Pacific Southwest

Title: Effect of ozone exposure on seasonal gas exchange of five western conifers

Author: Grulke, Nancy E.; Miller, Paul R.; Leininger, Theodor D.

Date: 1998

Source: In: Bytnerowicz, Andrzej; Arbaugh, Michael J.; Schilling, Susan L., tech. coords. Proceedings of the international symposium on air pollution and climate change effects on forest ecosystems. Gen. Tech. Rep. PSW-GTR-166. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 229-238

Station ID: GTR-PSW-166

Description: Five species of western conifers (Pinus ponderosa, Abies concolor, Pseudotsuga menziesii, Abies lasiocarpa, and Picea engelmannii) were exposed, in two standard open-top exposure chambers per treatment, to charcoal-filtered air and a simulated diurnal ozone exposure profile (120 d sum of 136 ppm-h) to test their relative sensitivity. CO₂ exchange rate (CER), stomatal conductance (gs), and total leaf nitrogen of current year foliage were measured at 1-month intervals. P. ponderosa was the most adversely affected by ozone, based on reductions in mid- and late season CER under saturating light (1.18 vs. 2.17 μmol CO₂ m^-2 s^-1), lower light compensation point (43 vs. 33 μmol quanta m^-2 s^-1), and lower CER at a given gs value. P. menziesii showed reduced CER and higher gs by the end of the experimental ozone exposure. A. concolor and P. engelmannii showed no reduction in CO₂ uptake and no clear effects of ozone exposure on gs. Adverse ozone effects on biomass or growth in the year of exposure were seen for A. lasiocarpa and P. ponderosa, whereas A. concolor, P. engelmanii and P. menziesii showed adverse effects only in the year after exposure. Few consistent patterns in which plant component was affected were found, either in the year of exposure or the year after exposure. An analysis of the number of chambers required or the difference between treatment means necessary to obtain statistical significance with the population variance measure was an important result.

Keywords: 

View and Print this Publication (350 KB)

Publication Notes: 

• We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
• This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
• You may send email to pubrequest@fs.f ed.us to request a hard copy of this publication. (Please specify exactly which publication you are requesting and your mailing address.)

 Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility

Citation

Grulke, Nancy E.; Miller, Paul R.; Leininger, Theodor D.  1998.  Effect of ozone exposure on seasonal gas exchange of five western conifers.   In: Bytnerowicz, Andrzej; Arbaugh, Michael J.; Schilling, Susan L., tech. coords. Proceedings of the international symposium on air pollution and climate change effects on forest ecosystems. Gen. Tech. Rep. PSW-GTR-166. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 229-238.