Soil contains approximately 75% of the carbon pool on land - three times more than the
amount stored in living plants and animals (Schlesinger 1999). Therefore, soils play a
major role in maintaining a balanced global carbon cycle. Models of the soil carbon
ecosystem assume a strong relationship between organic matter (litter) inputs and soil
carbon accumulation, but there is little evidence for this assumption. To test the
relationship between stored soil carbon and organic matter alterations, we used the DIRT
(Detrital Input and Removal Treatment) Network on 27 plots of soil. The DIRT Network
assesses how rates and sources of plant litter inputs influence accumulations or losses of
organic matter in forest soils. The soil plots are located at the University of Michigan
Biological Station (UMBS). Each plot had two depths, the first being a 0-10cm profile and
the other a 10-20cm profile. The results showed that the 0-10cm depth trial had
significant increases from the woody debris addition and significant decreases in the
no-input exclusion. The 10-20cm depth trial showed no significant results across all
trials. We concluded that the increase in stored soil carbon from applied woody debris
was more likely because the woody debris takes longer to decompose rather than that
the decomposition yielded more stored carbon. Too, we discussed that the lack of organic
matter content from the no-input trial is representative of the decreased decomposition
rate and lack of microbial interest.