Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Review Article
  • Published:

The black carbon cycle and its role in the Earth system

Abstract

Black carbon (BC) is produced by incomplete combustion of biomass by wildfires and burning of fossil fuels. BC is environmentally persistent over centuries to millennia, sequestering carbon in marine and terrestrial environments. However, its production, storage and dynamics, and therefore its role in the broader carbon cycling during global change, are poorly understood. In this Review, we discuss BC cycling across the land-to-ocean continuum. Wildfires are the main source of BC, producing 128 ± 84 teragrams per year. Negative climate–BC feedbacks could arise as wildfire increases with anthropogenic warming, producing more BC, which in turn will sequester carbon, but the magnitude of these effects are unknown. Most BC is stored in terrestrial systems with some transported to the ocean via rivers and the atmosphere. However, the oceanic BC budget is not balanced, with known BC removal fluxes exceeding BC inputs. We demonstrate these observed inconsistencies using a simple ocean box model, which highlights key areas of future research. Measurements of BC mineralization and export rates along the land-to-ocean continuum and quantification of previously unexplored sources of oceanic BC are needed to close the global BC budget.

Key points

  • Black carbon (BC) is produced from incomplete combustion of biomass and fossil fuels and persists for centuries to millennia in the environment.

  • BC production is expected to increase with increasing fire activity under anthropogenic warming and could act as a negative feedback to climate change.

  • BC is often divided into particulate and dissolved BC, which can have different environmental transport mechanisms, residence times and fates.

  • The largest BC pool is in the soil (160–200 petagrams (Pg) C globally). Rivers transport 43 ± 15 teragrams (Tg) BC per year; BC is cycled in other inland aquatic systems, but the global relevance of these processes is unknown.

  • Oceans store 12–14 Pg C of dissolved BC. The observed age of this BC (4,800 ± 620 14C years in the surface ocean, >20,000 14C years in the deep ocean) does not match expected ages based on mass balance estimates.

  • Future research must further explore the possibility that some of the dissolved BC in marine waters is not derived from terrestrial fires.

This is a preview of subscription content, access via your institution

Access options

Buy this article

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: BC characteristics.
Fig. 2: Climate–carbon cycle feedbacks involving fire.
Fig. 3: BC in terrestrial systems.
Fig. 4: Global dynamics of the BC cycle.
Fig. 5: BC processes across the Earth system.

Similar content being viewed by others

Data availability

The fluxes of PBC, radiocarbon ages of PBC and mapped river basins derive from ref.62. The fluxes of DBC within latitudinal ranges derive from ref.2. The magnitude of the global stocks, fluxes, and radiocarbon ages of BC shown in Fig. 4 derive from the studies cited in Table 1. The data set is on the PANGAEA data repository (www.pangaea.de) under the username alyshacoppola (connected to the ORCID ID https://orcid.org/0000-0002-9928-2786).

References

  1. Santin, C., Doerr, S. H., Preston, C. M. & Gonzalez-Rodriguez, G. Pyrogenic organic matter production from wildfires: a missing sink in the global carbon cycle. Glob. Change Biol. 21, 1621–1633 (2015).

    Article  Google Scholar 

  2. Jones, M. W. et al. Fires prime terrestrial organic carbon for riverine export to the global oceans. Nat. Commun. 11, 2791 (2020).

    Article  Google Scholar 

  3. Santín, C. et al. Towards a global assessment of pyrogenic carbon from vegetation fires. Glob. Change Biol. 22, 76–91 (2016).

    Article  Google Scholar 

  4. Bond, T. C. et al. Bounding the role of black carbon in the climate system: a scientific assessment. J. Geophys. Res. Atmos. 118, 5380–5552 (2013).

    Article  Google Scholar 

  5. Harrison, S. P. et al. The biomass burning contribution to climate–carbon-cycle feedback. Earth Syst. Dynam. 9, 663–677 (2018).

    Article  Google Scholar 

  6. Bowring, S. P. K., Jones, M. W., Ciais, P., Guenet, B. & Abiven, S. Pyrogenic carbon decomposition critical to resolving fire’s role in the Earth system. Nat. Geosci. 15, 135–142 (2022).

