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Methods of Separating Soil Carbon Pools Affect the Chemistry and Turnover Time of Isolated Fractions

Published online by Cambridge University Press:  18 July 2016

Cristina Castanha ,
Susan Trumbore  and
Ronald Amundson
Cristina Castanha*
Affiliation:
Lawrence Berkeley National Lab, 1 Cyclotron Road, Mail Stop 70A-4418, Berkeley, California 94720, USA
Susan Trumbore
Affiliation:
Physical Sciences Research Facility, University of California, Irvine, California 92697-3100, USA
Ronald Amundson
Affiliation:
Ecosystem Sciences, 137 Mulford Hall, University of California, Berkeley, California 94720–3114, USA
*
Corresponding author. Email: [email protected]
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Abstract

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A variety of physical and chemical techniques are used to fractionate soil organic matter, but detailed comparisons of the different approaches and tests of how separation methods influence the properties of isolated organic matter pools are lacking. In this case study based on A horizon samples of 2 California coniferous forests soils, we 1) evaluate the effects of root removal and ultrasonic dispersion on the properties of the <2 g cm-3 light fraction and 2) compare the properties of fractions obtained by sequential density separations of ultrasonically treated soil with those obtained by density followed by acid/base hydrolysis (Trumbore et al. 1996).

A root-removal effort based on hand-picking visible roots reduced the radiocarbon content and increased the estimated turnover time of the light fraction by roughly 12%. Root-removal protocols that vary between investigators thus can potentially confound variability in carbon cycling for this fraction caused by environmental factors, such as climate. Ultrasonic dispersion did not have a clear effect on the light fraction C and N content or isotopic signature, but led to a decrease in the % C and C/N of the recovered heavy fractions, and losses of 12–19% of the total soil C to the sodium metatungstate density solution.

Sequentially isolated density fractions clearly differed in mineralogy and organic matter chemistry, but natural-abundance 14C analyses indicated that distinct mineral phases did not correspond to unique C-turnover pools. Density fractions containing kaolinite group minerals alone and in combination with hydroxy-interlayered vermiculite were found to harbor both fast and slow cycling carbon. In contrast, severe chemical treatment isolated a carbon pool with the lowest overall 14C content and longest inferred mean turnover time. Overall, our results show that care must be taken when relying on physical (density) separation to isolate soil fractions with different dynamics, as the details of treatment will influence the results.

Type
Articles
Information
Radiocarbon , Volume 50 , Issue 1 , 2008 , pp. 83 - 97
Copyright
Copyright © 2008 by the Arizona Board of Regents on behalf of the University of Arizona 

