Can the Contrasting Carbon Balances of Forestry-Drained Peatlands Be Explained by Different Priming Effects?

Authors:
Maiju Linkosalmi, Christina Biasi, Jukka Pumpanen, Jussi Heinonsalo, Aki Lindén, Kari Minkkinen, Tuomas Laurila and Annalea Lohila

Book:
Proceedings of the 14th International Peat Congress

Venue:
Stockholm

Keywords:
flux-measurements, forested-peatlands, isotopes, nutrient-status

Documentfile:
Linkosalmi et al 2012: Can the Contrasting Carbon Balances of Forestry-Drained Peatlands Be Explained by Different Priming Effec

Summary:

Theme X. Peatland carbon budgets and greenhouse gas (GHG) fluxes

SUMMARY

We measured soil respiration rates of two forestry drained peatlands (nutrient-rich and nutrient-poor site) in laboratory conditions. The nutrient-rich site has been previously observed to act as a carbon source whereas the nutrient-poor site is a carbon sink. We examined whether the decomposition of old peat is enhanced by root exudates (priming effect). This was studied at the natural abundance level (¹⁴C) and by adding ¹³C-labelled glucose to peat samples. The results show that the nutrient-rich peat is characterized by higher basal soil respiration rates. However negative priming or no priming was observed in both experiments and in both peat soils.