Comparison of Carbon and Nitrogen Storage in Mineral Soils of Graminoid and Shrub Tundra Sites, Western Greenland
Shrub species are expanding across the Arctic in response to climate change and biotic interactions. Changes in belowground carbon (C) and nitrogen (N) storage are of global importance because Arctic soils store approximately half of global soil C. We collected ten (60 cm) soil cores each from grami...
| Main Authors: | , , , , |
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| Format: | Article in Journal/Newspaper |
| Language: | unknown |
| Published: |
NRC Research Press (a division of Canadian Science Publishing)
2016
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| Subjects: | |
| Online Access: | http://hdl.handle.net/1807/93884 http://www.nrcresearchpress.com/doi/abs/10.1139/AS-2015-0023 |
| Summary: | Shrub species are expanding across the Arctic in response to climate change and biotic interactions. Changes in belowground carbon (C) and nitrogen (N) storage are of global importance because Arctic soils store approximately half of global soil C. We collected ten (60 cm) soil cores each from graminoid- and shrub-dominated soils in western Greenland and determined soil texture, pH, C and N pools, and C:N ratios by depth for the mineral soil. To investigate the relative chemical stability of soil C between vegetation types, we employed a novel sequential extraction method for measuring organo-mineral C pools of increasing bond-strength. We found that: (i) mineral soil C and N storage was significantly greater under graminoids than shrubs (29.0 ± 1.8 versus 22.5 ± 3.0 kg C m-2 and 1.9 ± .12 versus 1.4 ± 1.9 kg N m-2); (ii) chemical mechanisms of C storage in the organo-mineral soil fraction did not differ between graminoid and shrub soils; and (iii) weak adsorption to mineral surfaces accounted for 40-60% of C storage in organo-mineral fractions— a pool that is relatively sensitive to environmental disturbance. Differences in these C pools suggest that rates of C accumulation and retention differ by vegetation type, which could have implications for predicting future soil C pool storage. The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author. |
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