Publications [#225330] of Emily S. Bernhardt
search .Papers Published
- Bernhardt, ES; Barber, JJ; Pippen, JS; Taneva, L; Andrews, JA; Schlesinger, WH, Long-term Effects of Free Air CO2 Enrichment (FACE) on Soil Respiration,
Biogeochemistry, vol. 77 no. 1
(January, 2006),
pp. 91-116 [doi] .
(last updated on 2023/01/01)Abstract:
Emissions of CO2 from soils make up one of the largest fluxes in the global C cycle, thus small changes in soil respiration may have large impacts on global C cycling. Anthropogenic additions of CO2 to the atmosphere are expected to alter soil carbon cycling, an important component of the global carbon budget. As part of the Duke Forest Free-Air CO2 Enrichment (FACE) experiment, we examined how forest growth at elevated (+200 ppmv) atmospheric CO2 concentration affects soil CO2 dynamics over 7 years of continuous enrichment. Soil respiration, soil CO 2 concentrations, and the isotopic signature of soil CO2 were measured monthly throughout the 7 years of treatment. Estimated annual rates of soil CO2 efflux have been significantly higher in the elevated plots in every year of the study, but over the last 5 years the magnitude of the CO2 enrichment effect on soil CO2 efflux has declined. Gas well samples indicate that over 7 years fumigation has led to sustained increases in soil CO2 concentrations and depletion in the δ 13C of soil CO2 at all but the shallowest soil depths. © Springer 2006.