Presentation
Fine Spatial Scale Soil Water Content and CO2 Efflux Variability Through a Growing Season
American Geophysical Union Fall Meeting
(2016)
Abstract
Our understanding and quantification of fine temporal and spatial scale patterns of soil carbon and water dynamics across landscape scale environmental gradients is limited. For example, how does local scale soil CO2 efflux variability compare to its landscape scale pattern? How does plot scale CO2 efflux variability change across wet to dry landscape positions? We addressed these fundamental questions by assessing nested scales of CO2 flux variability within and across landscape positions at Tenderfoot Creek Experimental Forest through a growing season. We measured the spatial variability of CO2 fluxes and volumetric soil water content (VWC) in seven 700 m2 plots, two plots were located in the riparian zone and five were located in the uplands. We measured CO2 efflux and VWC biweekly at 30 randomly located sites within each plot. These fine spatial scale measurements were nested within weekly landscape scale sampling of 32 sites (25 upland, 7 riparian). There was higher variability of VWC in the riparian area than in the uplands, and this variability increased through the season (coefficient of variation (CV) up to 66%). Variability in CO2 flux had the opposite seasonal progression in both riparian and upland locations. In the uplands, variability in CO2 fluxes was lower at the landscape scale (CV= 31%-46%) that at the plot scale (CV= 32%-84%). Gradients of environmental variables that influence water and carbon cycling are created in complex terrain, which can lead to landscape scale mediation of local conditions. Assessing the nested scales of variability in heterogeneous landscapes can provide insight into variables mediating biogeochemical fluxes.
Disciplines
Publication Date
December 14, 2016
Location
San Francisco, CA
Citation Information
Kendra Elena Kaiser and Brian L. McGlynn. "Fine Spatial Scale Soil Water Content and CO2 Efflux Variability Through a Growing Season" American Geophysical Union Fall Meeting (2016) Available at: http://works.bepress.com/kendra-kaiser/17/