Publications

Publications Found: 1373

Responses Of Net Ecosystem Exchanges Of Carbon Dioxide To Changes In Cloudiness: Results From Two North American Deciduous Forests
Gu, L., Fuentes, J. D., Shugart, H. H., Staebler, R. M., Black, T. A.

We analyzed half-hourly tower-based flux measurements of carbon dioxide (CO2) from a boreal aspen forest and a temperate mixed deciduous forest in Canada to examine the influences of clouds on forest carbon uptake. We showed that the presence of clouds consistently and significantly increased the net ecosystem exchanges …


Journal: Journal Of Geophysical Research: Atmospheres, Volume 104 (D24): 31421-31434 (1999), ISBN . DOI: 10.1029/1999jd901068 Sites: CA-Cbo

Nitrogen Dry Deposition At An Ameriflux Site In A Hardwood Forest In The Midwest
Pryor, S. C., Barthelmie, R. J., Jensen, B.

This paper presents observations of ammonia, nitric acid and size segregated chemically speciated aerosols above the canopy of a secondary successional deciduous forest in Indiana during spring. Average nitric acid concentrations range between 0.1–1 µg m−3 and vertical gradients from 1 to 9 ng m−3 / m. …


Journal: Geophysical Research Letters, Volume 26 (6): 691-694 (1999), ISBN . DOI: 10.1029/1999gl900066 Sites: US-MMS

Spatial And Temporal Variation In The Carbon And Oxygen Stable Isotope Ratio Of Respired CO2 In A Boreal Forest Ecosystem
Flanagan, L. B., Kubien, D. S., Ehleringer, J. R.

We measured the stable isotope ratio of respired carbon dioxide at two spatial scales in a black spruce forest in northern Canada: CO2 released from the forest floor and CO2 released from the entire ecosystem at night. Despite wide variation in the δ13C values of organic matter among above-ground plant species, …


Journal: Tellus Series B-Chemical and Physical Meteorology., Volume 51 (2): n/a-n/a (1999), ISBN . DOI: 10.3402/tellusb.v51i2.16306 Sites: CA-Let

Boreas Flight Measurements Of Forest-Fire Effects On Carbon Dioxide And Energy Fluxes
Amiro, B., MacPherson, J. I., Desjardins, R. L.

Fire is the dominant stand-replacing agent in the Canadian boreal forest, but few quantitative measurements are available on the micrometeorological effects of fire. Airborne flux measurements during the BOREAS experiment were referenced to age of burn along a 500-km transect …


Journal: Agricultural And Forest Meteorology, Volume 96 (4): 199-208 (1999), ISBN . DOI: 10.1016/s0168-1923(99)00050-7 Sites: CA-Man

Measurements Of PAR Transmittance Within Boreal Forest Stands During BOREAS
Roujean, J.

This paper shows the results of solar flux measurements routinely collected within boreal conifer forests during BOREAS 1994. Such vegetation have open canopies with a high level of clumping and covered by crowns which yields strong directional effects on the spectral hemispherical …


Journal: Agricultural And Forest Meteorology, Volume 93 (1): 1-6 (1999), ISBN . DOI: 10.1016/s0168-1923(98)00110-5 Sites: CA-Obs, CA-Ojp

Influence Of Biotic Exchange And Combustion Sources On Atmospheric CO2 Concentrations In New England From Observations At A Forest Flux Tower
Potosnak, M. J., Wofsy, S. C., Denning, A. S., Conway, T. J., Munger, J. W., Barnes, D. H.

Hourly data for concentrations and fluxes of CO2 at 30 m in Harvard Forest (Petersham, Massachusetts) are analyzed using linear modeling to obtain regionally representative CO2 concentrations …


Journal: Journal Of Geophysical Research: Atmospheres, Volume 104 (D8): 9561-9569 (1999), ISBN . DOI: 10.1029/1999jd900102 Sites: US-Ha1

In Situ Measurements Of C2 -C10 Volatile Organic Compounds Above A Sierra Nevada Ponderosa Pine Plantation
Lamanna, M. S., Goldstein, A. H.

A fully automated gas chromatograph-flame ionization detector system was designed and built to measure ambient concentrations of C2-C10 volatile organic compounds, including many oxygenated compounds, without using liquid cryogen. It was deployed at Blodgett Forest Research Station in Georgetown, California, …


Journal: Journal Of Geophysical Research: Atmospheres, Volume 104 (D17): 21247-21262 (1999), ISBN . DOI: 10.1029/1999jd900289 Sites: US-Blo

An Approach To Spatially Distributed Modeling Of Net Primary Production (NPP) At The Landscape Scale And Its Application In Validation Of EOS NPP Products
Reich, P. B., Turner, D. P., Bolstad, P.

Substantial research seeks to improve estimates of ecosystem processes and fluxes at a range of scales, notably from the stand scale (<1 km2) using ecosystem physiology and eddy covariance techniques, to the landscape (∼102 km2) and …


Journal: Remote Sensing Of Environment, Volume 70 (1): 69-81 (1999), ISBN . DOI: 10.1016/s0034-4257(99)00058-9 Sites: CA-Man, US-KFB, US-Kon

Effects Of Climatic Variability On The Annual Carbon Sequestration By A Boreal Aspen Forest
Chen, W. J., Black, T. A., Yang, P. C., Barr, A. G., Neumann, H. H., Nesic, Z., Blanken, P. D., Novak, M. D., Eley, J., Ketler, R. J., Cuenca, R.

To evaluate the carbon budget of a boreal deciduous forest, we measured CO2 fluxes using the eddy covariance technique above an old aspen (OA) forest in Prince Albert National Park, Saskatchewan, Canada, in 1994 and 1996 as part of the Boreal Ecosystem-Atmosphere Study (BOREAS). We found that the OA forest is a strong …


Journal: Global Change Biology, Volume 5 (1): 41-53 (1999), ISBN . DOI: 10.1046/j.1365-2486.1998.00201.x Sites: CA-Oas

Interacting Influence Of Mycorrhizal Symbiosis And Competition On Plant Diversity In Tallgrass Prairie
Smith, M. D., Hartnett, D. C., Wilson, G. W.

In tallgrass prairie, plant species interactions regulated by their associated mycorrhizal fungi may be important forces that influence species coexistence and community structure; however, the mechanisms and magnitude of these interactions remain unknown. The objective of this study was to determine how interspecific competition, …


Journal: Oecologia, Volume 121 (4): 574-582 (1999), ISBN . DOI: 10.1007/s004420050964 Sites: US-KFB, US-Kon