Main menu

WSL Home Forest Soil and cyclesSoil carbon

Soil carbon

Main menu

Soils play an important role in the global carbon cycle, as they can store large amounts of carbon dioxide (CO₂). In order to be able to assess the consequences of climate and land use changes, we investigate how soil, forests and the carbon cycle influence each other.

Temperature, moisture and litter inputs are the main controls on soil carbon cycling. Thus, changes in climate and land use affect C fluxes between soils, vegetation, and the atmosphere. This, in turn, determines if soils are a source or a sink for atmospheric CO₂.

In Switzerland, soils store about 80% of the terrestrial carbon and 7.5 times as much as the atmosphere as CO₂.

Objectives

How much and in which form is carbon stored in Swiss forest soils?
What are the effects of changes in climate and land-use?
How does increasing atmospheric CO₂ affect C dynamics in forest and alpine soils?
How is dissolved organic carbon (DOC) generated in soils? Which role does it play for C cycling?

Approaches

Field and lab experiments: we estimate the response of C fluxes and pools to increased soil temperatures and atmospheric CO₂ concentrations.
Carbon tracing: we apply stable isotope techniques to gain insight into soil C cycling.
Flux monitoring: measuring of C fluxes in forest ecosystems.
Carbon inventory: estimates of C stocks of Swiss forest soils.

FURTHER INFORMATION

Projects

Treeline in Ural

Historical photographs document that the upper treeline of the Ural mountains has moved up 60 to 80 m during the last century. We assess how the expansion of forests into tundra affects soil organic matter dynamics in the pristine Southern, Northern and Polar Ural.

Control on soil organic matter in Swiss forests

The cycling of carbon and nitrogen are closely linked and thus, the increasing deposition of nitrogen very likely affects soil organic matter dynamics. We are adding 13C and 15N labeled litter from beech to soils and investigate how experimentally increased N inputs influence the fate of litter-derived C and N.

Publications

Hagedorn, F.; Joseph, J.; Peter, M.; Luster, J.; Pritsch, K.; Geppert, U.; Kerner, R.; Molinier, V.; Egli, S.; Schaub, M.; Liu, J.; Li, M.; Sever, K.; Weiler, M.; Siegwolf, R.T.W.; Gessler, A.; Arend, M., 2016: Recovery of trees from drought depends on belowground sink control. Nature Plants, 2, 8: 16111 (5 pp.). doi: 10.1038/NPLANTS.2016.111

Dawes, M.A.; Schleppi, P.; Hättenschwiler, S.; Rixen, C.; Hagedorn, F., 2017: Soil warming opens the nitrogen cycle at the alpine treeline. Global Change Biology, 23, 1: 421-434. doi: 10.1111/gcb.13365

Ferrari, A.; Hagedorn, F.; Niklaus, P.A., 2016: Experimental soil warming and cooling alters the partitioning of recent assimilates: evidence from a ¹⁴C-labelling study at the alpine treeline. Oecologia, 181, 1: 25-37. doi: 10.1007/s00442-015-3427-y

Gavazov, K.; Hagedorn, F.; Buttler, A.; Siegwolf, R.; Bragazza, L., 2016: Environmental drivers of carbon and nitrogen isotopic signatures in peatland vascular plants along an altitude gradient. Oecologia, 180, 1: 257-264. doi: 10.1007/s00442-015-3458-4