Net ecosystem carbon and water fluxes of a calcareous grassland under elevated CO{sub 2}

Journal Article · Thu Jun 01 04:00:00 EDT 1995 · Bulletin of the Ecological Society of America

OSTI ID:95888

Stocker, R; Leadley, P; Niklaus, P ^[1]

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1. Univ. of Basel (Switzerland)

In 1994 we initiated a long term study on the effects of elevated CO{sub 2} on ecosystem function and biodiversity in a species rich grassland near Basel, Switzerland. Natural vegetation was exposed to ambient and elevated (600{mu}l 1{sup -1}) CO{sub 2} using open-top chambers. We measured ecosystem carbon and water fluxes for several 24hr. periods during the growing season by partially closing the top of the chambers. During the first 3 months of CO{sub 2} enrichment, mean net ecosystem carbon uptake at high photon flux density increased by 37%. The relative photosynthetic gain was diminished as photon flux density decreased. Dark respiration, and midday soil CO{sub 2}-evolution did not differ between treatments. Midday evapotranspiration decreased by 17%, probably due to stomatal responses, since LAI did not change. Since the extra carbon has not yet appeared in either aboveground, belowground, or microbial biomass, we hypothesize that a major part of the extra carbon was sequestered into the soil compartment.

• OSTI ID: 95888
• Report Number(s): CONF-9507129--
• Journal Information: Bulletin of the Ecological Society of America, Journal Name: Bulletin of the Ecological Society of America Journal Issue: 2 Vol. 76; ISSN BECLAG; ISSN 0012-9623
• Country of Publication: United States
• Language: English

Related Subjects

54 ENVIRONMENTAL SCIENCES
CARBON CYCLE
CARBON DIOXIDE
ECOLOGICAL CONCENTRATION
ENVIRONMENTAL EFFECTS
MOISTURE
RANGELANDS