    Article  Google Scholar 

  7. Landry, J.-S. & Matthews, H. D. The global pyrogenic carbon cycle and its impact on the level of atmospheric CO2 over past and future centuries. Glob. Change Biol. 23, 3205–3218 (2017).

    Article  Google Scholar 

  8. Goldberg, E. D. Black Carbon in the Environment: Properties and Distribution (Wiley, 1985).

  9. Masiello, C. A. New directions in black carbon organic geochemistry. Mar. Chem. 92, 201–213 (2004).

    Article  Google Scholar 

  10. Azam, F. & Malfatti, F. Microbial structuring of marine ecosystems. Nat. Rev. Microbiol. 5, 782–791 (2007).

    Article  Google Scholar 

  11. Schmidt, M. W. I. et al. Persistence of soil organic matter as an ecosystem property. Nature 478, 49–56 (2011).

    Article  Google Scholar 

  12. Kleber, M. What is recalcitrant soil organic matter. Environ. Chem. 7, 320–332 (2010).

    Article  Google Scholar 

  13. Coppola, A. I. & Druffel, E. R. M. Cycling of black carbon in the ocean. Geophys. Res. Lett. 43, 4477–4482 (2016).

    Article  Google Scholar 

  14. Reisser, M., Purves, R. S., Schmidt, M. W. I. & Abiven, S. Pyrogenic carbon in soils: a literature-based inventory and a global estimation of its content in soil organic carbon and stocks. Front. Earth Sci. 4, 80 (2016).

    Article  Google Scholar 

  15. Jolly, W. M. et al. Climate-induced variations in global wildfire danger from 1979 to 2013. Nat. Commun. 6, 7537 (2015).

    Article  Google Scholar 

  16. Abatzoglou, J. T., Williams, A. P. & Barbero, R. Global emergence of anthropogenic climate change in fire weather indices. Geophys. Res. Lett. 46, 326–336 (2019).

    Article  Google Scholar 

  17. Jones, M. W. et al. Global and regional trends and drivers of fire under climate change. Rev. Geophys. 60, e2020RG000726 (2022).

    Article  Google Scholar 

  18. van der Werf, G. R. et al. Global fire emissions estimates during 1997–2016. Earth Syst. Sci. Data 9, 697–720 (2017).

    Article  Google Scholar 

  19. Yue, C. et al. How have past fire disturbances contributed to the current carbon balance of boreal ecosystems? Biogeosciences 13, 675–690 (2016).

    Article  Google Scholar 

  20. Walker, X. J. et al. Increasing wildfires threaten historic carbon sink of boreal forest soils. Nature 572, 520–523 (2019).

    Article  Google Scholar 

  21. Arora, V. K. & Melton, J. R. Reduction in global area burned and wildfire emissions since 1930s enhances carbon uptake by land. Nat. Commun. 9, 1326 (2018).

    Article  Google Scholar 

  22. Zheng, B. et al. Increasing forest fire emissions despite the decline in global burned area. Sci. Adv. 7, eabh2646 (2021).

    Article  Google Scholar 

  23. Jones, M. W., Santín, C., van der Werf, G. R. & Doerr, S. H. Global fire emissions buffered by the production of pyrogenic carbon. Nat. Geosci. 12, 742–747 (2019).

    Article  Google Scholar 

  24. Santín, C. et al. Carbon sequestration potential and physicochemical properties differ between wildfire charcoals and slow-pyrolysis biochars. Sci. Rep. 7, 11233 (2017).

    Article  Google Scholar 

  25. Sun, T. et al. Suppressing peatland methane production by electron snorkeling through pyrogenic carbon in controlled laboratory incubations. Nat. Commun. 12, 4119 (2021).

    Article  Google Scholar 

  26. Masiello, C. A. & Berhe, A. A. First interactions with the hydrologic cycle determine pyrogenic carbon’s fate in the Earth system. Earth Surf. Process. Landf. 45, 2394–2398 (2020).

