1. Old-Growth Carbon Sequestration in the Sylvania Wilderness Ottawa National Forest, U.P. Michigan Ankur Desai Penn State, Meteorology January 2002

2. Quantifying carbon sequestration potential of mid and late successional forests in the upper midwest PI: Eileen Carey (University of Minnesota – Forest Resources) Co-PIs: Ken Davis (Penn State - Meteorology) Paul Bolstad (University of Minnesota – Forest Resources) Margaret Davis (University of Minesota – Ecology, Evolution, Behavior) Proposal Title: Funding agency: Department of Energy, Terrestial Carbon Processes View to the south from flux tower

3. With additional technical support from: Bruce Cook – University of Minnesota, Forest Resources Ankur Desai – Penn State, Meteorology Bob Evans – Ottawa National Forest, Watersmeet, MI Art Johnston – Chequamegon National Forest, Park Falls, WI U.S. Forest Service, North Central Experiment Station: Jud Isebrands, Ron Teclaw, Aaron Berger Helen Lake View to the northeast from flux tower

4. Location Ottawa National Forest – Upper Peninsula Michigan To: Willow Creek, Lost Creek, WLEF

5. Location Sylvania Wilderness (tower just outside of wilderness area) 35 named lakes Mostly flat topography 6 km e. of Watersmeet, MI Hemlock, maple, basswood dominant stands (3-30 ha) 0.5% turnover rate 187 year average canopy lifetime for Hemlocks One of two remaining large old-growth sites in upper Great Lakes region Numerous studies of area (M. Davis, L. Frelich, etc…), 3000 year pollen record 8,500 ha (18,000 acres)

6. Location Near Helen Lake Maple dominant stands right by tower, hemlock dominant within radius, yellow birch Typical canopy DBH 40-70 cm, height 25-30 m Mostly flat topography In Lake Superior watershed, occasional lake effect snow Close to campground No Hodags have been spotted Site has some lakes to north and east, fewer to west and south

7. Why study old-growth forest fluxes? Assumed to be insignificant sink, possibly source of CO 2, largely based on simple conceptual models Very few actual measurements of NEE in old-growth Existing old-growth flux sites suggest old-growth may actually be strong carbon sinks. 100-yr old boreal-northern hardwood site in Maine had 2.1 Mg C ha -1 yr -1 NEE in 1996 (Hollinger et al., 1999). 450-yr Douglas fir site in Oregon had 2.3 Mg C ha -1 yr -1 in 1998 (Chen, 1999). On the other hand, NEE in 90-yr old Black spruce only 0.1 Mg C ha -1 yr -1 (Goulden et al., 1997). We need a way to infer change in NEE over time as younger forests age

8. Why study Sylvania wilderness? Only one of two remaining old-growth sites in upper Great Lakes regions. Can help predict future course of NEE as post-logging forests of the Great Lakes region mature. Sylvania has changed little over 1000 years. Close to ChEAS sites: Willow Creek, Lost Creek, WLEF. Can compare NEE and component fluxes among similar sites along a succesional gradient. Helen Lake?

9. Principal Objectives of study Characterize NEE of an undisturbed old-growth forest Quantify the relative response of old-growth versus regrowing forests to climate variability and climate change Determine to what degree component carbon fluxes differ between early and late successional stands Characterize how physiological processes change as function of tree or stand age Sylvania old-growth is a carbon sink The carbon sink is smaller than younger forests but not insignificant Overall respiration is greater than younger forests, though not necessarily due to increased stem respiration (maybe related to water limitations) More NPP is allocated belowground as trees slow in growth Hypotheses

10. Primary methods CO 2 /H 2 O Eddy fluxes CO 2 profile 37m tower Stem / Leaf respiration Sapflux Micrometeorology Soil/stump respiration Soil temp/moisture

11. Spring-Summer 2001 Preliminary site investigation Building the tower Measuring fluxes in the lab Working on Willow CreekTower safety training

12. Summer-Fall 2001 The control shed and storage area Inside the shed Another day, another climb… Look out below! Endless fieldwork…

13. Measurements CO 2 and H 2 O 10Hz Fluxes at 36 m using Licor 6262 and Campbell CSAT-3 Sonic CO 2 mixing ratio profile (.6, 1.8, 3, 7.6, 13.7, 21.3, 36 m) using Licor 6252 H 2 O mixing ratio profile (2, 21, 36 m) Air temperature profile (.6, 2, 7.6, 12, 18, 21, 24, 30, 36 m) Wind speed (8 and 36 m) Above canopy net radiation and direct PAR (36 m), ground-level PAR (1 m) Leaf wetness (36 m) Soil temperature and moisture profile (surface, 5, 10, 20, 50, 100 cm) Soil heat flux (7.5 cm) Precipitation (tipping-bucket), rain and snow (2 locations: open and shaded) Tree sap flux at 48 trees, north and south side, Granier-type probe Soil, stem and stump respiration on > 150 trees using Licor 6400 and 6200 Leaf area index measurement with LAI-2000 Canopy characterization in 40,000 m 2 area around tower Lost Creek Shed

14. Preliminary Results: Micrometeorology (9/17/01-10/5/01) Temp Pressure Wind spd Wind dir Dewpoint

15. Preliminary Results: Micrometeorology 2 (9/17/01-10/5/01) PAR H2OH2O Rainfall Soil H 2 O

16. Preliminary Results: H 2 O, Temp, Soil Fluxes (9/17/01-10/5/01) Sensible Latent Soil Net Rad

17. Preliminary Results: CO 2 Fluxes (9/17/01-10/5/01) CO 2 Storage NEE u*

18. Preliminary Results: CO 2 Profile (9/17/01-10/5/01)

19. Preliminary Results: Sap Fluxes (Sept. and Oct. 2001) Hemlock Sugar Maple Yellow Birch Ensemble average daily sap flow for three tree species in cm / hour (just direct flow, not volume or leaf area flow) South side of tree is light gray/dotted, north is dark gray/solid lines

20. Future Plans and Issues Continue year-round flux measurement. Fix up bugs, calibration, errors Simultaneous component (soil and stem) flux measurements at Willow Creek and Helen Lake (and Lost Creek, too) Possibly expand sap flux measurements Examine effect of lake on fluxes (look at fluxes based on wind direction) Compare micrometeorology between Willow Creek and Helen Lake (effect of different watershed, lake effect snow, etc…) Expand area of canopy characterization Increase leaf area index measurements Obtain and analyze aerial and remote sensing products (ASTER/MODIS?) Compare fluxes against roving flux tower? Compare fluxes against WLEF, other old-growth towers, other Ameriflux sites?

21. Conclusion The Sylvania Wilderness/Helen Lake old-growth flux experiment will add knowledge about NEE uptake as forests age, and allow for an additional point of flux comparison among ChEAS and Ameriflux sites.