Publications: 2005-Present     2001-2004    1996-2000    1988-1995

2004   2003   2002   2001

2004 Publications

Hollinger D.Y., J. Aber, B. Dail, E.A. Davidson, S.M. Goltz, H. Hughes, M. Y Leclerc, J.T. Lee, A.D. Richardson, C. Rodrigues, N.A. Scott, D. Achuatavarier, and J. Walsh. 2004. Spatial and temporal variability in forest-atmosphere CO2 exchange. Global Change Biology, 10:1689-1706. (link)

A key paper based on NIGEC support that reports on sources of interannual variation in ecosystem C uptake and compares results from 2 towers in similar vegetation. Interannual variability was found to be much larger than spatial variability in C fluxes. This paper also presents and tests a model of ecosystem C exchange and presents estimates of C stocks in the forest.

Lai C. –T., J. R. Ehleringer, S. C. Wofsy, S. P. Urbanski, and D. Y. Hollinger. 2004. Estimating photosynthetic 13C discrimination in terrestrial CO2 exchange from canopy to regional scales. Global Biogeochemical Cycles 18: GB1041.

This paper presents an estimate of ecosystem discrimination for 13CO2, a critical parameter in many carbon cycle models, based on isotopic and flux data available from 4 sites.

Lin J.C., C. Gerbig, S.C. Wofsy, A.E. Andrews, B.C. Daube, C.A. Grainger, B.B. Stephens, P.S. Bakwin, D.Y. Hollinger. 2004. Measuring fluxes of trace gases at regional scales by Lagrangian observations: Application to the CO2 Budget and Rectification Airborne (COBRA) study. Journal Geophysical Research 109:D15304, 2004. (link)

This paper presents a case study of regional scale surface CO2 fluxes using data over the United States obtained in August 2000 in the CO2 Budget and Rectification Airborne (COBRA-2000) study. Howland flux data were used to parameterize the surface model.

Scott, N., C. A. Rodrigues, H. Hughes, J. T. Lee, E. A. Davidson, D. Bryan Dail, P. Malerba, D.Y. Hollinger. 2004. Changes in carbon storage and net carbon exchange one year after an initial shelterwood harvest at Howland Forest, ME. Environmental Management, Vol. 33, Supplement 1, pp. S9-S22. (link)

An accounting of onsite and offsite carbon gains and losses following a shelterwood harvest in an area adjacent to the main study area of the Howland forest.

Xiao X., D. Hollinger, J. Aber, M. Goltz, E. A. Davidson, Q. Zhang, and B. Moore III. 2004. Satellite-based modeling of gross primary production in an evergreen needleleaf forest. Remote Sensing of the Environment 89:519-534. (link)

A model of GPP driven by climate data and remotely-sensed Enhanced Vegetation Index (EVI) was developed for coniferous forest based on Howland flux data.

2003 Publications

Enquist B.J., E.P. Economo, T.E. Huxman, A.P. Allen, D.D. Ignace, and J.F. Gillooly. 2003. Scaling metabolism from organisms to ecosystems. Nature 423: 639-642.

A general model of ecosystem respiration based on the kinetics of metabolic reactions and the scaling of resource use by individual organisms is tested against data from CO2 flux measurement sites, including Howland.

Savage, K.E., and E.A. Davidson. 2003. A comparison of manual and automated systems for soil CO2 flux measurements: tradeoffs between spatial and temporal resolution. J. Exp. Botany 54:891-899.

Wilson K. B., D. D. Baldocchi, E. Falge, M. Aubinet, P. Berbigier, and others 2003. Diurnal centroid of ecosystem energy and carbon fluxes at FLUXNET sites. Journal of Geophysical Research Atmospheres 108 (D21):4664.

2002 Publications

Davidson, E.A., K. Savage, P. Bolstad, D.A. Clark, P.S. Curtis, D.S. Ellsworth, P.J. Hanson, B.E. Law, Y. Luo, K.S. Pregitzer, J.C. Randolph, and D. Zak. 2002. Belowground carbon allocation in forests estimated from litterfall and IRGA-based soil respiration measurements. Agriculture and Forest Meteorology 113:39-51.

A NIGEC/AmeriFlux synthesis product, comparing litterfall and soil respiration rates and their ratios across a range of temperate and tropical forests.

Davidson, E.A., K. Savage, L.V. Verchot, and R.I. Navarro. 2002. Minimizing artifacts and biases in chamber-based measurements of soil respiration. Agriculture and Forest Meteorology 113:21-37.

An analysis of sources of error and bias in chamber measurements of CO2 efflux from soils.

Falge, E., D. Baldocchi, J. Tenhunen, M. Aubinet, P. Bakwin, P. Berbigier, C. Bernhofer, G. Burba, R. Clement, K. J. Davis, J. A. Elbers, A. H. Goldstein, A. Grelle, A. Granier, J. Guðmundsson, D. Hollinger, A. S. Kowalski, G. Katul, B. E. Law, Y. Malhi, T. Meyers, R. K. Monson, J. W. Munger, W. Oechel, K. T. Paw U, K. Pilegaard, Ü. Rannik, C. Rebmann, A. Suyker, R. Valentini, K. Wilson, and S. Wofsy. 2002. Seasonality of ecosystem respiration and gross primary production as derived from FLUXNET measurements. Agricultural and Forest Meteorology 113:53-74.

A FLUXNET synthesis examining seasonality of respiration and GPP across a variety of ecosystem types.

