Skip to Main Content
U.S. Forest Service
Caring for the land and serving people
Caring for the land and serving people
United States Department of Agriculture
-
Ozone exposure and nitrogen deposition lowers root biomass of ponderosa pine in the San Bernardino Mountains, California
Author(s): Nancy Grulke; C.P. Andersen; M.E. Fenn; P.R. Miller
Date: 1998
Source: Environmental Pollution. 103: 63-73.
Publication Series: Scientific Journal (JRNL)
Station: Pacific Northwest Research Station
PDF: Download Publication (352.0 KB)Description
Decreased root biomass in forest trees in response to anthropogenic pollutants is believed to be one of the first steps in forest health degradation. Although decreased root biomass has been observed in controlled experiments, ozone effects on mature tree roots in natural stands has not previously been documented. Here we report standing root biomass of ponderosa pine at three sites in the San Bernardino Mountains distributed along a known, long-term pollution gradient of ozone and nitrogen deposition. Trees at each site were assessed for foliar ozone injury and below-ground attributes, in addition to other environmental factors known to influence root growth. During the period of peak root growth in the spring, root biomass at the least polluted site was 6-14 times greater than that observed at the most polluted site. Known differences in climatic and edaphic factors among the sites potentially contributing to the observed response were discounted as primary contributors to the response since in most cases the site differences would have driven the patterns of root growth in the opposite direction to that observed. Differences in biotic competitive interactions, also known to affect root growth, did not explain the observed pattern for the same reason. The data suggests that elevated ozone, high nitrogen deposition, and possibly other contributing factors such as soil acidification are primarily responsible for lowering root biomass in ponderosa pine stands in the San Bernardino Mountains. Published by Elsevier Science Ltd.Publication Notes
- Visit PNW's Publication Request Page to request a hard copy of this publication.
- 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.
Citation
Grulke, N.E.; Andersen, C.P.; Fenn, M.E.; Miller, P.R. 1998. Ozone exposure and nitrogen deposition lowers root biomass of ponderosa pine in the San Bernardino Mountains, California. Environmental Pollution. 103: 63-73.Keywords
Root biomass, Ponderosa pine, Ozone exposure, N deposition, root carbohydratesRelated Search
- Deciduous conifers: high n deposition and o3 exposure effects on growth and biomass allocation in ponderosa pine
- Structural injury underlying mottling in ponderosa pine needles exposed to ambient ozone concentrations in the San Bernardino Mountains near Los Angeles, California
- Predicting the effects of tropospheric ozone on regional productivity of ponderosa pine and white fir.
XML: View XML
Show More
Show Fewer
https://www.fs.usda.gov/treesearch/pubs/53854