This project aims to investigate soil C allocation in a temperate mixed forest dominated by Quercus serrata, in particular contribution of respiration and production by external mycorrhizal mycelium.

In March 2011, nylon mesh bags (64 cm²),pore size 41 µm) filled with 60g dry sterile granite soil was installed in the top soil. The 41 µm pore size allows ingrowth of fungal hyphae but exclude roots. The filling of the bags makes it possible for mycorrhizal hyphae to enter the bag while hyphae from saprophytic fungi will not enter to the same extent. Bags was collected every second month. Direct after sampling the content of the ingrowth bag was emptied into a small respiration chamber and the CO₂ flux was measured with an infrared gas analyzer (GMP343, Vaisala, Finland). Samples where then transported to lab for biomass analyses.

Results show an increased CO₂ flux from May to July while from July to September the respiration is stable. This pattern could be due to high ingrowth of hyphae from March to July or a reflection of the soil temperature.