Falge, E., J. Tenhunen, D. Baldocchi, M. Aubinet, P. Bakwin, P. Berbigier, C. Bernhofer, J. Bonnefond, G. Burba, R. Clement, K. J. Davis, J. A. Elbers, M. Falk, A. H. Goldstein, A. Grelle, A. Granier, T. Grünwald, J. Guðmundsson, D. Hollinger, I. A. Janssens, P. Keronen, A. S. Kowalski, G. Katul, B. E. Law, Y. Malhi, T. Meyers, R. K. Monson, E. Moors, J. W. Munger, W. Oechel, K. T. Paw U, K. Pilegaard, Ü. Rannik, C. Rebmann, A. Suyker, H. Thorgeirsson, G. Tirone, A. Turnipseed, K. Wilson and S. Wofsy. 2002. Phase and amplitude of ecosystem carbon release and uptake potentials as derived from FLUXNET measurements. Agricultural and Forest Meteorology 113:75-95.

A FLUXNET synthesis examining seasonality of carbon uptake and loss across a variety of ecosystem types.

Law, B. E., E. Falge, L. Gu, D. D. Baldocchi, P. Bakwin, P. Berbigier, K. Davis, A. J. Dolman, M. Falk, J. D. Fuentes, A. Goldstein, A. Granier, A. Grelle, D. Hollinger, I. A. Janssens, P. Jarvis, N. O. Jensen, G. Katul, Y. Mahli, G. Matteucci, T. Meyers, R. Monson, W. Munger, W. Oechel, R. Olson, K. Pilegaard, K. T. Paw U, H. Thorgeirsson, R. Valentini, S. Verma, T. Vesala, K. Wilson, and S. Wofsy. 2002. Environmental controls over carbon dioxide and water vapor exchange of terrestrial vegetation. Agricultural and Forest Meteorology 113:97-120.

Using data from FLUXNET sites, relationships between environmental variables and CO2 and water fluxes across a range of ecosystem types were presented. Mean annual temperature and site water balance explained much of the variation in gross photosynthesis.

Thornton, P.E., B. E. Law, H. L. Gholz, K. L. Clark, E. Falge, D. S. Ellsworth, A. H. Goldstein, R. K. Monson, D. Hollinger, M. Falk, J. Chen, and J.P. Sparks. 2002. Modeling and measuring the effects of disturbance history and climate on carbon and water budgets in evergreen needleleaf forests. Agricultural and Forest Meteorology 113:185-222.

The effects of interannual climate variability, disturbance history, and vegetation ecophysiology on carbon and water fluxes and storage at seven coniferous forests across the United States (including Howland) are integrated by the ecosystem process model Biome-BGC, with results compared to site biometric analyses and eddy covariance observations.

Wilson, KB, Baldocchi, DD, Aubinet, M, D. Hollinger and others. 2002. Energy partitioning between latent and sensible heat flux during the warm season at FLUXNET sites. Water Resources Research 38 (12): art. no.-1294.

The warm season (mid-June through late August) partitioning between sensible (H) and latent (LE) heat flux, or the Bowen ratio (beta=H/LE), was investigated at 27 sites over 66 site years within an international network of eddy covariance sites. Differences among vegetation types and climatic zones were observed.

2001 Publications

Baldocchi, D., E. Falge, L. Gu, R. Olsen, D. Hollinger and others. 2001. FLUXNET: A new tool to study the temporal and spatial variability of ecosystem-scale carbon dioxide, water vapor and energy flux densities. Bulletin of the American Meteorological Society 82:2415-2434.

The first review of early results from FLUXNET, the international network micrometeorological flux measurement sites that measure the exchanges of carbon dioxide, water vapor, and energy between the biosphere and atmosphere.

Falge, E, Baldocchi, D, Olson, R, et al. Gap filling strategies for long term energy flux data sets. 2001. Agric. and For. Met. 107:71-77.

The effect of gap filling method on annual sums of latent and sensible heat fluxes is examined using data from sites within the AmeriFlux (including Howland) and EUROFLUX networks.

Falge, E., D. Baldocchi, R. Olson, P. Anthoni, M. Aubinet, C. Bernhover, G. Burba, R. Ceulemans, R. Clement, H. Dolman, A. Granier, P. Gross, T. Grünwald, D. Hollinger, N. Jensen, G. Katul, P. Keronen, A. Kowalski, C.T. Lai, B. Law, T. Meyers, J. Moncrieff, E. Moors, J. Munger, K. Pilgaard, U. Rannik, C. Rebmann, A. Suyker, J. Tenhunen, K. Tu, S. Verma, T. Vesala, K. Wilson, and S. Wofsy. 2001. Gap filling strategies for defensible annual sums of net ecosystem exchange. 2001. Agricultural and Forest Meteorology 107:43-69.

This was the first paper to systematically evaluate a range of methods for gap filling eddy covariance time series of surface-atmosphere CO2 exchange. It was demonstrated the need for standardized methods if cross-site comparisons are to be made of annual sums of NEE. Data from a range of network sites were used in the analysis.

Gaudinski, J.B., S.E. Trumbore, E.A. Davidson, A.C. Cook, D. Markewitz, and D.D. Richter. 2001. The age of fine-root carbon in three forests of the eastern United States measured by radiocarbon. Oecologia 129:420-429.

Used radiocarbon measurements to estimate mean residence times of C in fine roots at Harvard, Howland, and Oak Ridge forests, demonstrating the surprisingly long mean lifetimes of these roots.

Savage, K.E., and E.A. Davidson. 2001. Interannual variation of soil respiration in two New England forests. Global Biogeochemical Cycles 15(2):337-351. (link)

Investigated interannual variation and controlling factors (summer drought, spring thaw, etc.) on soil respiration at Howland and Harvard forests.

Smith, K.T.; Shortle, W.C. 2001. Conservation of element concentration in xylem sap of red spruce. Trees: Structure and Function 15:148-153.

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