Vedenpinnan muutoksen lyhytaikaiset vaikutukset hiilidioksidi- ja metaanipäästöihin peittosuolla
Laine A. M., Byrne K. A., Kiely G., Tuittila E.-S. Vedenpinnan muutoksen lyhytaikaiset vaikutukset hiilidioksidi- ja metaanipäästöihin peittosuolla.
English title: The short-term effect of altered water level on carbon dioxide and methane fluxes in a blanket bogTiivistelmä
Peatlands play an important role in the global carbon (C) cycle, by acting as a large, long-term C sink. The C sink is sustained by a high water level that inhibits decomposition of organic matter. The C gas dynamics are therefore sensitive to changes in water level, and in climatically different years a peatland can vary from a sink to a source of C. We measured carbon dioxide (CO2) and methane (CH4) fluxes from vegetation communities ranging from hummocks to low lawns in a blanket bog. After a one-year calibration period the water level was both lowered and raised experimentally and the changes in vegetation composition and gas fluxes were monitored during a further year. In all vegetation communities the water level drawdown increased the respiration rate and decreased methane emission; rising water level decreased respiration and increased methane emissions. The effect of altered water level on photosynthesis depended on species composition. Water level drawdown decreased photosynthesis in most communities; rising water level decreased the photosynthesis of hummocks species, and increased the photosynthesis of Rhynchospora alba.
Avainsanat
Sphagnum;
Drainage;
peatland;
methane;
flooding;
ecohydrology;
photosynthesis;
respiration;
Racomitrium;
Rhynchospora alba
Vastaanotettu 31.10.2017 Julkaistu 1.1.2009
Katselukerrat 1463
Saatavilla http://suo.fi/article/9868 | Lataa PDF