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\section{Introduction}  Although progress towards defining and characterizing element and energy flow through above-ground food webs and detritivore food webs has been made, made CITATIONS,  we have only a rudimentary understanding of how matter and energy flows through soil microbial communities. This deficiency is driven by the staggering complexity of soil microbial food webs and the opacity of these biological systems to current methods for describing soil microorganism activities. Relating community composition to ecosystem function for certain microbial processes in soils, such as nitrification and denitrification, which are mediated by defined functional groups has been a useful approach. Carbon-cycling processes, however, have proven more recalcitrant to study due to the wide range of organisms participating in these reactions.   There Excluding plant biomass, there  are 2,300 Pg of carbon (C) stored in soils worldwide, excluding plant biomass, worldwide  which accounts for $\sim$80\% of the global terrestrial C pool \cite{Amundson_2001,Mendelsohn_2001,IPCC2007Synth,elsen_Ayres_Wall_Bardgett_2011,Lal_2008,BATJES_1996,Lal_2008}. When organic C from plants reaches soil it is degraded through the activity of fungi by fungi, archaea  and bacteria. This C may be is  rapidly returned to the atmosphere as CO\textsubscript{2} or may remain remains  in the soil as humic substances that may can  persist up to 2000 years \cite{yanagita1990natural}. The majority of plant biomass  C is respired and on respired. On  an annual basis soil respiration produces 10 times more CO\textsubscript{2} than anthropogenic emissions \cite{chapin2002principles}. Global changes in atmospheric CO\textsubscript{2}, temperature, and ecosystem nitrogen inputs, are expected to impact primary production and C inputs to soils \citep{Groenigen_2006}, \citep{Groenigen_2006}  but it remains difficult to predict the response of soil processes to anthropogenic change \cite{DAVIDSON_2006}. Current climate change models concur on atmospheric and ocean C predictions but not terrestrial \cite{Friedlingstein_2006}. The disagreeable predictive power between models for Contrasting  terrestrial ecosystems reflects ecosystem model predictions reflect  how little we know is known  about belowground soil  C cycling dynamics. It is estimated that 80-90\% of the C cycling in soil is mediated by microorganisms \cite{ColemanCrossley_1996,Nannipieri_2003}. Understanding microbial processing of nutrients in soils presents a special challenge due to the hetergeneous nature of soil ecosystems and our limitations in methodologies. Soils consist of an overwhelming biological, chemical, and physical complexity which affects microbial community composition, diversity, and structure (refs). Confounding factors such as physical protection/aggregation, moisture content, pH, temperature, frequency and type of land disturbance, soil history, mineralogy, N quality and availability, and litter quality have all been shown to affect the ability of the soil microbial community to access and metabolize C substrates \cite{Schlesinger_1977,dgett_Wall_Hattenschwiler_2010,Sollins_Homann_Caldwell_1996,Torn_Vitousek_Trumbore_2005,TRUMBORE_2006,Schimel_2012}. Furthermore, rates of metabolism are often measured without knowing the identity of the microbial species specifically involved \cite{ndi_Pietramellara_Renella_2003} resulting in uncertainty in importance of community diversity in maintaining ecosystem functioning \cite{Allison_2008,ndi_Pietramellara_Renella_2003,Schimel_2012}. Litter bag experiments have shown that the community composition of soils can have quantitative and qualitative impacts on the breakdown of plant materials \cite{Schimel_1995}, and reciprocal exchange of litter type and microbial inocula under controlled environmental conditions reveals that differences in community composition can account for 85\% of the variation in litter carbon mineralization \cite{Strickland_2009}. In addition, simple assembled communities of cellulose degraders reveal that the composition of the community has significant impacts on the rate of cellulose degradation \cite{Wohl_2004}.