We compared vertical gradients in leaf gas exchange, CO2 concentrations, and refixation of respired CO2 in stands of Populus tremuloides Michx., Pinus banksiana Lamb. and Picea mariana (Mill.) B.S.P. at… More
Eddy covariance records hold great promise for understanding the processes controlling the net ecosystem exchange of CO2 (NEE). However, NEE is the small difference between two large fluxes: photosynthesis and… More
Some studies have reported that spring warming and earlier snowmelt leads to increased CO2sequestration in Arctic terrestrial ecosystems. We measured tundra-atmosphere CO2 exchange via eddy covariance at two low Arctic… More
We measured net atmospheric exchanges of energy and water vapor using eddy covariance along a chronosequence of Pinus elliottii plantations in north Florida: a recent clear-cut, a mid-rotation stand, and… More
Fluxes of CO2, latent heat and sensible heat were measured above a fully-leafed deciduous forest in eastern Tennessee with the eddy correlation technique. These are among the first reported observations… More
The largest biological fractionations of stable carbon isotopes observed in nature occur during production of methane by methanogenic archaea. These fractionations result in substantial (as much as ≈70‰) shifts in… More
Differences in the seasonal pattern of assimilatory and respiratory processes are responsible for divergences in seasonal net carbon exchange among ecosystems. Using FLUXNET data (http://www.eosdis.ornl.gov/FLUXNET) we have analyzed seasonal patterns… More
This paper reports the first effort to include carbon, water, and heat exchange in a Large Eddy Simulation (LES) model for 3D canopy flows with dynamic response of leaf temperature… More
Solar radiation and dew point temperature are important input variables for many crop growth ecological, hydrological, and meteorological models. It is also well known that solar radiation and dew point… More