    Article  Google Scholar 

  27. Fierce, L., Riemer, N. & Bond, T. C. Explaining variance in black carbon’s aging timescale. Atmos. Chem. Phys. 15, 3173–3191 (2015).

    Article  Google Scholar 

  28. Jurado, E., Dachs, J., Duarte, C. M. & Simo, R. Atmospheric deposition of organic and black carbon to the global oceans. Atmos. Environ. 42, 7931–7939 (2008).

    Article  Google Scholar 

  29. Jones, M. W. et al. Do regional aerosols contribute to the riverine export of dissolved black carbon? J. Geophys. Res. Biogeosci. 122, 2925–2938 (2017).

    Article  Google Scholar 

  30. Wang, X., Xu, C., Druffel, E. R. M., Xue, Y. & Qi, Y. Two black carbon pools transported by the Changjiang and Huanghe rivers in China. Glob. Biogeochem. Cycles 30, 1778 (2016).

    Article  Google Scholar 

  31. Coppola, A. I. et al. Marked isotopic variability within and between the Amazon river and marine dissolved black carbon pools. Nat. Commun. 10, 4018 (2019).

    Article  Google Scholar 

  32. Bao, H., Niggemann, J., Luo, L., Dittmar, T. & Kao, S. Aerosols as a source of dissolved black carbon to the ocean. Nat. Commun. 8, 510 (2017).

    Article  Google Scholar 

  33. Nakane, M., Ajioka, T. & Yamashita, Y. Distribution and sources of dissolved black carbon in surface waters of the Chukchi Sea, Bering Sea, and the North Pacific Ocean. Front. Earth Sci. 5, 34 (2017).

    Article  Google Scholar 

  34. Mori, Y., Nishioka, J., Fujio, S. & Yamashita, Y. Transport of dissolved black carbon from marginal sea sediments to the western North Pacific. Prog. Oceanogr. 193, 102552 (2021).

    Article  Google Scholar 

  35. Fang, Z., Yang, W., Chen, M. & Ma, H. Source and fate of dissolved black carbon in the Western South China sea during the Southwest Monsoon prevailing season. J. Geophys. Res. Biogeosci. 122, 2817 (2017).

    Article  Google Scholar 

  36. Wagner, S. et al. Investigating atmospheric inputs of dissolved black carbon to the Santa Barbara channel during the Thomas Fire (California, USA). J. Geophys. Res. Biogeosci. 126, e2021JG006442 (2021).

    Article  Google Scholar 

  37. van der Werf, G. R. et al. Global fire emissions and the contribution of deforestation, savanna, forest, agricultural, and peat fires (1997–2009). Atmos. Chem. Phys. 10, 11707–11735 (2010).

    Article  Google Scholar 

  38. Bostick, K. W., Zimmerman, A. R., Wozniak, A. S., Mitra, S. & Hatcher, P. G. Production and composition of pyrogenic dissolved organic matter from a logical series of laboratory-generated chars. Front. Earth Sci. 6, 43 (2018).

    Article  Google Scholar 

  39. Sawyer, R., Bradstock, R., Bedward, M. & Morrison, R. J. Soil carbon in Australian fire-prone forests determined by climate more than fire regimes. Sci. Total Environ. 639, 526–537 (2018).

    Article  Google Scholar 

  40. Santos, F., Rice, D. M., Bird, J. A. & Berhe, A. A. Pyrolysis temperature and soil depth interactions determine PyC turnover and induced soil organic carbon priming. Biogeochemistry 153, 47–65 (2021).

    Article  Google Scholar 

  41. Cheng, C.-H., Lehmann, J., Thies, J. E., Burton, S. D. & Engelhard, M. H. Oxidation of black carbon by biotic and abiotic processes. Org. Geochem. 37, 1477–1488 (2006).

    Article  Google Scholar 

  42. Zimmerman, A. R. Abiotic and microbial oxidation of laboratory-produced black carbon (biochar). Environ. Sci. Technol. 44, 1295–1301 (2010).

    Article  Google Scholar 

  43. Li, M. et al. Photochemical aging of soot in the aqueous phase: release of dissolved black carbon and the formation of 1O2. Environ. Sci. Technol. 53, 12311–12319 (2019).

