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| Titel |
Measurement of carbon and water balances of semiarid scrubs using transient-state closed chambers |
| VerfasserIn |
Ana Lopez-Ballesteros, Oscar Perez-Priego, Enrique P. Sánchez-Cañete, Penelope Serrano-Ortíz, Francisco Domingo, Andrew S. Kowalski |
| Konferenz |
EGU General Assembly 2013
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| Medientyp |
Artikel
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| Sprache |
Englisch
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 15 (2013) |
| Datensatznummer |
250072097
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| Zusammenfassung |
| The measurement of canopy photosynthesis and transpiration is crucial to understand the
carbon and water cycles, specially, in water-limited ecosystems. When the objective is to
quantify fluxes of carbon at whole-plant level, scaling up from leaf to canopy by using
multi-layer models is always a tricky approach, because of the complexity in obtaining model
parameters within the canopy. Here we present a transient-state closed chamber, large enough
to measure medium-size plant gas exchanges in a semiarid shrubland. Additionally, a series
of tests were carried out to evaluate physical and physiological plant responses to potential
environmental modifications caused by the chamber. As results, leakage had a minimal
impact on flux calculations (0.9 % min-1), and chamber´s walls adsorption of water was not
detected. Furthermore, the artificial turbulence generated by fans into the chamber to
facilitate air mixing did not alter the transpiration rate. The optimal duration of the
calculation window was 60 s, which was the sufficient time interval to avoid the
disturbance of the enclosed plant. Maximum increases in air and plant temperature
were 0.6 ºC min-1 and 0.9 ºC min-1, respectively. Therefore, the minimal effects
that the chamber generated over the physiological processes of the enclosed plant
indicate that this chamber is suitable for accurate measurements of gas exchanges at
whole-plant scale in typical species that conform semiarid shrubland ecosystems. |
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