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- Maxwell, Tania L., et al.
(författare)
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Global dataset of soil organic carbon in tidal marshes
- 2023
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Ingår i: Scientific Data. - : Springer Nature. - 2052-4463. ; 10:1
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Tidskriftsartikel (refereegranskat)abstract
- Tidal marshes store large amounts of organic carbon in their soils. Field data quantifying soil organic carbon (SOC) stocks provide an important resource for researchers, natural resource managers, and policy-makers working towards the protection, restoration, and valuation of these ecosystems. We collated a global dataset of tidal marsh soil organic carbon (MarSOC) from 99 studies that includes location, soil depth, site name, dry bulk density, SOC, and/or soil organic matter (SOM). The MarSOC dataset includes 17,454 data points from 2,329 unique locations, and 29 countries. We generated a general transfer function for the conversion of SOM to SOC. Using this data we estimated a median (± median absolute deviation) value of 79.2 ± 38.1 Mg SOC ha−1 in the top 30 cm and 231 ± 134 Mg SOC ha−1 in the top 1 m of tidal marsh soils globally. This data can serve as a basis for future work, and may contribute to incorporation of tidal marsh ecosystems into climate change mitigation and adaptation strategies and policies.
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| 2. |
- Hugelius, Gustaf, et al.
(författare)
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Estimated stocks of circumpolar permafrost carbon with quantified uncertainty ranges and identified data gaps
- 2014
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Ingår i: Biogeosciences. - : Copernicus GmbH. - 1726-4170 .- 1726-4189. ; 11:23, s. 6573-6593
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Tidskriftsartikel (refereegranskat)abstract
- Soils and other unconsolidated deposits in the northern circumpolar permafrost region store large amounts of soil organic carbon (SOC). This SOC is potentially vulnerable to remobilization following soil warming and permafrost thaw, but SOC stock estimates were poorly constrained and quantitative error estimates were lacking. This study presents revised estimates of permafrost SOC stocks, including quantitative uncertainty estimates, in the 0-3m depth range in soils as well as for sediments deeper than 3m in deltaic deposits of major rivers and in the Yedoma region of Siberia and Alaska. Revised estimates are based on significantly larger databases compared to previous studies. Despite this there is evidence of significant remaining regional data gaps. Estimates remain particularly poorly constrained for soils in the High Arctic region and physiographic regions with thin sedimentary overburden (mountains, highlands and plateaus) as well as for deposits below 3mdepth in deltas and the Yedoma region. While some components of the revised SOC stocks are similar in magnitude to those previously reported for this region, there are substantial differences in other components, including the fraction of perennially frozen SOC. Upscaled based on regional soil maps, estimated permafrost region SOC stocks are 217 +/- 12 and 472 +/- 27 Pg for the 0-0.3 and 0-1 m soil depths, respectively (+/- 95% confidence intervals). Storage of SOC in 0-3m of soils is estimated to 1035 +/- 150 Pg. Of this, 34 +/- 16 PgC is stored in poorly developed soils of the High Arctic. Based on generalized calculations, storage of SOC below 3m of surface soils in deltaic alluvium of major Arctic rivers is estimated as 91 +/- 52 Pg. In the Yedoma region, estimated SOC stocks below 3mdepth are 181 +/- 54 Pg, of which 74 +/- 20 Pg is stored in intact Yedoma (late Pleistocene ice-and organic-rich silty sediments) with the remainder in refrozen thermokarst deposits. Total estimated SOC storage for the permafrost region is similar to 1300 Pg with an uncertainty range of similar to 1100 to 1500 Pg. Of this, similar to 500 Pg is in non-permafrost soils, seasonally thawed in the active layer or in deeper taliks, while similar to 800 Pg is perennially frozen. This represents a substantial similar to 300 Pg lowering of the estimated perennially frozen SOC stock compared to previous estimates.
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