Skip to Main Content
Cloud immersion alters microclimate, photosynthesis and water relations in Rhododendron catawbiense and Abies fraseri seedlings in the southern Appalachian Mountains, USAAuthor(s): Daniel M. Johnson; William K. Smith
Source: Tree Physiology, Vol. 28: 385-392
Publication Series: Scientific Journal (JRNL)
PDF: View PDF (1.36 MB)
DescriptionThe high altitude spruce-fir (Abies fraseri (Pursh) Poiret.-Picea rubens Sarg.) forests of the southern Appalachian Mountains, USA, experience frequent cloud immersion. Recent studies indicate that cloud bases may have risen over the past 30 years, resulting in less frequent forest cloud immersion, and that further increases in cloud base height are likely in the event of continued climate warming. To assess the impact of this trend on the regeneration of high altitude spruce-fir forests and the migration of plant communities, in particular the encroachment of spruce-fir forests and Rhododendron catawbiense Michx. islands into adjacent grass bald communities, we investigated effects of cloud immersion on photosynthetic parameters of seedlings of Abies fraseri and R. catawbiense in a grass bald site and A. fraseri in a forest understory. Although photosynthetic photon flux was 4.2 to 19.4-fold greater during clear conditions, cloud immersion had no effect on photosynthesis in A. jraseri at either site, whereas it reduced photosynthesis of R. catawbiense by about 40%. However, cloud immersion increased mean leaf fluorescence by 7.1 to 12.8% in both species at both sites. Cloud immersion increased mean relative humidity from 65 to 96%, reduced transpiration by 95% and reduced mean leaf-to-air temperature difference from 6.6 to 0.5 oC.
- You may send email to email@example.com to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- 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.
CitationJohnson, Daniel M.; Smith, William K. 2008. Cloud immersion alters microclimate, photosynthesis and water relations in Rhododendron catawbiense and Abies fraseri seedlings in the southern Appalachian Mountains, USA. Tree Physiology, Vol. 28: 385-392
Keywordsaltitude, climate change, diffuse light, fog, photo-inhibition, transpiration
- Cloud immersion alters microclimate, photosynthesis and water relations in Rhododendron catawbiense and Abies fraseri seedlings in the southern Appalachian Mountains, USA
- Impacts of cloud immersion on microclimate, photosynthesis and water relations of fraser fir in a temperate mountain cloud forest
- Decay of subalpine fir in Colorado
XML: View XML