Publications

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Publications Found: 42

Modeling BRFAnd Radiation Regime Of Boreal And Tropical Forests
Gastellu-Etchegorry, J., Guillevic, P., Zagolski, F., Demarez, V., Trichon, V., Deering, D., Leroy, M.

Monitoring of forest evolution and functioning with remote sensing depends on canopy BRF (bidirectional reflectance factor) sensitivity to biophysical parameters and to canopy PAR (photosynthetically active radiation) regime. Here, we study the canopy BRF of a tropical (Sumatra) …


Journal: Remote Sensing Of Environment, Volume 68 (3): 281-316 (1999). DOI: 10.1016/s0034-4257(98)00119-9 Sites: CA-Oas, CA-Obs, CA-Ojp

Variability In Leaf-Level CO2 And Water Fluxes In Pinus Banksiana And Picea Mariana In Saskatchewan
Sullivan, J. H., Bovard, B. D., Middleton, E. M.
We measured seasonal and canopy-level gas exchange in two stands of jack pine (Pinus banksianaLamb.) and one stand of black spruce (Picea mariana (Mill.) B.S.P.) on relatively clear days from late May until mid-September 1994. Field measurements were made with a portable infrared gas analyzer, …


Journal: Tree Physiology, Volume 17 (8-9): 553-561 (1997). DOI: 10.1093/treephys/17.8-9.553 Sites: CA-Obs, CA-Ojp

A Physiological Basis For Biosphere-Atmosphere Interactions In The Boreal Forest: An Overview
Margolis, H. A., Ryan, M. G.
Interdisciplinary field experiments for global change research are large, intensive efforts that study the controls on fluxes of carbon, water, trace gases, and energy between terrestrial ecosystems and the atmosphere at a range of spatial scales. Forest ecophysiology can make significant contributions to …


Journal: Tree Physiology, Volume 17 (8-9): 491-499 (1997). DOI: 10.1093/treephys/17.8-9.491 Sites: CA-Man, CA-Oas, CA-Obs, CA-Ojp

Simulating Forest Productivity And Surface-Atmosphere Carbon Exchange In The BOREAS Study Region
Kimball, J. S., Thornton, P. E., White, M. A., Running, S. W.

A process-based, general ecosystem model (BIOME–BGC) was used to simulate daily gross primary production, maintenance and heterotrophic respiration, net primary production and net ecosystem carbon exchange of boreal aspen, jack pine and black spruce stands. Model simulations of daily net carbon exchange of the ecosystem (NEE) explained …


Journal: Tree Physiology, Volume 17 (8-9): 589-599 (1997). DOI: 10.1093/treephys/17.8-9.589 Sites: CA-Man, CA-Oas, CA-Obs, CA-Ojp

Controls Over Monoterpene Emissions From Boreal Forest Conifers
Lerdau, M., Litvak, M., Palmer, P., Monson, R.

We investigated controls over the emission of monoterpenes from two species of boreal forest conifers, black spruce (Picea mariana Miller (B.S.P.)) and jack pine (Pinus banksiana Lamb). Monoterpenes are important in plants as carbon-based defensive compounds and in the atmosphere as photochemically reactive compounds …


Journal: Tree Physiology, Volume 17 (8-9): 563-569 (1997). DOI: 10.1093/treephys/17.8-9.563 Sites: CA-Oas, CA-Obs, CA-Ojp

Vertical Gradients In Photosynthetic Gas Exchange Characteristics And Refixation Of Respired CO2 Within Boreal Forest Canopies
Brooks, J. R., Flanagan, L. B., Varney, G. T., Ehleringer, J. R.

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 the northern and southern boundaries of the central Canadian boreal forest. Midsummer …


Journal: Tree Physiology, Volume 17 (1): 1-12 (1997). DOI: 10.1093/treephys/17.1.1 Sites: CA-Man, CA-Oas, CA-Obs, CA-Ojp

Physiological Responses Of A Black Spruce Forest To Weather
Goulden, M. L., Daube, B. C., Fan, S., Sutton, D. J., Bazzaz, A., Munger, J. W., Wofsy, S. C.

We used eddy covariance to measure the net exchange of CO2 between the atmosphere and a black spruce (Picea mariana) forest in Manitoba for 16,500 hours from March 16, 1994 to October 31, 1996. We then partitioned net exchange into gross photosynthesis and respiration by estimating daytime respiration as a function …


Journal: Journal Of Geophysical Research: Atmospheres, Volume 102 (D24): 28987-28996 (1997). DOI: 10.1029/97jd01111 Sites: CA-Obs

Root Mass, Net Primary Production And Turnover In Aspen, Jack Pine And Black Spruce Forests In Saskatchewan And Manitoba, Canada
Steele, S. J., Gower, S. T., Vogel, J. G., Norman, J. M.

Root biomass, net primary production and turnover were studied in aspen, jack pine and black spruce forests in two contrasting climates. The climate of the Southern Study Area (SSA) near Prince Albert, Saskatchewan is warmer and drier in the summer and milder in the winter than the Northern Study Area (NSA) near Thompson, Manitoba, …


Journal: Tree Physiology, Volume 17 (8-9): 577-587 (1997). DOI: 10.1093/treephys/17.8-9.577 Sites: CA-Man, CA-Oas, CA-Obs, CA-Ojp

Transpiration Of A Boreal Pine Forest Measured By Branch Bag, Sap Flow And Micrometeorological Methods
Saugier, B., Granier, A., Pontailler, J. Y., Dufrene, E., Baldocchi, D. D.

Three independent methods were used to evaluate transpiration of a boreal forest: the branch bag, sap flow and eddy covariance methods. The branch bag method encloses several thousand needles and gives a continuous record of branch transpiration. The sap flow method provides a continuous record of sap velocity and an estimate of …


Journal: Tree Physiology, Volume 17 (8-9): 511-519 (1997). DOI: 10.1093/treephys/17.8-9.511 Sites: CA-Obs

Automated Measurements Of CO2 Exchange At The Moss Surface Of A Black Spruce Forest
Goulden, M. L., Crill, P. M.

We used an automated, multiplexing gas-exchange system to measure the net exchange of CO2 at the surfaces of three shady feather moss and three exposed sphagnum moss sites in a black spruce forest during 35 days at the end of the 1995 growing season. Midday gross photosynthesis was 0.5 to 1.0 μmol m−2 s−1


Journal: Tree Physiology, Volume 17 (8-9): 537-542 (1997). DOI: 10.1093/treephys/17.8-9.537 Sites: CA-Obs