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Degradative succession refers to the temporal changes in species or functional guilds that occurs during the sequential degradation of constituents of a nutrient resource \cite{townsend2003essentials,Bastian_2009}. The decomposition of a nutrient source is hypothesized to promote succession of active community members as compounds are sequentially degraded \cite{Biddanda_1988}. Differences in the degradation of labile C sources (ie. glucose, xylose, or sucrose) and complex C polymers (ie. cellulose or lignin) have been detected \cite{Engelking_2007,Anderson_1973,Stotzky_1961,Alden_2001,Furukawa_1996,Fontaine_2003,Blagodatskaya_2007,Jenkins_2010,Rui_2009,Fierer_2010}. A classic example of plant litter degradative succession is characterized by a series of stages in which sugar fungi dominate in stage one, followed by cellulolytic fungi in stage two, and lignin degrading fungi in the final stage \cite{Gessner_2010}. This demonstrates not only the succession of detritivores but also the sequential degradation of litter constituents starting with consumption of the most labile C sources followed by degradation of more complex and polymeric C sources. These studies suggest that if a complex mixture of labile and polymeric C were added to soil two waves of degradation could be observed; labile C degradation early on and subsequent polymeric C degradation. We propose this temporal cascade from labile C degraders preceeding the polymeric C degraders occurs in natural microbial communities, called herein 'microbial community succession'. It is important to understand these decomposition sequences because as environments are altered it results in measurable and functional changes in soil C \cite{Grandy_2008} which could cumulatively have large impacts at a global scale.   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 ^{13}C \textsuperscript{13}C  labeled plant residues enable tracking of C through microbial pathways \cite{Evershed_2006}. Utilizing this technique with single ^{13}C labeled substrates added as a complex C mixture allows us to test how different C substrates cascade through discrete taxa within the soil microbial community. Powerful techniques such as nucleic acid stable isotope probing coupled with next generation sequencing (SIP-NGS) can then be used to parse out and identify these ^{13}C labeled portions of the microbial community to reveal the community members that are responsible for the transformation of the labeled C. Using these methods in compilation with microcosm incubations provides a means of looking into microbial community functions while minimizing other environmental factors affecting the fate of C. Ultimately we identify discrete organisms or functional guilds that are responsible for the cycling of specific C substrates.