© 1995 Heron Publishing—Victoria, Canada
Effects of mist acidity and ambient ozone removal on montane red spruce
David R. Vann (1), G. Richard Strimbeck (2) and Arthur H. Johnson (2)
1. Department of Biology, University of Pennsylvania, Philadelphia, PA 19104-6018, USA / 2. Department of Geology, University of Pennsylvania, Philadelphia, PA 19104-6136, USA / Received August 8, 1994
Summary
Recent forest studies have established that high-elevation (> 900 m) populations of red spruce (Picea rubens Sarg.) in the northeastern USA are declining. Because it has been suggested that changes in air quality are responsible for
the decline, we examined the effects of acidic mists and ozone on several biochemical and growth parameters in mature montane
red spruce. We used branch-sized environmental chambers to introduce mists of controlled composition and exclude ambient clouds
and ozone from individual branches within a tree. Mists consisting of distilled water increased the end-of-season pigment
concentration and shoot length of enclosed branches relative to ambient or artificial mists. Needle and twig weights and starch
concentrations were not significantly altered by the acidic mist treatments. Removal of ambient ozone had no apparent effect
on the variables measured.
Keywords:
acid precipitation, artificial mist, chlorophyll loss, Picea rubens.
