Browsing by Author "Keenan, Trevor"
Now showing items 1-7 of 7
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Circadian Control of Global Isoprene Emissions
Keenan, Trevor; Niinemets, Ü (Nature Publishing Group, 2012)Circadian rhythms govern many aspects of our lives, and it is thought that earth-atmosphere interactions are similarly affected. In this correspondence, we show that reported circadian rhythms can be explained by a variety ... -
Forest ecosystem changes from annual methane source to sink depending on late summer water balance
Shoemaker, Julie K.; Keenan, Trevor; Hollinger, David Y.; Richardson, Andrew (Wiley-Blackwell, 2014)Forests dominate the global carbon cycle, but their role in methane (CH4) biogeochemistry remains uncertain. We analyzed whole-ecosystem CH4 fluxes from 2 years, obtained over a lowland evergreen forest in Maine, USA. Gross ... -
Measures of Light in Studies on Light-Driven Plant Plasticity in Artificial Environments
Niinemets, Ülo; Keenan, Trevor (Frontiers Research Foundation, 2012)Within-canopy variation in light results in profound canopy profiles in foliage structural, chemical, and physiological traits. Studies on within-canopy variations in key foliage traits are often conducted in artificial ... -
Rate My Data: Quantifying the Value of Ecological Data for Models of Terrestrial Carbon Cycle
Keenan, Trevor; Davidson, Eric; Munger, James; Richardson, Andrew (Ecological Society of America, 2013)Primarily driven by concern about rising levels of atmospheric CO2, ecologists and earth system scientists are collecting vast amounts of data related to the carbon cycle. These measurements are generally time-consuming ... -
Terrestrial Biosphere Model Performance for Inter-Annual Variability of Land-Atmosphere CO2 Exchange
Keenan, Trevor; Baker, Ian; Barr, Alan; Ciais, Philippe; Dietze, Michael; Dragoni, Danillo; Gough, Christopher; Grant, Robert; Hollinger, David; Hufkens, Koen; Poulter, Ben; McCaughey, Harry; Racza, Brett; Ryu, Youngryel; Schaefer, Kevin; Tian, Hanqin; Verbeeeck, Hans; Zhao, Maosheng; Richardson, Andrew (Wiley-Blackwell, 2012)Interannual variability in biosphere-atmosphere exchange of CO2 is driven by a diverse range of biotic and abiotic factors. Replicating this variability thus represents the ‘acid test’ for terrestrial biosphere models. ... -
Tracking forest phenology and seasonal physiology using digital repeat photography: a critical assessment
Keenan, Trevor; Darby, B.; Felts, Libby Sophie; Sonnentag, O.; Friedl, M. A.; Hufkens, K.; O'Keefe, John Francis; Klosterman, Stephen; Munger, J. William; Toomey, M.; Richardson, Andrew (Ecological Society of America, 2014)Digital repeat photography is becoming widely used for near-surface remote sensing of vegetation. Canopy greenness, which has been used extensively for phenological applications, can be readily quantified from camera images. ... -
Using Model-Data Fusion to Interpret Past Trends, and Quantify Uncertainties in Future Projections, of Terrestrial Ecosystem Carbon Cycling
Keenan, Trevor; Davidson, Eric; Moffat, Antje; Munger, William; Richardson, Andrew (Wiley-Blackwell, 2012)Uncertainties in model projections of carbon cycling in terrestrial ecosystems stem from inaccurate parameterization of incorporated processes (endogenous uncertainties) and processes or drivers that are not accounted for ...