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Differences in the degradation of labile C sources (ie. glucose, xylose, or sucrose) and complex C polymers (ie. cellulose or lignin) have been detected (Engelking et al 2007, Anderson and Domsch 1973, Stotzky and Norman 1961, Alden et al 2001, Nannipieri et al 2003). Nearly complete degradation of sucrose within five days has been observed, while degradation of cellulose takes between 15-25 days (Engelking et al 2007). Respiration from glucose-treated soils showed an initial increase in respiration at 2-6 hours followed by a second increase between 6-10 hours (Anderson and Domsch 1973, Stotzky and Norman 1961, Alden et al 2001, Nannipieri et al 2003).    Goldfarb then functional guild literature (fierer) then propose that phyla do not serve as a single functional unit as many clades within a phyla may respond differently.   \cite{Fierer_2012} - demonstrates that taxonomic and phylogenetic diversity does not confer functional diversity.  The aim of this study is to track the path of C added to soil as a complex C mixture to provide insight into these dynamic systems. A previous study has shown that 13C labeled plant residues enable tracking of C through microbial pathways (Evershed et al 2006). Utilizing this technique with single 13C labeled substrates added as a complex C mixture will allow us to test how different C containing components cascade through discrete taxa within the soil microbial community. Powerful techniques such as nucleic acid stable isotope probing (SIP) coupled with 454 pyrosequencing can then be used to parse out and identify these 13C labeled portions of the microbial community to reveal the community members that are responsible for the transformation of the labeled C. Coupling complex C additions additions to microcosm incubations with nucleic acid stable isotope probing (SIP) provides a means of looking into microbial community functions while minimizing other factors affecting the fate of C. This allows us to sift out the specific organisms or functional guilds that are responsible for the cycling of that specific C substrate.