TY - JOUR
T1 - An initial intercomparison of micrometeorological and ecological inventory estimates of carbon exchange in a mid-latitude deciduous forest
AU - Ehman, J. L.
AU - Schmid, H. P.
AU - Grimmond, C. S.B.
AU - Randolph, J. C.
AU - Hanson, P. J.
AU - Wayson, C. A.
AU - Cropley, F. D.
PY - 2002
Y1 - 2002
N2 - The role of mid-latitude forests in the sequestration of carbon (C) is of interest to an increasing number of scientists and policy-makers alike. Net CO2 exchange can be estimated on an annual basis, using eddy-covariance techniques or from ecological inventories of C fluxes to and from a forest. Here we present an intercomparison of annual estimates of C exchange in a mixed hardwood forest in the Morgan-Monroe State Forest, Indiana, USA for two years, 1998 and 1999. Based on eddy-covariance measurements made at 1.8 times canopy height from a tower, C uptake by the forest was 237 and 287 g C m-2y-1 for 1998 and 1999, respectively. For the same time period, biometric and ecophysiological measures and modelled estimates of all significant carbon fluxes within deciduous forests were made, including: change in living biomass, aboveground and belowground detritus production, foliage consumption, and forest floor and soil respiration. Using this ecological inventory method for these same two time periods, C uptake was estimated to be 271 and 377 g C m-2y-1, which are 14.3% and 31.4% larger, respectively, than the tower-based values. The relative change between this method's annual estimates is consistent with that of the eddy-covariance based values. Our results indicate that the difference in annual C exchange rates was due to reduced heterotrophic soil respiration in 1999.
AB - The role of mid-latitude forests in the sequestration of carbon (C) is of interest to an increasing number of scientists and policy-makers alike. Net CO2 exchange can be estimated on an annual basis, using eddy-covariance techniques or from ecological inventories of C fluxes to and from a forest. Here we present an intercomparison of annual estimates of C exchange in a mixed hardwood forest in the Morgan-Monroe State Forest, Indiana, USA for two years, 1998 and 1999. Based on eddy-covariance measurements made at 1.8 times canopy height from a tower, C uptake by the forest was 237 and 287 g C m-2y-1 for 1998 and 1999, respectively. For the same time period, biometric and ecophysiological measures and modelled estimates of all significant carbon fluxes within deciduous forests were made, including: change in living biomass, aboveground and belowground detritus production, foliage consumption, and forest floor and soil respiration. Using this ecological inventory method for these same two time periods, C uptake was estimated to be 271 and 377 g C m-2y-1, which are 14.3% and 31.4% larger, respectively, than the tower-based values. The relative change between this method's annual estimates is consistent with that of the eddy-covariance based values. Our results indicate that the difference in annual C exchange rates was due to reduced heterotrophic soil respiration in 1999.
KW - Biometry
KW - Carbon fluxes
KW - Deciduous forest
KW - Ecophysiology
KW - Eddy covariance
KW - Micrometeorology
KW - Net ecosystem production
KW - Net primary production
KW - Soil respiration
UR - http://www.scopus.com/inward/record.url?scp=0036296419&partnerID=8YFLogxK
U2 - 10.1046/j.1365-2486.2002.00492.x
DO - 10.1046/j.1365-2486.2002.00492.x
M3 - Article
AN - SCOPUS:0036296419
SN - 1354-1013
VL - 8
SP - 575
EP - 589
JO - Global Change Biology
JF - Global Change Biology
IS - 6
ER -