Effects of Detrital Inputs and Roots on Carbon Saturation Deficit of a Temperate Forest Soil

SuMMARY This study of long-term changes in SOM inputs to tem-perate deciduous forest soils showed that deciduous leaf litter plays a primary role in affecting soil C accumulation. Soil frac-tions were found to be functionally disparate; decomposition of coarse roots tended to increase cPOM-C accumulation, while cessation of deciduous litter inputs decreased C accumulation in microaggregates within large macroaggregates. The latter re-inforces the use of microaggregates within large macroaggregates as a diagnostic fraction for changes in soil C content in forest soils. Furthermore, increasing trends of C content with increas-ing SOM inputs suggest that this soil maintains a substantial sat -uration deficit, implying that even relatively high-C forest soils maintain the potential for C sequestration. ACKNowledgMeNTS We wish to thank Elizabeth Carrington for her valuable contributions to this research. ReFeReNCeS Angers, D.A. , M.A. Bolinder, M.R. Carter, E.G. Gregorich, C.F. Drury, B.C. 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