Dataset Information

Accuracy and Precision of Tidal Wetland Soil Carbon Mapping in the Conterminous United States.

ABSTRACT: Tidal wetlands produce long-term soil organic carbon (C) stocks. Thus for carbon accounting purposes, we need accurate and precise information on the magnitude and spatial distribution of those stocks. We assembled and analyzed an unprecedented soil core dataset, and tested three strategies for mapping carbon stocks: applying the average value from the synthesis to mapped tidal wetlands, applying models fit using empirical data and applied using soil, vegetation and salinity maps, and relying on independently generated soil carbon maps. Soil carbon stocks were far lower on average and varied less spatially and with depth than stocks calculated from available soils maps. Further, variation in carbon density was not well-predicted based on climate, salinity, vegetation, or soil classes. Instead, the assembled dataset showed that carbon density across the conterminous united states (CONUS) was normally distributed, with a predictable range of observations. We identified the simplest strategy, applying mean carbon density (27.0?kg C m^-3), as the best performing strategy, and conservatively estimated that the top meter of CONUS tidal wetland soil contains 0.72 petagrams C. This strategy could provide standardization in CONUS tidal carbon accounting until such a time as modeling and mapping advancements can quantitatively improve accuracy and precision.

SUBMITTER: Holmquist JR

PROVIDER: S-EPMC6013439 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Publications

Accuracy and Precision of Tidal Wetland Soil Carbon Mapping in the Conterminous United States.

Holmquist James R JR Windham-Myers Lisamarie L Bliss Norman N Crooks Stephen S Morris James T JT Megonigal J Patrick JP Troxler Tiffany T Weller Donald D Callaway John J Drexler Judith J Ferner Matthew C MC Gonneea Meagan E ME Kroeger Kevin D KD Schile-Beers Lisa L Woo Isa I Buffington Kevin K Breithaupt Joshua J Boyd Brandon M BM Brown Lauren N LN Dix Nicole N Hice Lyndie L Horton Benjamin P BP MacDonald Glen M GM Moyer Ryan P RP Reay William W Shaw Timothy T Smith Erik E Smoak Joseph M JM Sommerfield Christopher C Thorne Karen K Velinsky David D Watson Elizabeth E Grimes Kristin Wilson KW Woodrey Mark M

Scientific reports 20180621 1

Tidal wetlands produce long-term soil organic carbon (C) stocks. Thus for carbon accounting purposes, we need accurate and precise information on the magnitude and spatial distribution of those stocks. We assembled and analyzed an unprecedented soil core dataset, and tested three strategies for mapping carbon stocks: applying the average value from the synthesis to mapped tidal wetlands, applying models fit using empirical data and applied using soil, vegetation and salinity maps, and relying on ...[more]

PMID: 29930337

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Dataset Information

Accuracy and Precision of Tidal Wetland Soil Carbon Mapping in the Conterminous United States.

Publications

Accuracy and Precision of Tidal Wetland Soil Carbon Mapping in the Conterminous United States.

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