Percent Photosynthesis (Net CO2 Exchange Rate) Increases for
300, 600 and 900 ppm Increases in the Air's CO2 Concentration:


For a more detailed description of this table, click here.

Pseudotsuga menziesii (Mirbel) Franco [Douglas Fir]


Statistics
 
300 ppm
600 ppm
900 ppm
 Number of Results
21
21
21
 Arithmetic Mean
25.9%
8.8%
11.3%
 Standard Error
5.1%
6
7.6%

Individual Experiment Results

Journal References

Experimental Conditions
300 ppm
600 ppm
900 ppm

Constable et al. (1999)

open-top chambers, 1996 needles in June 1996
42%

Constable et al. (1999)

open-top chambers, 1995 needles in June 1996
88%

Constable et al. (1999)

open-top chambers, 1996 needles in September 1996
24%

Hollinger (1987)

pots (4 liter)
31%

Lewis et al. (1999)

Terracosms, July 1996
38%

Lewis et al. (1999)

Terracosms, July 1996,elevated temperature
21%

Lewis et al. (1999)

Terracosms, January 1997
-16%

Lewis et al. (1999)

Terracosms, January 1997,elevated temperature
23%

Lewis et al. (1999)

Terracosms, April 1997
25%

Lewis et al. (1999)

Terracosms, April 1997,elevated temperature
46%

Lewis et al. (1999)

Terracosms, July 1997
24%

Lewis et al. (1999)

Terracosms, July 1997,elevated temperature
15%

Lewis et al. (2001)

Photosynthesis of two-year-old seedlings grown for an additional two years within sunlit controlled-environment chambers, with measurements made throughout years 3 and 4 on intact fully expanded unshaded needles from the most recent needle cohorts
32%

Lewis et al. (2004)

Two-yearl-old seedlings grown for 21 additional months in sunlit climate-controlled chambers maintained at soil water contents typical of the wet winter and dry summer climate of the U.S. Pacific Northwest
20%

Phillips et al. (2008)

Photosynthesis of crowns of 20-year-old trees growing naturally at 900 ppm extra CO2

112%

Phillips et al. (2008)

Photosynthesis of crowns of 20-year-old trees growing naturally at 300 ppm extra CO2
50%

Phillips et al. (2008)

Crown photosynthesis of 500-year-old trees growing naturally at 300 ppm extra CO2
62%

Phillips et al. (2008)

Crown photosynthesis of 500-year-old trees growing naturally at 600 ppm extra CO2

100%

Phillips et al. (2008)

Crown photosynthesis of 500-year-old trees growing naturally at 900 ppm extra CO2

125%

Phillips et al. (2008)

Photosynthesis of crowns of 20-year-old trees growing naturally at 600 ppm extra CO2

85%

Tingey et al. (2007)

Photosynthesis of two-year-old seedlings grown for an additional two years as closed-canopy plant-soil-litter systems within sunlit controlled-environment chambers, where measurements included all needle age classes and significant self shading
19%


Printer Friendly Version