BayCEER Workshop 2023

Role of fungal hyphae to transfer carbon between deadwood and litter

Fungi are crucial decomposers of persistent degradable litter like deadwood, breaking down cellulose, hemicellulose, and lignin through enzymatic processes. Despite established knowledge on the transfer of nutrients and carbon compounds by fungal hyphae, little is understood about the impact of this transfer on litter decomposition. This study employed laboratory experiments to investigate: (a) if cellulose-Carbon (C) transfers from deadwood to the organic soil layer; (b) if beech deadwood transfers cellulose-C to spruce litter more effectively than spruce deadwood; (c) the effect of cellulose-C transfer on CO₂ production and microbial biomass in spruce litter; and (d) the specific fungal communities and enzyme activities involved. We employed four treatments using ¹³C-cellulose-labeled deadwood. Measurements of ¹³C ratios in respiration and microbial biomass in spruce litter were taken. The study confirmed that fungal hyphae do transfer carbon from deadwood to spruce litter, with the extent of transfer being tree species-dependent. Beech deadwood led to a significant increase in CO₂ production and microbial biomass in co-incubated spruce litter, as indicated by ¹³C signatures. These findings suggest avenues for future research, including the exploration of different litter types to understand cellulose-C transfer mechanisms more comprehensively.