References

Amundson, R, Stern, L, Baisden, T, Wang, Y. 1998. The isotopic composition of soil and soil-respired CO2 . Geoderma 82(1–3):83–114.Google Scholar
Baisden, WT, Amundson, R, Cook, AC, Brenner, DL. 2002. Turnover and storage of C and N in five density fractions from California annual grassland surface soils. Global Biogeochemical Cycles 16(4):1117, doi:10.1029/2001GB001822.CrossRefGoogle Scholar
Balesdent, J. 1987. The turnover of soil organic fractions estimated by radiocarbon dating. The Science of the Total Environment 62:405–8.CrossRefGoogle Scholar
Basile-Doelsch, I, Amundson, R, Stone, WEE, Borschneck, D, Bottero, JY, Moustier, S, Masin, F, Colin, F. 2007. Mineral control of carbon pools in a volcanic soil horizon. Geoderma 137(3–4):477–89.Google Scholar
Boutton, TW. 1991. Stable carbon isotope ratios of natural materials: I. Sample preparation and mass spectrometric analysis. In: Coleman, DC, Fry, B, editors. Carbon Isotope Techniques. New York: Academic Press. p 155–71.Google Scholar
Brindley, GW, Brown, G, editors. 1984. Crystal Structures of Clay Minerals and Their X-ray Diffraction Identification. London: Mineralogical Society. 495 p.Google Scholar
Christensen, BT. 1992. Physical fractionation of soil and organic matter in primary particle size and density separates. Advances in Soil Science 20:1–90.Google Scholar
Crow, SE, Swanston, CW, Lajtha, K, Brooks, JR, Keirstead, H. 2007. Density fractionation of forest soils: methodological questions and interpretation of incubation results and turnover time in an ecosystem context. Biogeochemistry 85(1):69–90.CrossRefGoogle Scholar
Dahlgren, RA, Boettinger, JL, Huntington, GL, Amundson, RG. 1997. Soil development along an elevational transect in the western Sierra Nevada, California. Geoderma 78(3–4):207–36.CrossRefGoogle Scholar
Douglas, LA. 1989. Vermiculites. In: Dixon, JB, Weed, SB, editors. Minerals in Soil Environments. Madison: Soil Science Society of America. p 635–68.Google Scholar
Ewing, SA, Sanderman, J, Baisden, WT, Wang, Y, Amundson, R. 2006. Role of large-scale soil structure in organic carbon turnover: evidence from California grassland soils. Journal of Geophysical Research 111: G03012, doi:10.1029/2006JG000174.Google Scholar
Gaudinski, JB, Trumbore, SE, Davidson, EA, Zheng, S. 2000. Soil carbon cycling in a temperate forest: radiocarbon-based estimates of residence times, sequestration rates and partitioning of fluxes. Bio geochemistry 51(1):33–69.Google Scholar
Gaudinski, JB, Trumbore, S, Davidson, E, Cook, A, Markewitz, D, Richter, D. 2001. The age of fine-root carbon in three forests of the eastern United States measured by radiocarbon. Oecologia 129(3):420–9.Google Scholar
Goh, KM, Stout, JD, O'Brien, BJ. 1984. The significance of fractionation in dating the age and turnover of soil organic matter. New Zealand Journal of Science 27(1):69–72.Google Scholar
Golchin, A, Oades, JM, Skjemstad, JO, Clarke, P. 1994. Study of free and occluded particulate organic matter in soils by solid state 13C CP/MAS NMR spectroscopy and scanning electron microscopy. Australian Journal of Soil Research 32(2):285–309.Google Scholar
Golchin, A, Baldock, JA, Clarke, P, Higashi, T, Oades, JM. 1997. The effects of vegetation and burning on the chemical composition of soil organic matter of a volcanic ash soil as shown by 13C NMR spectroscopy. II. Density fractions. Geoderma 76(3–4):175–92.Google Scholar
Greenland, DJ, Ford, GW. 1964. Separation of partially humified organic materials from soils by ultrasonic dispersion. In: 8th International Congress of Soil Science Transactions. Bucharest, Romania. p 137–48.Google Scholar
Jastrow, JD. 2003. Mean residence time of soil carbon pools: controlling factors and implications for soil carbon cycling. Ecological Society of America Annual Meeting Abstracts 88:166–7.Google Scholar
Jenkinson, DS, Andrew, SPS, Lynch, JM, Goss, MJ, Tinker, PB. 1990. The turnover of organic carbon and nitrogen in soil. Philosophical Transactions of the Royal Society B Biological Sciences 329(1255):361–8.Google Scholar
Kleber, M, Sollins, P, Sutton, R. 2007. A conceptual model of organo-mineral interactions in soils: self-assembly of organic molecular fragments into zonal structures on mineral surfaces. Bio geochemistry 85(1):9–24.Google Scholar
Krull, ES, Swanston, CW, Skjemstad, JO, McGowan, JA. 2006. Importance of charcoal in determining the age and chemistry of organic carbon in surface soils. Journal of Geophysical Research 111: G04001, doi:10.1029/2006JG000194.CrossRefGoogle Scholar
Levin, I, Hesshaimer, V. 2000. Radiocarbon—a unique tracer of the global carbon cycle dynamics. Radiocarbon 42(1):69–80.Google Scholar
Masiello, CA, Chadwick, OA, Southon, J, Torn, MS, Harden, JW. 2004. Weathering controls on mechanisms of carbon storage in grassland soils. Global Biogeochemical Cycles 18: GB4023, doi:10.1029/2004GB002219.Google Scholar
Minagawa, M, Winter, DA, Kaplan, IR. 1984. Comparison of Kjeldahl and combustion methods for measurement of nitrogen isotope ratios in organic matter. Analytical Chemistry 56(11):1859–61.Google Scholar
Monnier, G, Turc, L, Jeanson-Luusinang, C. 1962. Une methode de fractionnement densimetrique par centrifugation des mateires organiques du sol. Annales Agronomiques 13(1):55–63. In French.Google Scholar
