Black Carbon Contribution to Organic Carbon Stocks in Urban Soil

Jill L. Edmondson, Iain Stott, Jonathan Potter, Elisa Lopez-Capel, David A C Manning, Kevin J. Gaston, Jonathan R. Leake

Research output: Contribution to journalArticleResearchpeer-review

36 Citations (Scopus)


Soil holds 75% of the total organic carbon (TOC) stock in terrestrial ecosystems. This comprises ecosystem-derived organic carbon (OC) and black carbon (BC), a recalcitrant product of the incomplete combustion of fossil fuels and biomass. Urban topsoils are often enriched in BC from historical emissions of soot and have high TOC concentrations, but the contribution of BC to TOC throughout the urban soil profile, at a regional scale is unknown. We sampled 55 urban soil profiles across the North East of England, a region with a history of coal burning and heavy industry. Through combined elemental and thermogravimetic analyses, we found very large total soil OC stocks (31-65 kg m-2 to 1 m), exceeding typical values reported for UK woodland soils. BC contributed 28-39% of the TOC stocks, up to 23 kg C m-2 to 1 m, and was affected by soil texture. The proportional contribution of the BC-rich fraction to TOC increased with soil depth, and was enriched in topsoil under trees when compared to grassland. Our findings establish the importance of urban ecosystems in storing large amounts of OC in soils and that these soils also capture a large proportion of BC particulates emitted within urban areas.

Original languageEnglish
Pages (from-to)8339-8346
Number of pages8
JournalEnvironmental Science & Technology
Issue number14
Publication statusPublished - 21 Jul 2015
Externally publishedYes

Cite this