Claim · model-written summary
White oak whole-tree isoprene emissions increased from mid-May to a maximum in mid-July, with highest rates in late June and throughout July.
- Taxon
- white oak
Quercus albat0 - Outcome
- Emissionse0
- Direction
- increasede0
- Qualifier
- mid‐May to a maximum in mid‐Julye0
Not reportedMaterialGeneCompoundOrgan / stageInteractorInteractor roleSecond interactorSecond interactor roleTreatmentComparatorSettingValue
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Emissions increased from mid‐May to a maximum in mid‐July”
t0“white oak”
Title
Seasonal isoprene emission rates and model comparisons using whole‐tree emissions from white oak
P. A. Pier; C. McDuffie Journal of Geophysical Research Atmospheres 1997. doi:10.1029/96jd03786
Other claims from this paper (12)
- Observation White oak isoprene emission rates decreased from early August to mid-October.
- Method / resource A model developed for whole-tree emissions accounted for 80% of the variability of observed emissions over the growing season.
- Observation Peak isoprene emissions and photosynthesis occurred at the same time, but peak emissions continued longer.
- Mechanism The authors suggest peak photosynthetic rates were not necessary for peak isoprene emissions.
- Method / resource Measured light intensities 2 m and 3.3 m down into the canopy corresponded to intensities estimated by current canopy models.
- Method / resource Light intensities at 1 m in the canopy were 14% lower than predicted by modeling.
- Observation Measured median leaf-to-air temperature difference was 2.0°C at the canopy top.
- Observation Measured median leaf-to-air temperature difference was 0.5°C or less within the canopy.
- Observation Median leaf temperatures estimated by a leaf energy balance procedure were slightly lower than air temperatures at all canopy levels, by not more than 0.9°C.
- Method / resource The most recent biogenic emissions model, assuming equal leaf and air temperatures, predicted July whole-tree emission rates fairly closely.
- Method / resource The same model slightly underpredicted high emission rates.
- Method / resource With previous canopy-model leaf temperature adjustments applied, predicted rates underestimated measured rates when measured rates exceeded 80 μg C g −1 h −1.