tech., 22, 555–565, 2005.

Leuning, R.: Estimation of scalar source/sink distributions in plant canopies using Lagrangian dispersion analysis: corrections for atmospheric stability and comparison with a multilayer canopy model, Bound.-Lay. Meteorol., 96, 293–314, 2000.

Leuning, R., Denmead, O. T., Miyata, A., and Kim, J.: Source/sink distributions of heat, water vapour, carbon dioxide and methane in a rice canopy estimated using Lagrangian dispersion analysis, Agr. Forest Meteorol., 104, 233–249, 2000.

Miller, J. B., Yakir, D., White, J. W. C., and Tans, P. P.: Measurement of $^18$O/$^16$O in the soil-atmosphere CO2 flux, Global Biogeochem. Cy., 13, 761–774, 1999.

Moldrup, P., Olesen, T., Komatsu, T., Yoshikawa, S., Schjonning, P., and Rolston, D. E.: Modeling diffusion and reaction in soils: X. A unifying model for solute and gas diffusivity in unsaturated soil, Soil Sci., 168, 321–337, 2003.

Neumann, H. H. and den Hartog, G.: Leaf-area measurements based on hemispheric photographs and leaf-litter collection in a deciduous forest during autumn leaf-fall, Agr. Forest Meteorol., 45, 325–345, 1989.

Ogée, J., Peylin, P., Cuntz, M., Bariac, T., Brunet, Y., Berbigier, P., Richard, P., and Ciais, P.: Partitioning net ecosystem carbon exchange into net assimilation and respiration with canopy-scale isotopic measurements: an error propagation analysis with $^13$CO2 and CO$^18$O data, Global Biogeochem. Cy., 18, GB2019, http://dx.doi.org/10.1029/2003GB002166doi:10.1029/2003GB002166, 2004.

Ohkubo, S., Kosugi, Y., Takanashi, S., Mitani, T., and Tani, M.: Comparison of the eddy covariance and automated closed chamber methods for evaluating nocturnal CO2 exchange in a Japanese Cypress forest, Agr. Forest Meteorol., 142, 50–65, 2007.

Pataki, D. E., Ehleringer, J. R., Flanagan, L. B., Yakir, D., Bowling, D. R., Still, C. J., Buchmann, N., Kaplan, J. O., and Berry, J. A.: The application and interpretation of Keeling plots in terrestrial carbon cycle research, Global Biogeochem. Cy., 17, 1022, http://dx.doi.org/10.1029/2001GB001850doi:10.1029/2001GB001850, 2003.

Qiu, G. and Warland, J. S.: Inferring profiles of energy fluxes within a soybean canopy using Lagrangian analysis, Agr. Forest Meteorol., 139, 119–137, 2006.

Raupach, M. R.: A Lagrangian analysis of scalar transfer in vegetation canopies, Q. J. Roy. Meteorol. Soc., 113, 107–120, 1987.

Raupach, M. R.: A practical Lagrangian method for relating scalar concentrations to source distributions in vegetation canopies, Q. J. Roy. Meteorol. Soc., 115, 609–632, 1989a.

Raupach, M. R.: Applying Lagrangian fluid-mechanics to infer scalar source distributions from concentration profiles in plant canopies, Agr. Forest Meteorol., 47, 85–108, 1989b.

Riley, W. J.: A modeling study of the impact of the $\delta ^18$O value of near-surface soil water on the delta $^18$O value of the soil-surface CO2 flux, Geochim. Cosmochim. Ac., 69, 1939–1946, 2005.

Riley, W. J., Still, C. J., Helliker, B. R., Ribas-Carbo, M., and Berry, J. A.: $^18$O composition of CO2 and H2O ecosystem pools and fluxes in a tallgrass prairie: simulations and comparisons to measurements, Glob. Change Biol., 9, 1567–1581, 2003.

Rochette, P., Flanagan, L. B., and Gregorich, E. G.: Separating soil respiration into plant and soil components using analyses of the natural abundance of carbon-13, Soil Sci. Soc. Am. J., 63, 1207–1213, 1999.

Santos, E. A., Wagner-Riddle, C., Warland, J. S., and Brown, S.: Applying a lagrangian dispersion analysis to infer carbon dioxide and latent heat fluxes in a corn canopy, Agr. Forest Meteorol., 151, 620–632, 2011.

Saxton, K. E. and Willey, P. H.: The SPAW model for agricultural field and pond hydrologic simulation, in: Watershed models, edited by: Frevert, D. K. and Singh, V. P., 2006.

Seibt, U., Wingate, L., Lloyd, J., and Berry, J. A.: Diurnally variable $\delta ^18$O signatures of soil CO2 fluxes indicate carbonic anhydrase activity in a forest soil, J. Geophys. Res.-Biogeo., 111, G04005, http://dx.doi.org/10.1029/2006JG000177doi:10.1029/2006JG000177, 2006.

Skirrow, G.: The dissolved gases: carbon dioxide, in: Chemical Oceanography, edited by: Riley, J. P. and Skirrow, G., Academic Press, San Diego, CA, 1975.