    Article  Google Scholar 

  44. Abiven, S., Hengartner, P., Schneider, M. P. W., Singh, N. & Schmidt, M. W. I. Pyrogenic carbon soluble fraction is larger and more aromatic in aged charcoal than in fresh charcoal. Soil. Biol. Biochem. 43, 1615–1617 (2011).

    Article  Google Scholar 

  45. Marques, J. S. J. et al. Dissolved black carbon in the headwaters-to-ocean continuum of Paraíba Do Sul River, Brazil. Front. Earth Sci. 5, 11 (2017).

    Article  Google Scholar 

  46. Bostick, K. W. et al. Photolability of pyrogenic dissolved organic matter from a thermal series of laboratory-prepared chars. Sci. Total Environ. 724, 138198 (2020).

    Article  Google Scholar 

  47. Jones, M. W. et al. Environmental controls on the riverine export of dissolved black carbon. Glob. Biogeochem. Cycles 33, 849–874 (2019).

    Article  Google Scholar 

  48. Abney, R. B. & Berhe, A. A. Pyrogenic carbon erosion: implications for stock and persistence of pyrogenic carbon in soil. Front. Earth Sci. 6, 26 (2018).

    Article  Google Scholar 

  49. Bellè, S. L. et al. Key drivers of pyrogenic carbon redistribution during a simulated rainfall event. Biogeosciences 18, 1105–1126 (2021).

    Article  Google Scholar 

  50. Wagner, S., Ding, Y. & Jaffé, R. A new perspective on the apparent solubility of dissolved black carbon. Front. Earth Sci. 5, 75 (2017).

    Article  Google Scholar 

  51. Woo, S. H., Enders, A. & Lehmann, J. Microbial mineralization of pyrogenic organic matter in different mineral systems. Org. Geochem. 98, 18–26 (2016).

    Article  Google Scholar 

  52. Zimmermann, M. et al. Rapid degradation of pyrogenic carbon. Glob. Change Biol. 18, 3306–3316 (2012).

    Article  Google Scholar 

  53. Bostick, K. W. et al. Biolability of fresh and photodegraded pyrogenic dissolved organic matter from laboratory-prepared chars. J. Geophys. Res. Biogeosci. 126, e2020JG005981 (2021).

    Article  Google Scholar 

  54. Spokas, K. A. et al. Physical disintegration of biochar: an overlooked process. Environ. Sci. Technol. Lett. 1, 326–332 (2014).

    Article  Google Scholar 

  55. Singh, N., Abiven, S., Torn, M. S. & Schmidt, M. W. I. Fire-derived organic carbon in soil turns over on a centennial scale. Biogeosciences 9, 2847–2857 (2012).

    Article  Google Scholar 

  56. Kuzyakov, Y., Bogomolova, I. & Glaser, B. Biochar stability in soil: decomposition during eight years and transformation as assessed by compound-specific 14C analysis. Soil. Biol. Biochem. 70, 229–236 (2014).

    Article  Google Scholar 

  57. Rennert, T. et al. Does soil organic matter in mollic horizons of central/east European floodplain soils have common chemical features? CATENA 200, 105192 (2021).

    Article  Google Scholar 

  58. Wang, Q., Zhang, P.-J., Liu, M. & Deng, Z.-W. Mineral-associated organic carbon and black carbon in restored wetlands. Soil. Biol. Biochem. 75, 300–309 (2014).

    Article  Google Scholar 

  59. Ohlson, M., Kasin, I., Wist, A. N. & Bjune, A. E. Size and spatial structure of the soil and lacustrine charcoal pool across a boreal forest watershed. Quat. Res. 80, 417–424 (2013).

    Article  Google Scholar 

  60. Seidel, M. et al. Benthic–pelagic coupling of nutrients and dissolved organic matter composition in an intertidal sandy beach. Mar. Chem. 176, 150–163 (2015).

    Article  Google Scholar 

  61. Seidel, M. et al. Biogeochemistry of dissolved organic matter in an anoxic intertidal creek bank. Geochim. Cosmochim. Acta 140, 418–434 (2014).

