Date of Award
Program or Major
Master of Science
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.
Burnham, Katharine M., "Saprotrophic fungi as a mechanism for vertical nitrogen transport in a chronically fertilized northern hardwood forest" (2011). Master's Theses and Capstones. 675.