Styles, J. M., Raupach, M. R., Farquhar, G. D., Kolle, O., Lawton, K. A., Brand, W. A., Werner, R. A., Jordan, A., Schulze, E. D., Shibistova, O., and Lloyd, J.: Soil and canopy CO2, $^13$CO2, H2O and sensible heat flux partitions in a forest canopy inferred from concentration measurements, Tellus B, 54, 655–676, 2002.

Tans, P. P.: Oxygen isotopic equilibrium between carbon dioxide and water in soils, Tellus B, 50, 163–178, 1998.

Tans, P. P., Berry, J. A., and Keeling, R. F.: Oceanic C-13/C-12 Observations – a New Window on Ocean Co2 Uptake, Global Biogeochem. Cy., 7, 353–368, 1993.

Taylor, G.: Diffusion by continuous movements, Proceedings London Mathematical Society, 20, 196–211, 1921.

Teklemariam, T., Staebler, R. M., and Barr, A. G.: Eight years of carbon dioxide exchange above a mixed forest at Borden, Ontario, Agr. Forest Meteorol., 149, 2040–2053, 2009.

Tuzson, B., Mohn, J., Zeeman, M. J., Werner, R. A., Eugster, W., Zahniser, M. S., Nelson, D. D., Mcmanus, J. B., and Emmenegger, L.: High precision and continuous field measurements of $\delta ^13$C and $\delta ^18$O in carbon dioxide with a cryogen-free QCLAS, Appl. Phys. B-Lasers O., 92, 451–458, 2008.

Wagner-Riddle, C., Thurtell, G. W., and Edwards, G. C.: Trace gas concentration measurements for micrometeorological flux quantification, in: Micrometerology in agricultural systems. Agronomy Monography, edited by: Hatfield, J. L., and Baker, J. M., AASA, CSSA, SSSA, Madson, WI, USA., 2005.

Warland, J. S. and Thurtell, G. W.: A Lagrangian solution to the relationship between a distributed source and concentration profile, Bound.-Lay. Meteorol., 96, 453–471, 2000.

Weiss, R. F.: Carbon dioxide in water and seawater: the solubility of a non-ideal gas, Mar. Chem., 2, 203–215, 1974.

Welp, L. R., Lee, X., Kim, K., Griffis, T. J., Billmark, K. A., and Baker, J. M.: $\delta ^18$O of water vapour, evapotranspiration and the sites of leaf water evaporation in a soybean canopy, Plant Cell Environ., 31, 1214–1228, 2008.

Wilson, J. D.: Turbulent transport within the plant canopy, in: Estimation of areal evapotranspiration, edited by: Black, T. A., Spittlehouse, D. L., Novak, M. D., and Price, D. T., IAHS Publication 177, Wallingford, U.K., 1989.

Wingate, L., Seibt, U., Maseyk, K., Ogee, J., Almeida, P., Yakir, D., Pereira, J. S., and Mencuccini, M.: Evaporation and carbonic anhydrase activity recorded in oxygen isotope signatures of net CO2 fluxes from a Mediterranean soil, Glob. Change Biol., 14, 2178–2193, 2008.

Wingate, L., Ogee, J., Cuntz, M., Genty, B., Reiter, I., Seibt, U., Yakir, D., Maseyk, K., Pendall, E. G., Barbour, M. M., Mortazavi, B., Burlett, R., Peylin, P., Miller, J., Mencuccini, M., Shim, J. H., Hunt, J., and Grace, J.: The impact of soil microorganisms on the global budget of $\delta ^18$O in atmospheric CO2, P. Natl. Acad. Sci. USA, 106, 22411–22415, 2009.

Wingate, L., Ogee, J., Burlett, R., and Bosc, A.: Strong seasonal disequilibrium measured between the oxygen isotope signals of leaf and soil CO2 exchange, Glob. Change Biol., 16, 3048–3064, 2010.

Wu, A., Black, A., Verseghy, D. L., and Bailey, W. G.: Comparison of Two-Layer and Single-Layer Canopy Models With Lagrangian and K-Theory Approaches in Modelling Evaporation From Forests, Int. J. Climatol., 21, 1821–1839, 2001.

Xiao, W., Lee, X., Griffis, T. J., Kim, K., Welp, L. R., and Yu, Q.: A modeling investigation of canopy-air oxygen isotopic exchange of water vapor and carbon dioxide in a soybean field, J. Geophys. Res.-Biogeo., 115, G01004, http://dx.doi.org/10.1029/2009JG001163doi:10.1029/2009JG001163, 2010.

Yakir, D. and Sternberg, L. D. L.: The use of stable isotopes to study ecosystem gas exchange, Oecologia, 123, 297–311, 2000.

Yakir, D. and Wang, X. F.: Fluxes of CO2 and water between terrestrial vegetation and the atmosphere estimated from isotope measurements, Nature, 380, 515–517, 1996.

Zhang, J., Griffis, T. J., and Baker, J. M.: Using continuous stable isotope measurements to partition net ecosystem CO2 exchange, Plant Cell Environ., 29, 483–496, 2006.

Zobitz, J. M., Keener, J. P., Schnyder, H., and Bowling, D. R.: Sensitivity analysis and quantification of uncertainty for isotopic mixing relationships in carbon cycle research, Agr. Forest Meteorol., 136, 56–75, 2006.