Date of Award

Winter 2011

Project Type


Program or Major

Natural Resources

Degree Name

Master of Science

First Advisor

Serita D Frey


Decay studies often observe that plant litter increases in the amount of nitrogen within the first year of decomposition, yet sources are uncertain. The Harvard Forest Chronic Nitrogen Amendment Experiment, Petersham, MA, was utilized to quantify vertical N translocation from soil up into decomposing litter and determine if long-term, chronic N application has affected this process. Litter bags were designed to facilitate or restrict fungal hyphal connectivity between the soil-litter interface and placed in control, low N+S and high N plots. After five or 12 months, a 15N-(NH 4)2SO4 solution was horizontally injected into organic soil beneath bags. 15N enrichment (i.e., translocation) of leaf litter was observed in high N fungi bags at 12 months. Similar quantities of fungal biomass-C across all N and litter bag treatments showed N translocation was not a factor of fungal establishment on litter, but rather leaf litter moisture, high soil-available N, and fungal hyphal bridges between the soil-litter interface.