    Article  Google Scholar 

  62. Coppola, A. I. et al. Global-scale evidence for the refractory nature of riverine black carbon. Nat. Geosci. 11, 584–588 (2018).

    Article  Google Scholar 

  63. Abney, R. B. et al. Pyrogenic carbon erosion after the Rim Fire, Yosemite National Park: the role of burn severity and slope. J. Geophys. Res. Biogeosci. 124, 432–449 (2019).

    Article  Google Scholar 

  64. Wozniak, A. S. et al. Molecular heterogeneity in pyrogenic dissolved organic matter from a thermal series of oak and grass chars. Org. Geochem. 148, 104065 (2020).

    Article  Google Scholar 

  65. Wagner, S., Cawley, K. M., Rosario-Ortiz, F. L. & Jaffe, R. In-stream sources and links between particulate and dissolved black carbon following a wildfire. Biogeochemistry 124, 145–161 (2015).

    Article  Google Scholar 

  66. Dittmar, T. et al. Continuous flux of dissolved black carbon from a vanished tropical forest biome. Nat. Geosci. 5, 618–622 (2012).

    Article  Google Scholar 

  67. Mayorga, E. et al. Young organic matter as a source of carbon dioxide outgassing from Amazonian rivers. Nature 436, 538–541 (2005).

    Article  Google Scholar 

  68. Martin, E. E. et al. Age of riverine carbon suggests rapid export of terrestrial primary production in tropics. Geophys. Res. Lett. 40, 5687–5691 (2013).

    Article  Google Scholar 

  69. Qi, Y. et al. Dissolved black carbon is not likely a significant refractory organic carbon pool in rivers and oceans. Nat. Commun. 11, 5051 (2020).

    Article  Google Scholar 

  70. Yamashita, Y., Kojima, D., Yoshida, N. & Shibata, H. Relationships between dissolved black carbon and dissolved organic matter in streams. Chemosphere 271, 129824 (2021).

    Article  Google Scholar 

  71. Drake, T. W. et al. Du feu à l’eau: source and flux of dissolved black carbon from the Congo river. Glob. Biogeochem. Cycles 34, e2020GB006560 (2020).

    Article  Google Scholar 

  72. Bao, H., Niggemann, J., Huang, D., Dittmar, T. & Kao, S.-J. Different responses of dissolved black carbon and dissolved lignin to seasonal hydrological changes and an extreme rain event. J. Geophys. Res. Biogeosci. 124, 479–493 (2019).

    Article  Google Scholar 

  73. Jaffé, R. et al. Global charcoal mobilization from soils via dissolution and riverine transport to the oceans. Science 340, 345–347 (2013).

    Article  Google Scholar 

  74. Wagner, S., Jaffé, R. & Stubbins, A. Dissolved black carbon in aquatic ecosystems. Limnol. Oceanogr. Lett. 3, 168–185 (2018).

    Article  Google Scholar 

  75. Xu, C., Xue, Y., Qi, Y. & Wang, X. Quantities and fluxes of dissolved and particulate black carbon in the Changjiang and Huanghe rivers, China. Estuaries Coasts 39, 1617 (2016).

    Article  Google Scholar 

  76. Wagner, S. et al. Molecular hysteresis: hydrologically driven changes in riverine dissolved organic matter chemistry during a storm event. J. Geophys. Res. Biogeosci. 124, 759–774 (2019).

    Article  Google Scholar 

  77. Roebuck, J. A., Medeiros, P. M., Letourneau, M. L. & Jaffe, R. Hydrological controls on the seasonal variability of dissolved and particulate black carbon in the Altamaha river, GA. J. Geophys. Res. Biogeosci. 123, 3055 (2018).

    Article  Google Scholar 

  78. Hohner, A. K., Rhoades, C. C., Wilkerson, P. & Rosario-Ortiz, F. L. Wildfires alter forest watersheds and threaten drinking water quality. Acc. Chem. Res. 52, 1234–1244 (2019).

    Article  Google Scholar 

  79. Ding, Y., Yamashita, Y., Dodds, W. K. & Jaffe, R. Dissolved black carbon in grassland streams: is there an effect of recent fire history? Chemosphere 90, 2557–2562 (2013).

