Background: The eddy covariance (EC) technique provides a direct measure of water vapour and carbon dioxide fluxes between ecosystems and the atmosphere. Aims: This review article highlights the findings of… More

Considerable research has recently been devoted to understanding biogeochemical processes under winter snow cover, leading to enhanced appreciation of the importance of many winter ecological processes. In this study, a… More

We investigate the utility of an improved isotopic method to partition the net ecosystem exchange of CO2 (F) into net photosynthesis (FA) and nonfoliar respiration (FR). Measurements of F and… More

Stable isotopes provide insight into ecosystem carbon cycling, plant physiological processes, atmospheric boundary-layer dynamics, and are useful for the integration of processes over multiple scales. Of particular interest is the… More

Separation of the net ecosystem exchange of CO2 (F) into its component fluxes of net photosynthesis (FA) and nonfoliar respiration (FR) is important in understanding the physical and environmental controls… More

CO2 transport processes relevant for estimating net ecosystem exchange (NEE) at the Niwot Ridge AmeriFlux site in the front range of the Rocky Mountains, Colorado, USA, were investigated during a… More

The construction and deployment of a portable trace-gas measurement system (TGaMS) is described. The air-collection system (dubbed HYDRA) collects air samples from 18 different locations and was connected to either… More

Snowpack temperatures from a subalpine forest below Niwot Ridge, Colorado, are examined with respect to atmospheric conditions and the 30-min above-canopy and subcanopy eddy covariance fluxes of sensible Qh and… More

Sonic anemometers simultaneously measure the turbulent fluctuations of vertical wind (w’) and sonic temperature (Ts’), and are commonly used to measure sensible heat flux (H). Our study examines 30-min heat… More