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Abstract As Arctic regions warm rapidly, it is unclear whether high‐latitude soil carbon (C) will decrease or increase. Predicting future dynamics of Arctic soil C stocks requires a better understanding of the quantities and controls of soil C. We explore the relationship between vegetation and surface soil C in an understudied region of the Arctic: Baffin Island, Nunavut, Canada. We combined soil C data for three vegetation types—polar desert, mesic tundra, and wet meadow—with a vegetation classification to upscale soil C stocks. Surface soil C differed significantly across vegetation types, and interactions existed between vegetation type and soil depth. Polar desert soils were consistently mineral, with relatively thin organic layers, low percent C, and high bulk density. Mesic soils exhibited an organic‐rich epipedon overlying mineral soil. Wet meadows were consistently organic soil with low bulk density and high percent C. For the top 20 cm, polar desert contained the least soil C (2.17 ± 0.48 kg m−2); mesic tundra had intermediate C (8.92 ± 0.74 kg m−2); wet meadow stored the most C (13.07 ± 0.69 kg m−2). Extrapolating to the top 30 cm, our results suggest that approximately 44 Tg C is stored in the study region with a mean landscape soil C stock of 2.75 kg m−2for non‐water areas. Combining vegetation mapping with local soil C stocks considerably narrows the range of estimates from other upscaling approaches (27–189 Tg) for soil C on South Baffin Island.
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Vegetation type, soil biogeochemical data, and upscaled soil carbon on South Baffin Island, Nunavut, Canada, 2022
Predictions of how rapid warming will affect Arctic soil carbon (C) stocks are limited by an uneven sampling distribution across the pan-arctic region. Working in an understudied region of the Arctic, this project aims to improve our understanding of the quantities and controls on soil C. Specifically, we combined soil C data for three vegetation types, polar desert, mesic tundra, and wet meadow, with a vegetation classification to upscale soil C stocks on South Baffin Island. The uploaded dataset contains two sets of paired files. 1) Metadata and geochemistry files to report soil biogeochemical data from 51 soil cores collected on South Baffin Island in July, 2022. 2) A record of the code and dataset used to generate a vegetation classification and soil C upscaling estimate for the study region.
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- Award ID(s):
- 1802732
- PAR ID:
- 10554340
- Publisher / Repository:
- NSF Arctic Data Center
- Date Published:
- Subject(s) / Keyword(s):
- Soil carbon Upscaling Permafrost Biogeochemistry
- Format(s):
- Medium: X Other: text/xml
- Sponsoring Org:
- National Science Foundation
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