Nelson, DW, Sommers, LE. 1996. Carbon and organic matter. In: Sparks, DL, editor. Methods of Soil Analysis. Part 3: Chemical Methods. Soil Science Society of America, Book Series 5. Madison: Soil Science Society of America. p 961–1010.Google Scholar
Oades, JM. 1995. An overview of processes affecting the cycling of organic carbon in soils. In: Zepp, RG, Sonntag, C, editors. The Role of Nonliving Organic Matter in the Earth's Carbon Cycle. New York: John Wiley and Sons Ltd. p 293–303.Google Scholar
O'Brien, BJ, Stout, JD. 1978. Movement and turnover of soil organic matter as indicated by carbon isotope measurements. Soil Biology and Biochemistry 10(4):309–17.Google Scholar
Oik, DC, Gregorich, EG. 2006. Overview of the Symposium Proceedings, “Meaningful Pools in Determining Soil Carbon and Nitrogen Dynamics.” Soil Science Society of America Journal 70(3):967–74.Google Scholar
Parton, WJ, Schimel, DS, Cole, CV, Ojima, DS. 1987. Analysis of factors controlling soil organic matter levels in Great Plains grasslands. Soil Science Society of America Journal 51(5):1173–9.Google Scholar
Paul, EA, Collins, HP, Leavitt, SW. 2001. Dynamics of resistant soil carbon of Midwestern agricultural soils measured by naturally occurring 14C abundance. Geoderma 104(3–4):239–56.Google Scholar
Paul, EA, Morris, SJ, Conant, RT, Plante, AF. 2006. Does the acid hydrolysis-incubation method measure meaningful soil organic carbon pools? Soil Science Society of America Journal 70(3):1023–35.CrossRefGoogle Scholar
Rasmussen, C, Torn, MS, Southard, RJ. 2005. Mineral assemblage and aggregates control carbon dynamics in a California conifer forest. Soil Science Society of America Journal 69(6):1711–21.Google Scholar
Rodhe, H. 1992. Modeling biogeochemical cycles. In: Butcher, SS, Charlson, RJ, Orians, GH, Wolfe, GV, editors. Global Biogeochemical Cycles. San Diego: Academic Press. p 55–72.Google Scholar
Schoeneberger, PJ, Wysocki, DA, Benham, EC, Broderson, WD. 1998. Field Book for Describing and Sampling Soils. Natural Resources Conservation Service, USDA. Lincoln: National Soil Survey Center.Google Scholar
Shang, C, Tiessen, H. 1998. Organic matter stabilization in two semiarid tropical soils: size, density, and magnetic separations. Soil Science Society of America Journal 62(5):1247–57.Google Scholar
Shang, C, Tiessen, H. 2001. Sequential versus parallel density fractionation of silt-sized organomineral complexes of tropical soils using metatungstate. Soil Biology and Biochemistry 33(2):259–62.CrossRefGoogle Scholar
Six, J, Merckx, R, Kimpe, K, Paustian, K, Elliott, ET. 2000. A re-evaluation of the enriched labile soil organic matter fraction. European Journal of Soil Science 51(2):283–93.CrossRefGoogle Scholar
Six, J, Guggenberger, G, Paustian, K, Haumaier, L, Elliott, ET, Zech, W. 2001. Sources and composition of soil organic matter fractions between and within soil aggregates. European Journal of Soil Science 52(4):607–18.Google Scholar
Sollins, P, Spycher, G, Topik, C. 1983. Processes of soil organic matter accretion at a mud flow chronosequence Mt. Shasta, California. Ecology 64(5):1273–82.Google Scholar
Sollins, P, Swanston, C, Kleber, M, Filley, T, Kramer, M, Crow, S, Caldwell, BA, Lajtha, K, Bowden, R. 2006. Organic C and N stabilization in a forest soil: evidence from sequential density fractionation. Soil Biology and Biochemistry 38(11):3313–24.Google Scholar
Sposito, G. 1989. The Chemistry of Soils. New York: Oxford University Press. 304 p.Google Scholar
Stuiver, M, Polach, HA. 1977. Discussion: reporting of 14C data. Radiocarbon 19(3):355–63.Google Scholar
Swanston, CW, Torn, MS, Hanson, PJ, Southon, JR, Garten, CT, Hanlon, EM, Ganio, L. 2005. Initial characterization of processes of soil carbon stabilization using forest stand-level radiocarbon enrichment. Geoderma 128(1–2):52–62.CrossRefGoogle Scholar
Swift, RS. 1996. Organic matter characterization. In: Sparks, DL, editor. Methods of Soil Analysis. Part 3: Chemical Methods. Soil Science Society of America, Book Series 5. Madison: Soil Science Society of America. p 1011–69.Google Scholar
Torn, MS, Lapenis, AG, Timofeev, A, Fischer, ML, Babikov, BV, Harden, JW. 2002. Organic carbon and carbon isotopes in modern and 100-year-old-soil archives of the Russian steppe. Global Change Biology 8(10):941–53.Google Scholar
Trumbore, SE. 1988. Carbon cycling and gas exchange in soils [PhD dissertation]. New York: Columbia University. 194 p.Google Scholar
Trumbore, SE. 2000. Age of soil organic matter and soil respiration: radiocarbon constraints on belowground C dynamics. Ecological Applications 10(2):399–411.Google Scholar
Trumbore, SE, Zheng, S. 1996. Comparison of fractionation methods for soil organic matter 14C analysis. Radiocarbon 38(2):219–29.Google Scholar
Trumbore, SE, Vogel, JS, Southon, JR. 1989. AMS 14C measurements of fractionated soil organic matter: an approach to deciphering the soil carbon cycle. Radiocarbon 31(3):644–54.Google Scholar
Trumbore, SE, Chadwick, OA, Amundson, R. 1996. Rapid exchange between soil carbon and atmospheric carbon dioxide driven by temperature change. Science 272(5260):393–6.Google Scholar
Wang, Y, Hsieh, Y-P. 2002. Uncertainties and novel prospects in the study of the soil carbon dynamics. Chemosphere 49(8):791–804.Google Scholar