See more from this Session: General Forest, Range and Wildland Soils: II
Radiocarbon-enriched leaf and root litter and humus have been deployed under at the University of Michigan Biological Station (MI-UMBS), Bartlett Forest (NH-BF), Harvard Forest (MA-HF), and Baskett Research and Education Area in the Missouri Ozarks (MO-OZ). In addition to investigating rates of C transfer from litter to bulk O horizon sand mineral soil, we used density fractionation to separate bulk mineral soil into three pools of varying stability. These fractions are being used to identify which soil organic matter pools incorporate C from the experimental sources and determine pool-specific transfer rates. We will present results from the first two years of enriched-leaf and -humus applications and first year of enriched-root decomposition experiments. Preliminary results show that little humus-C was incorporated into soil over 2 years, but that by the second year after enriched-litter applications began new litter C had been transferred to mineral soil at MO-OZ and MI-UMBS.