Aspects of Spatial and Temporal Aggregation in Estimating Regional Carbon DioxideFluxes from Temperate Forest Soils

摘要

The authors examine the influence of aggregation errors on developing estimatesof regional soil-CO2 flux from temperate forests. The authors find daily soil-CO2 fluxes to be more sensitive to changes in soil temperatures than air temperature. The direct use of mean monthly air temperature with a daily flux model underestimates regional fluxes by approximately 4%. Temporal aggregation error varies with spatial resolution. Overall, the authors' calibrated modeling approach reduces spatial aggregation error by 9.3% and temporal aggregation error by 15.5%. After minimizing spatial and temporal aggregation errors, mature temperature forest soils are estimated to contribute 12.9 Pg C/yr to the atmosphere as carbon dioxide. Georeferenced model estimates agree well with annual soil-CO2 fluxes measured during chamber studies in mature temporate forest stands around the globe. (Copyright (c) 1994, American Geographical Union.)