Skip to Main Content
U.S. Forest Service
Caring for the land and serving people

United States Department of Agriculture

Home > Search > Publication Information

  1. Share via EmailShare on FacebookShare on LinkedInShare on Twitter
    Dislike this pubLike this pub
    Author(s): Michael Toomey; Mark A. Friedl; Steve Frolking; Koen Hufkens; Stephen Klosterman; Oliver Sonnentag; Dennis D. Baldocchi; Carl J. Bernacchi; Sebastien C. Biraud; Gil Bohrer; Edward Brzostek; Sean P. Burns; Carole Coursolle; David Y. Hollinger; Hank A. Margolis; Harry McCaughey; Russell K. Monson; J. William Munger; Stephen Pallardy; Richard P. Phillips; Margaret S. Torn; Sonia Wharton; Marcelo Zeri; Andrew D. Richardson
    Date: 2015
    Source: Ecological Applications
    Publication Series: Scientific Journal (JRNL)
    Station: Northern Research Station
    PDF: Download Publication  (3.0 MB)

    Description

    The proliferation of digital cameras co-located with eddy covariance instrumentation provides new opportunities to better understand the relationship between canopy phenology and the seasonality of canopy photosynthesis. In this paper we analyze the abilities and limitations of canopy color metrics measured by digital repeat photography to track seasonal canopy development and photosynthesis, determine phenological transition dates, and estimate intra-annual and interannual variability in canopy photosynthesis. We used 59 site-years of camera imagery and net ecosystem exchange measurements from 17 towers spanning three plant functional types (deciduous broadleaf forest, evergreen needleleaf forest, and grassland/crops) to derive color indices and estimate gross primary productivity (GPP). GPP was strongly correlated with greenness derived from camera imagery in all three plant functional types. Specifically, the beginning of the photosynthetic period in deciduous broadleaf forest and grassland/crops and the end of the photosynthetic period in grassland/crops were both correlated with changes in greenness; changes in redness were correlated with the end of the photosynthetic period in deciduous broadleaf forest.However, it was not possible to accurately identify the beginning or ending of the photosynthetic period using camera greenness in evergreen needleleaf forest. At deciduous broadleaf sites, anomalies in integrated greenness and total GPP were significantly correlated up to 60 days after the mean onset date for the start of spring. More generally, results from this work demonstrate that digital repeat photography can be used to quantify both the duration of the photosynthetically active period as well as total GPP in deciduous broadleaf forest and grassland/crops, but that new and different approaches are required before comparable results can be achieved in evergreen needleleaf forest.

    Publication Notes

    • Check the Northern Research Station web site to request a printed copy of this publication.
    • Our on-line publications are scanned and captured using Adobe Acrobat.
    • During the capture process some typographical errors may occur.
    • Please contact Sharon Hobrla, shobrla@fs.fed.us if you notice any errors which make this publication unusable.
    • 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

    Toomey, Michael; Friedl, Mark A.; Frolking, Steve; Hufkens, Koen; Klosterman, Stephen; Sonnentag, Oliver; Baldocchi, Dennis D.; Bernacchi, Carl J.; Biraud, Sebastien C.; Bohrer, Gil; Brzostek, Edward; Burns, Sean P.; Coursolle, Carole; Hollinger, David Y.; Margolis, Hank A.; McCaughey, Harry; Monson, Russell K.; Munger, J. William; Pallardy, Stephen; Phillips, Richard P.; Torn, Margaret S.; Wharton, Sonia; Zeri, Marcelo; Richardson, Andrew D. 2015. Greenness indices from digital cameras predict the timing and seasonal dynamics of canopy-scale photosynthesis. Ecological Applications. 25(1): 99-115. https://doi.org/10.1890/14-0005.1.

    Cited

    Google Scholar

    Keywords

    deciduous broadleaf forest, digital repeat photography, evergreen needleleaf forest, grassland, gross primary productivity, PhenoCam, phenology, photosynthesis, seasonality

    Related Search


    XML: View XML
Show More
Show Fewer
Jump to Top of Page
https://www.fs.usda.gov/treesearch/pubs/57051