Kommer emissioner av CO2 från små vattendrag att dubbla mängden av terrestärt kol som transporteras via akvatiska system? Källa och ålder av CO2 har svaret.

Tidsperiod: 2013-01-01 till 2015-12-31

Finansiär: Vetenskapsrådet

Bidragstyp: Projektbidrag

Budget: 2 850 000 SEK

In efforts to define how much carbon is being sequestered in the soil and vegetation, the importance of greenhouse gas (GHG) evasion from inland water that returns terrestrial C & N to the atmosphere via surface waters is increasingly recognized. Recent estimates put the magnitude of this aquatic conduit on a par with global Net Ecosystem Productivity. This project seeks to make regional estimates of the CO2, CH4 and N2O evading from running waters to the atmosphere in order to confirm the finding that this evasion is as large as or larger than all other types of C moving along the aquatic conduit in Sweden. We will then use delta13C and stream chemistry to determine the biogenic proportion of the evading CO2 in the regional study. In three representative catchments, we will go on to determine how much of this biogenic C in the aquatic conduit has been fixed from the atmosphere in recent decades as opposed to ?old? C released from peat that represents a loss from the long-term terrestrial C store. Two approaches will be used.Statistically representative sampling of GHG concentrations from hundreds of headwaters in different regions across Sweden where the biogenic of the CO2 will be ascertained from stream chemistry and 13C.2) Detailed transect studies to determine the origin and age of organic and inorganic C in water moving along catchment flow paths ways and then either downstream or back to the atmosphere.