Photosynthesis of a temperate fallow C3 herbaceous ecosystem: measurements and model simulations at the leaf and canopy levels

Title:

Photosynthesis of a temperate fallow C3 herbaceous ecosystem: measurements and model simulations at the leaf and canopy levels

Creator:

Gouasmi, M., Mordelet, P., Demarez, V., Gastellu-Etchegorry, J.-P., Le Dantec, V., Dedieu, G., Menaut, J.-C., Calvet, J.-C., and Lamaze, T.

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:b760d3a3-6da9-4fc4-8ee2-3488ee954ea4
uuid:b760d3a3-6da9-4fc4-8ee2-3488ee954ea4
issn:0300-3604
doi:10.1007/s11099-009-0053-0

Subject:

photosynthesis

Type:

model:article and TEXT

Format:

bez média and svazek

Description:

The objectives of the study were to characterize photosynthesis of temperate fallow C3 herbaceous species and examine the performance of a simple photosynthesis model (based on the Farquhar's equations) to simulate carbon fluxes at the leaf and canopy levels. The maximum rate of carboxylation at 25°C (V m0) was estimated for sunlit leaves using in situ gas exchange data under saturating irradiance. Throughout the seasons, leaf measurements indicate that values of V m0 were similar for the four major species of the fallow. The rate declined from March (100 µmol m-2 s-1) to July (50 µmol m-2 s-1) and remained almost constant until November. The maximum quantum yield estimated for Potentilla reptans L. (dominant species) was 0.082 mol(CO2) mol-1(photon absorbed), similar to values already published for C3 species. Leaf area index (LAI) increased from winter (less than 0.2 m2 m-2) to spring (up to 4 m2 m-2). Rates of canopy photosynthesis (measured with a canopy chamber) strongly depended on LAI and temperature, in addition to irradiance. They reached a maximum of 25 µmol m-2 s-1 and were intermediate between those published for C4 grassland or cultivated species, and on woody species. At leaf level, simulations gave realistic predictions. At canopy level, the model had the ability to reproduce the effects of environmental and seasonal conditions. However, simulations underestimated the photosynthetic activity of the fallow canopy. and M. Gouasmi ... [et al.].

Language:

Multiple languages

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Coverage:

331-339

Source:

Photosynthetica | 2009 Volume:47 | Number:3

Harvested from:

CDK

Metadata only:

false