Claim · model-written summary
The most recent biogenic emissions model, assuming equal leaf and air temperatures, predicted July whole-tree emission rates fairly closely.
- Taxon
- white oak
Quercus albat0 - Outcome
- July whole‐tree emission ratese0
- Value
- fairly closelye0
Not reportedMaterialGeneCompoundOrgan / stageInteractorInteractor roleSecond interactorSecond interactor roleTreatmentComparatorSettingDirectionQualifier
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The most recently developed biogenic emissions model, which assumes that leaf and air temperatures are the same, predicted July whole‐tree emission rates fairly closely, although high emission rates were slightly underpredicted using the model”
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 whole-tree isoprene emissions increased from mid-May to a maximum in mid-July, with highest rates in late June and throughout July.
- 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 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.