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标题：Influence of Vegetation, Temperature, and Water Content on Soil Carbon Distribution and Mineralization in Four High Arctic Soils
其他标题：Influence of Vegetation, Temperature, and Water Content on Soil Carbon Distribution and Mineralization in Four High Arctic Soils
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作者：Bo Elberling ; Bjarne H. Jakobsen ; Peter Berg 等
期刊名称：Arctic, Antarctic, and Alpine Research
印刷版ISSN：1523-0430
电子版ISSN：1938-4246
出版年度：2004
卷号：36
期号：4
页码：528-538
DOI：10.1657/1523-0430(2004)036[0528:IOVTAW]2.0.CO%3B2
摘要：Soil organic matter distributions, reservoirs, and mineralization rates in tundra soils are important factors for understanding biogeochemical carbon cycling. This study focuses on spatial trends and environmental controls of soil carbon distribution and microbial soil respiration in 4 tundra vegetation communities in an arctic valley in NE-Greenland (74°N), including Dryas and Cassiope heaths, Salix snow bed, and fen vegetation. Measured total soil organic carbon in the upper 50 cm averaged (±SD) 11.0 ± 1.5 kg C m −2 with spatial variations strongly affected by vegetation, hydrology, and buried organic layers. Observed soil CO 2 concentrations and effluxes were simulated with a steady-state diffusion model using laboratory measured CO 2 productions as input. Simulated CO 2 profiles and CO 2 effluxes (up to 3 μmol CO 2 m −2 s −1 ) agreed with field observations and revealed the importance of both vegetation- and depth-specific CO 2 production and CO 2 diffusion for understanding the spatial variation in near-surface soil CO 2 gas dynamics. These results confirm that molecular diffusion dominates gas transport in the studied soils; but also that the complexity of CO 2 production/transport coupled to soil heterogeneity (in particular the litter layer) complicates the application of soil-diffusion models to estimate seasonal trends of soil gas effluxes.