The effects of disturbance history, climate, and changes in atmospheric carbon dioxide (CO2) concentration and nitrogen deposition (Ndep) on carbon and water fluxes in seven North American evergreen forests are assessed using a coupled water–carbon–nitrogen model, canopy-scale flux observations, and descriptions …
Journal: Agricultural And Forest Meteorology, Volume 113 (1-4): 185-222 (2002). DOI: 10.1016/s0168-1923(02)00108-9 Sites: US-Ho1, US-Ho2, US-Ho3
A comprehensive evaluation of energy balance closure is performed across 22 sites and 50 site-years in FLUXNET, a network of eddy covariance sites measuring long-term carbon and energy fluxes in contrasting ecosystems and climates. Energy balance closure was evaluated by statistical regression of turbulent energy fluxes (sensible …
Journal: Agricultural And Forest Meteorology, Volume 113 (1-4): 223-243 (2002). DOI: 10.1016/s0168-1923(02)00109-0 Sites: US-Blo
The warm season (mid-June through late August) partitioning between sensible (H) and latent (LE) heat flux, or the Bowen ratio (β = H/LE), was investigated at 27 sites over 66 site years within the international network of eddy covariance sites (FLUXNET). Variability in β across ecosystems and …
Journal: Water Resources Research, Volume 38 (12): 1294-1305 (2002). DOI: 10.1029/2001wr000989 Sites: US-Blo
Eddy covariance measurements of carbon dioxide and water vapor exchange were made above a young and an old-growth ponderosa pine (Pinus ponderosa Dougl. ex P. & C. Laws) ecosystem located in a semiarid environment in central Oregon. The old-growth stand (O site) is a mixture of 250- and 50-year-old ponderosa …
Journal: Agricultural And Forest Meteorology, Volume 111 (3): 203-222 (2002). DOI: 10.1016/s0168-1923(02)00021-7 Sites: US-Me4, US-Me5
Carbon (C) exchange of a ∼200-year-old eastern hemlock (Tsuga canadensis L.) forest in central Massachusetts, USA, was estimated from mid-October 2000 through October 2001 based on eddy covariance measurements and statistical modeling from microclimatic data. Measurements were made in 68% of the hours during the year of …
Journal: Tree Physiology, Volume 22 (15-16): 1079-1092 (2002). DOI: 10.1093/treephys/22.15-16.1079 Sites: US-Ha2
The success of many prairie restorations is not well documented. A restoration begun in 1975 at the Fermi National Accelerator Laboratory near Chicago, Illinois allows assessment …
Journal: Restoration Ecology, Volume 10 (4): 677-684 (2002). DOI: 10.1046/j.1526-100x.2002.01048.x Sites: US-IB1, US-IB2
Soil respiration is one of the largest and most important fluxes of carbon in terrestrial ecosystems. While eddy covariance methods are becoming widely used to measure nighttime total ecosystem respiration, the use of chambers placed over the soil is the most direct way of measuring respiration occurring within the soil and litter …
Journal: Agricultural And Forest Meteorology, Volume 113 (1-4): 21-37 (2002). DOI: 10.1016/s0168-1923(02)00100-4 Sites: US-Ho1
Journal: Tree Physiology, Volume 22 (4): 219-229 (2002). DOI: 10.1093/treephys/22.4.219 Sites: CA-Obs
Components of the energy budget were measured above a subalpine coniferous forest over two complete annual cycles. Sensible and latent heat fluxes were measured by eddy covariance. Bowen ratios ranged from 0.7 to 2.5 in the summer (June–September) depending upon the availability of soil water, but were considerably higher (∼3–6) …
Journal: Agricultural And Forest Meteorology, Volume 110 (3): 177-201 (2002). DOI: 10.1016/s0168-1923(01)00290-8 Sites: US-NR1
CO2 exchange was measured on the forest floor of a coastal temperate Douglas-fir forest located near Campbell River, British Columbia, Canada. Continuous measurements were obtained at six locations using an automated chamber system between April and December, 2000. Fluxes were measured every half hour by circulating chamber …
Journal: Agricultural And Forest Meteorology, Volume 110 (4): 299-317 (2002). DOI: 10.1016/s0168-1923(01)00294-5 Sites: CA-Ca1