Comparative analysis of reference materials
History
There are several methods with which to determine black carbon in soils and sediments, but results among methods are not comparable. Development of common reference materials resolves only some of the BC methodological uncertainties. A comparative analysis project using these reference materials started in January 2004 to gauge how different methods can be used to interpret BC components in aerosol, soils and sediments. The intention of the study was not to advocate a single technique; rather, such a comparative analysis will help immensely to better understand what is actually being determined by the different methods and how these results relate to one another. A set of reference materials were chosen to achieve this aim (first announced here (PDF, 56 Kb)). We actively solicited researchers of all disciplines for this intercomparison. We tried to connect researchers who measure BC in the atmosphere with those who measure it in soils and sediments. Distribution of samples was completed by February 2004. Participating research groups made available all results and details of their methodology for eventual group publication. The first results were presented during the 2005 European Geoscience Union meeting (April 2005), where we had a Symposium on the Analysis and Characterization of Black Carbon in the Environment (BG1.08).
Results
The results of the ring trial have been published in Global Biogeochemical Cycles in May 2007:
Hammes, K., Schmidt, M.W.I., Smernik, R.J., Currie, L.A.R., Ball, W.P., Nguyen, T.H., Louchouarn, P., Houel, S., Gustafsson, Ö., Elmquist, M., Cornelissen, G., Skjemstad, J.O., Masiello, C.A., Song, J., Peng, P., Mitra, S., Dunn, J.C., Hatcher, P.G., Hockaday, W.C., Smith, D.M., Hartkopf-Fröder, C., Böhmer, A., Lüer, B., Huebert, B.J., Amelung, W., Brodowski, S., Huang, L., Zhang, W., Gschwend, P.M., Flores-Cervantes, D.X., Largeau, C., Rouzaud, J.-N., Rumpel, C., Guggenberger, G., Kaiser, K., Rodionov, A., Gonzalez-Vila, F.J., Gonzalez-Perez, J.A., de la Rosa, J.M., Manning, D.A.C., López-Capél, E., Ding, L. Comparison of black carbon quantification methods using reference materials from soil, water, sediment and the atmosphere, and implications for the global carbon cycle. Global Biogeochemical Cycles, 21, GB3016, doi:10.1029/2006GB002914.
A short report on the symposium held on black carbon research in soil, sediment and the atmosphere at the European Geoscience Union meeting in Vienna (18-19 April 2007), as well as summary of the comparative study conclusions, can be found here (PDF, 61 Kb).