HR: 1340h
AN: B23A-0942    [Abstracts]
TI: Partitioned Soil Profile CO$_{2}$ Production in High and Low Resolution
AU: * Risk, D
EM: drisk@stfx.ca
AF: Environmental Earth Sciences Laboratory, St. Francis Xavier University, PO Box 5000, Antigonish, NS B2G 2W5 Canada
AU: Lisa, K
EM: lisa@stfx.ca
AF: Environmental Earth Sciences Laboratory, St. Francis Xavier University, PO Box 5000, Antigonish, NS B2G 2W5 Canada
AU: Beltrami, H
EM: hugo@stfx.ca
AF: Environmental Earth Sciences Laboratory, St. Francis Xavier University, PO Box 5000, Antigonish, NS B2G 2W5 Canada
AB: Forest soil carbon exchanges are sensitive to changes in the physical environment associated with major disturbances such as forest management or climate change, which alter the distribution of roots and organic matter, heat and moisture through depth in soils. The individual responses of autotrophic and heterotrophic respiration ultimately determine the magnitude of feedback effects, shifts in temporal patterns, and relative importance of root and microbial respiration in forest soils. This paper reports preliminary findings of a project whose aim is to assess the physical controls on partitioned CO$_{2}$ production. Using trench plots and subsurface CO$_{2}$ measurements, autotropic and heterotrophic soil profile CO$_{2}$ production is being monitored at several forest sites, across a range of temporal resolutions from seasonal to 5 minute. A multi-layer diffusion model is being used to calculate CO$_{2}$ production values through depth, using soil diffusivity values obtained from in-situ diffusivity measurements. Emphasis will be given here to the spatial and temporal patterns of partitioned respiration, especially in the high-resolution record.
DE: 1615 Biogeochemical processes (4805)
DE: 0400 Biogeosciences
SC: Biogeosciences [B]
MN: 2004 AGU Fall Meeting