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Most studies of forest structure,
carbon storage and carbon fluxes focus either on site-specific process
studies (for example, Ameriflux sites) or on very broad sampling (FIA, FHM) or proxies (remote
sensing). What is
needed are studies that bridge the gap between these scales. In a joint study with Forest Service
researchers and other collaborators across the country, we are measuring
carbon stocks and fluxes at the 10-square kilometer scale surrounding three
active process study sites: Ameriflux sites at GLEES and Niwot Ridge, and at Fraser Experimental Forest.
We are sampling using FIA sampling methods and plots and
adding additional measurements of fluxes and carbon stores to determine how
well the specific sites represent the landscape and learn how to extrapolate
to larger landscapes. We are also
using high spatial resolution LIDAR to measure structure over the entire 10
km2 study areas. These studies will allow
us to better estimate carbon stocks and fluxes for subalpine forest, and help
link carbon stocks and flux estimates to FIA samples. The LIDAR data will also
be used to estimate canopy and ground fuels, and
forest biomass and leaf area for the study areas useful for fire, forestry,
and hydrological modeling.
Some of the most interesting finds
so far have been that tree age (as sampled using FIA methods) is a poor indicator of
time since disturbance (Bradford et al. 2008a), that carbon stocks and fluxes
for subalpine forests stabiliize in < 100 years, independent of stand
history or climate (Bradford et al. 2008a), that fine-scale lidar can predict
many components of forest structure and carbon stocks well in subalpine
forests (Sherrill et al 2008), and that while the FIA plot design works well for change
detection, other sampling designs would be more efficient for assing carbon
at the landscape scale (Bradford et al. 2008b).
 
Brianna
Miles measuring tree heights
Tom Hayes measuring soil
respiration
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John
Bradford
Scott
Ollinger sampling foliage for N content
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Publications
Bradford
JB, RA Birdsey, LA Joyce and MG Ryan. 2008a. Tree age,
disturbance history, and carbon stocks and fluxes in subalpine Rocky Mountain
forests. Global Change Biology 14: 2882–2897.
Bradford
JB, P Weishampel, M-L Smith, RK Kolka, DY Hollinger, RA Birdsey, S Ollinger
and MG Ryan. 2008b. Landscape-Scale
Carbon Sampling Strategy – Lessons Learned. Pages 227-238 in CM Hoover, editor, Field
measurements for forest carbon monitoring: A landscape-scale approach,
Springer, New York, NY, USA.
Bradford
JB and MG Ryan. 2008c. Quantifying
soil respiration at landscape-scales.
Pages 143-162 in CM Hoover, editor, Field measurements for forest
carbon monitoring: A landscape-scale approach, Springer, New York, NY, USA.
Sherrill
KR, MA Lefsky, JB Bradford, and MG Ryan. 2008.
Forest
Structure Estimation and Pattern Exploration from Discrete Return Lidar in
Subalpine Forests of the Central Rockies.
Canadian Journal of Forest Research 38:2081–2096.
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