Forest Carbon Storage in the Northern Midwest, USA: A Bottom-Up Scaling Approach Combining Local Meteorological and Biometric Data With Regional Forest Inventories

HR: 0800h
AN: B51C-0218 [Abstracts]
TI: Forest Carbon Storage in the Northern Midwest, USA: A Bottom-Up Scaling Approach Combining Local Meteorological and Biometric Data With Regional Forest Inventories
AU: * Curtis, P S
EM: curtis.7@osu.edu
AF: The Ohio State University, Dept. Evolution, Ecology, and Organismal Biology, Columbus, OH 43210-1293 United States
AU: Gough, C M
EM: gough.21@osu.edu
AF: The Ohio State University, Dept. Evolution, Ecology, and Organismal Biology, Columbus, OH 43210-1293 United States
AU: Vogel, C S
EM: csvogel@umich.edu
AF: The University of Michigan Biological Station, Biological Rd., Pellston, MI 49769 United States
AB: Carbon (C) storage increasingly is considered an important part of the economic return of forestlands, making easily parameterized models for assessing current and future C storage important for both ecosystem and money managers. For the deciduous forests of the northern midwest, USA, detailed information relating annual C storage to local site characteristics can be combined with spatially extensive forest inventories to produce simple, robust models of C storage useful at a variety of scales. At the University of Michigan Biological Station (45^o35`' N, 84^o42`' W) we measured C storage, or net ecosystem production (NEP), in 65 forest stands varying in age, disturbance history, and productivity (site index) using biometric methods, and independently measured net C exchange at the landscape level using meteorological methods. Our biometric and meteorological estimates of NEP converged to within 1% of each other over five years, providing important confirmation of the robustness of these two approaches applied within northern deciduous forests (Gough et al. 2005). We found a significant relationship between NEP, stand age ( A, yrs), and site index ( I_s, m), where NEP = 0.134 + 0.022 * (LN[ A* I_s]) (r² = 0.50, P < 0.02). Site index is an integrated measure of site quality, expressed as 50 yr canopy height. We then used stand age and site index data from forests of similar species composition reported in the USDA Forest Inventory and Analysis database (ncrs2.fs.fed.us/4801/fiadb/) to estimate forest C storage at different scales across the upper midwest, Great Lakes region. Model estimates were validated against independent estimates of C storage for other forests in the region. At the local ecosystem-level (~1 km²) C storage averaged 1.52 Mg ha^-1 yr^-1. Scaling to the two-county area surrounding our meteorological and biometric study sites, average stand age decreased and site index increased, resulting in estimated storage of 1.62 Mg C ha^-1 yr^-1, or 0.22 Tg C yr^-1 in the 1350 km² of deciduous forest in this area. For the state of Michigan (31,537 km² of deciduous forest), average uptake was estimated at 1.55 Mg C ha^-1 yr^-1, or 4.9 Tg C yr^-1 total storage. For the three state region encompassing Minnesota, Michigan, and Wisconsin (97,769 km² of deciduous forest), we estimated average storage in these forests of 1.51 Mg C ha^-1 yr^-1, or 14.1 Tg C yr^-1 total storage. This storage represents ~ 13 % of regional anthropogenic C emissions (US Department of Energy, 2003). This modest rate of C storage by forests in the region may decrease due to changes in forest succession and land-use, and also in response to climate-driven shifts in the balance between photosynthesis and respiration. Gough C.M., Vogel C.S., Schmid H.P., Su H.-B., and Curtis P.S. 2005. Multi-year convergence of biometric and meteorological estimates of forest carbon storage. Agricultural and Forest Meteorology, In Press.
DE: 0428 Carbon cycling (4806)
DE: 0439 Ecosystems, structure and dynamics (4815)
DE: 0466 Modeling
DE: 0476 Plant ecology (1851)
SC: Biogeosciences [B]
MN: Fall Meeting 2005