Abiotic and biotic controls on grassland carbon dynamics in changing environments
Event details
| Date | 08.11.2011 |
| Hour | 16:15 |
| Speaker | Dr Michael Bahn, Institute of Ecology, University of Innsbruck, AT |
| Location |
GR C0 01
|
| Category | Conferences - Seminars |
Global change has been identified as a major feedback mechanism on the global carbon cycle. Two predominant components of global change, i.e. changes in land use and climate have been taking place at particularly high rates in mountain areas. This talk will summarize major recent insights in effects of such global changes on the carbon dynamics of mountain grasslands. It will be shown that the management intensity of grasslands has distinct effects on the net ecosystem exchange of CO2 between the ecosystem and the atmosphere, abandonment reducing its major flux components photosynthesis and respiration. The underlying coupling between these two fluxes will be demonstrated from annual to diel timescales, using comparative transect studies, experiments and isotopic labelling. Implications of land management (grazing and cutting) on the coupling of carbon fluxes will be discussed. It will also be shown that effects of gradual climate warming on soil CO2 emissions, the largest source of CO2 from terrestrial ecosystems, are likely more strongly dependent on indirect effects of altered photosynthetic assimilate supply than on direct warming effects on respiratory processes. Finally, emerging evidence from ecosystem manipulation experiments testing effects of climate extremes (summer drought) on the C dynamics of mountain grassland will be presented and discussed.
Links
Practical information
- General public
- Free
Contact
- Dr Thomas Spiegelberger, ECOS