    Article  Google Scholar 

  80. Myers-Pigg, A. N., Louchouarn, P. & Teisserenc, R. Flux of dissolved and particulate low-temperature pyrogenic carbon from two high-latitude rivers across the spring freshet hydrograph. Front. Mar. Sci. 4, 38 (2017).

    Article  Google Scholar 

  81. Roebuck, J. A., Seidel, M., Dittmar, T. & Jaffé, R. Land use controls on the spatial variability of dissolved black carbon in a subtropical watershed. Environ. Sci. Technol. 52, 8104–8114 (2018).

    Article  Google Scholar 

  82. Wagner, S., Dittmar, T. & Jaffe, R. Molecular characterization of dissolved black nitrogen via electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. Org. Geochem. 79, 21–30 (2015).

    Article  Google Scholar 

  83. Hanke, U. M. et al. What on earth have we been burning? Deciphering sedimentary records of pyrogenic carbon. Environ. Sci. Technol. 51, 12972–12980 (2017).

    Article  Google Scholar 

  84. Cotrufo, M. F. et al. Redistribution of pyrogenic carbon from hillslopes to stream corridors following a large montane wildfire. Glob. Biogeochem. Cycles 30, 1348–1355 (2016).

    Article  Google Scholar 

  85. Mensing, S. A., Michaelsen, J. & Byrne, R. A 560-year record of Santa Ana fires reconstructed from charcoal deposited in the Santa Barbara Basin, California. Quat. Res. 51, 295–305 (1999).

    Article  Google Scholar 

  86. Galeron, M.-A. et al. Lipoxygenase-induced autoxidative degradation of terrestrial particulate organic matter in estuaries: a widespread process enhanced at high and low latitude. Org. Geochem. 115, 78–92 (2018).

    Article  Google Scholar 

  87. Ward, N. D. et al. Where carbon goes when water flows: carbon cycling across the aquatic continuum. Front. Mar. Sci. 4, 7 (2017).

    Article  Google Scholar 

  88. Ward, N. D., Sawakuchi, H. O., Richey, J. E., Keil, R. G. & Bianchi, T. S. Enhanced aquatic respiration associated with mixing of clearwater tributary and turbid Amazon river waters. Front. Earth Sci. 7, 101 (2019).

    Article  Google Scholar 

  89. Regnier, P., Resplandy, L., Najjar, R. G. & Ciais, P. The land-to-ocean loops of the global carbon cycle. Nature 603, 401–410 (2022).

    Article  Google Scholar 

  90. Dittmar, T., Paeng, J., Gihring, T. M., Suryaputra, I. & Huettel, M. Discharge of dissolved black carbon from a fire-affected intertidal system. Limnol. Oceanogr. 57, 1171 (2012).

    Article  Google Scholar 

  91. Bianchi, T. S. The role of terrestrially derived organic carbon in the coastal ocean: a changing paradigm and the priming effect. Proc. Natl Acad. Sci. USA 108, 19473 (2011).

    Article  Google Scholar 

  92. Bengtsson, M. M., Attermeyer, K. & Catalán, N. Interactive effects on organic matter processing from soils to the ocean: are priming effects relevant in aquatic ecosystems? Hydrobiologia 822, 1–17 (2018).

    Article  Google Scholar 

  93. Stubbins, A., Niggemann, J. & Dittmar, T. Photo-lability of deep ocean dissolved black carbon. Biogeosciences 9, 1661–1670 (2012).

    Article  Google Scholar 

  94. Wagner, S. & Jaffe, R. Effect of photodegradation on molecular size distribution and quality of dissolved black carbon. Org. Geochem. 86, 1–4 (2015).

    Article  Google Scholar 

  95. Leonce, B. C., Harvey, O. R., Gryczynski, Z., Hockaday, W. C. & Adegboyega, N. F. Structure–energy–photochemical activity relationships in fluorophoric water-extracted organic matter from (un)charred plant materials. ACS EST. Water 1, 859–870 (2021).

