D. Scott Mackay

Department of Geography
State University of New York
105 Wilkeson Quadrangle
Buffalo, NY 14261 USA

Phone: +1-716-645-0477
Fax: +1-716-645-2329

dsmackay at buffalo dot edu


Collaborative research: Restricted plasticity of canopy stomatal conductance: Conceptual basis for simplified models of canopy transpiration.

Funding Source: National Science Foundation, Directorate for Geosciences, Hydrological Sciences Division
Dates: April 1, 2004 to March 31, 2008.
Project Director: D. Scott Mackay
Co-Investigators: Brent E. Ewers (U. Wyoming), Eric L. Kruger (U. Wisconsin)

This project seeks a conceptual model of forest transpiration that embraces the spatial variability of stomatal control while retaining a tractable measure of generality that is the hallmark of empirical models of stomatal conductance. The conceptual model is based on the idea that canopy stomatal conductance is regulated primarily by water potential when water fluxes are high and of significant hydrologic import. It is hypothesized here that species plasticity in canopy stomatal conductance, which determines its spatial variability and challenge for quantifying, follows a linear relationship keyed to an easily quantifiable reference conductance. The knowledge gained from this research has broad implications for land surface modeling efforts directed at global change effects on water cycling. It will provide a relatively simple, but transportable and scientifically defensible, canopy model. Such models are essential foundations for the creation and implementation of credible policies aimed at mitigating or adjusting to the consequences of anticipated global change.

NSF Discoveries - Taking the Pulse of the Forest

LiveScience Article: Taking the Pulse of the Forest

Project Activities & Findings:
--> Click here for the detailed report
--> Click here for the graphics
--> Click here for a list of data products

Samanta, S., M.K. Clayton, D.S. Mackay, E.L. Kruger, and B.E. Ewers. 2008. Quantitative comparison of canopy conductance models using a Bayesian approach. Water Resources Research, in press.

Adelman, J.D., B.E. Ewers, and D.S. Mackay. 2008. Using temporal patterns in vapor pressure deficit to explain spatial autocorrelation dynamics in tree transpiration. Tree Physiology, 28, 657-658. [ please email for a pdf ]

Loranty, M.M., D.S. Mackay, B.E. Ewers, J.D. Adelman, and E.L. Kruger. 2008. Environmental drivers of spatial variation in whole-tree transpiration in an aspen-dominated upland-to-wetland forest gradient. Water Resources Research, 44, W02441, doi:10.1029/2007WR006272. [ please email for a pdf ]

Ewers, B.E., D.S. Mackay, J. Tang, P. Bolstad, and S. Samanta. 2008. Intercomparison of Sugar Maple (Acer saccharum Marsh.) stand transpiration responses to environmental conditions from the Western Great Lakes Region of the United State. Agricultural and Forest Meteorology, doi:10.1016/j.agrformet.2007.08.003, 148, 231-246. [ please email for a pdf ]

Samanta, S., D.S. Mackay, M. Clayton, E.L. Kruger, and B.E. Ewers. 2007. Bayesian analysis for uncertainty estimation of a canopy transpiration model. Water Resources Research, 43, W04424, doi:10.1029/2006WR005028. [ download ]

Mackay, D.S., B.E. Ewers, B.D. Cook, and K.J. Davis. 2007. Environmental drivers of evapotranspiration in a shrub wetland and an upland forest in northern Wisconsin, Water Resour. Res., 43, W03442, doi:10.1029/2006WR005149. [ download ]

Software Products (TBA)

Project Implications:
--> Click here for the detailed report

© D.S. Mackay 
Last Update: April 3, 2017