1. Sap flux scaled canopy transpiration, stomatal conductance and water use efficiency in an old-growth forest in the Great Lakes region

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1. Sap flux scaled canopy transpiration,
stomatal conductance and water use efficiency in
an old-growth forest in the Great Lakes region
2. Carbon allocation in an old-growth
hemlock- northern hardwood forest in the Great
Lakes region
Jianwu Tang and coauthors
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Ongoing projects

• Respiration, production, and carbon allocation in
  Sylvania, Willow Creek, and Lost Creek spatial
  variation and successional patterns
• Canopy transpiration, stomatal conductance, and
  water use efficiency
• Cross-site soil respiration and automated
  measurement of soil respiration (half-hour)
  diurnal and seasonal variations and controls
• Upscaling
• Comparing Century-type carbon modeling with site
  measurements
• Comparing high-resolution-imagery-based upscaling
  with site measurements

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Transpiration stomatal conductance
photosynthesis Transpiration water use
efficiency photosynthesis
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Granier (1987)
Ewers et al. (1999) Oren et al. (1998)
Monteith and Unsworth (1990)
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Carbon allocation

• Important in ecosystem carbon modeling fixed
  allocation or not?
• Important in ecological theory

Odum, 1969, Science
Ryan et al. 1997, Ad. Eco. Res.
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a autotrophic, h heterotrophic, w wood, f
foliage, r root, s soil
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Carbon allocation (g C m-2 year-1)
                                                 
 
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Carbon (g C m-2) stored in forests
 
 
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NPP (g C m-2 y-1) from wood and foliage for three
species and their percentages in the hardwood and
hemlock stands
 
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Respiration per ground area (g C m-2 y-1) from
wood and foliage for three species and their
percentages in the hardwood and hemlock stands
 
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Conclusion

• Component respiration and production vary with
  ecosystem type and stand age.
• Transpiration studies can be coupled to carbon
  studies.