Claim · model-written summary
Douglas-fir leader growth was reduced in early 1990.
- Taxon
- Douglas-fir
Pseudotsuga menziesiit0 - Treatment
- ozonet0
- Outcome
- leader growthe0
- Direction
- reducede0
- Setting
- early 1990e0
Not reportedMaterialGeneCompoundOrgan / stageInteractorInteractor roleSecond interactorSecond interactor roleComparatorValueQualifier
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“reduced leader growth in early 1990.”
t0“ozone on the growth of Douglas-fir saplings”
Title
Wright, Elaine Frances cIRcle (University of British Columbia) 2009. doi:10.14288/1.0088872
Other claims from this paper (19)
- Observation The exposure treatments had unimodal concentrations fitting a Weibull distribution and diurnal profiles with mid-afternoon maxima.
- Association pea yield had a significant negative linear relationship with increasing D50 ozone exposure.
- Association potato yield had a significant negative linear relationship with increasing D50 ozone exposure.
- Association bean yield had a significant negative linear relationship with increasing D50 ozone exposure.
- Association radish yield had a significant negative linear relationship with increasing D50 ozone exposure.
- Association Final harvest total-plant, stem and leaf dry weights and leaf area decreased significantly under ozone exposure.
- Association Early-growth regressions did not reach significance even at p <0.10.
- Intervention effect Neither radish cultivar had significant ozone effects in the June experiment.
- Association Radish growth was significantly reduced in the July–August and August–September plantings.
- Association Absolute growth rates of all crops and cultivars declined significantly.
- Association Relative growth rates had variable responses, with reductions significant only at p <0.10.
- Association Several crops had increased relative growth rates early in growth.
- Observation Cherry Belle radish was more ozone-sensitive than French Breakfast.
- Association Douglas-fir second flush growth declined by the end of the second exposure season.
- Method / resource Nonlinear Weibull or gamma fits sometimes improved on linear regression but showed no consistent improvement.
- Method / resource Estimated flux gave poorer fits than D50 for radish growth measures.
- Method / resource Estimated flux improved Douglas-fir second flush growth fits over D50, with significant weight and leaf-area fits at final harvest in 1989.
- Method / resource FLUXSUMM fit better than D50 in 75 percent of comparisons, but only second flush weight at harvest 5 was significant.
- Observation The authors found limited support that flux estimates improve descriptions of growth responses over exposure indices.