    Article  Google Scholar 

  96. Goranov, A. I. et al. Photochemistry after fire: structural transformations of pyrogenic dissolved organic matter elucidated by advanced analytical techniques. Geochim. Cosmochim. Acta 290, 271–292 (2020).

    Article  Google Scholar 

  97. Amon, R. M. W. & Benner, R. Photochemical and microbial consumption of dissolved organic carbon and dissolved oxygen in the Amazon river system. Geochim. Cosmochim. Acta 60, 1783–1792 (1996).

    Article  Google Scholar 

  98. Seidel, M. et al. Seasonal and spatial variability of dissolved organic matter composition in the lower Amazon river. Biogeochemistry 131, 281–302 (2016).

    Article  Google Scholar 

  99. Fu, H. et al. Photochemistry of dissolved black carbon released from biochar: reactive oxygen species generation and phototransformation. Environ. Sci. Technol. 50, 1218–1226 (2016).

    Article  Google Scholar 

  100. Coppola, A. I., Ziolkowski, L. A., Masiello, C. A. & Druffel, E. R. M. Aged black carbon in marine sediments and sinking particles. Geophys. Res. Lett. 41, 2427–2433 (2014).

    Article  Google Scholar 

  101. Fang, Y. et al. Particulate and dissolved black carbon in coastal china seas: spatiotemporal variations, dynamics, and potential implications. Environ. Sci. Technol. 55, 788–796 (2021).

    Article  Google Scholar 

  102. Feng, N. et al. Semi-enclosed bays serve as hotspots for black carbon burial: a case study in Jiaozhou Bay, western Yellow Sea. Sci. Total Environ. 797, 149100 (2021).

    Article  Google Scholar 

  103. Masiello, C. A. & Druffel, E. R. M. Organic and black carbon 13C and 14C through the Santa Monica Basin sediment oxic–anoxic transition. Geophys. Res. Lett. 30, 1185 (2003).

    Article  Google Scholar 

  104. Xu, W. et al. Historical variation in black carbon deposition and sources to Northern China sediments. Chemosphere 172, 242–248 (2017).

    Article  Google Scholar 

  105. Fang, Y. et al. Flux and budget of BC in the continental shelf seas adjacent to Chinese high BC emission source regions. Glob. Biogeochem. Cycles 29, 957–972 (2015).

    Article  Google Scholar 

  106. Fang, Y. et al. Spatiotemporal trends of elemental carbon and char/soot ratios in five sediment cores from Eastern China marginal seas: indicators of anthropogenic activities and transport patterns. Environ. Sci. Technol. 52, 9704–9712 (2018).

    Article  Google Scholar 

  107. Hansell, D. A., Carlson, C. A., Repeta, D. J. & Schlitzer, R. Dissolved organic matter in the ocean a controversy stimulates new insights. Oceanography 22, 202–211 (2009).

    Article  Google Scholar 

  108. Dittmar, T. & Paeng, J. A heat-induced molecular signature in marine dissolved organic matter. Nat. Geosci. 2, 175–179 (2009).

    Article  Google Scholar 

  109. Ziolkowski, L. A. & Druffel, E. R. M. Aged black carbon identified in marine dissolved organic carbon. Geophys. Res. Lett. 37, L16601 (2010).

    Article  Google Scholar 

  110. Dittmar, T. in Biogeochemistry of Marine Dissolved Organic Matter 2nd edn (eds Hansell, D. A. & Carlson, C. A.) 369–388 (Academic, 2015).

  111. Zhang, X. et al. The hadal zone is an important and heterogeneous sink of black carbon in the ocean. Commun. Earth Environ. 3, 25 (2022).

    Article  Google Scholar 

  112. Yamashita, Y., Nakane, M., Mori, Y., Nishioka, J. & Ogawa, H. Fate of dissolved black carbon in the deep Pacific Ocean. Nat. Commun. 13, 307 (2022).

    Article  Google Scholar 

  113. Fang, Z. et al. Spatial characteristics and removal of dissolved black carbon in the western Arctic Ocean and Bering Sea. Geochim. Cosmochim. Acta 304, 178–190 (2021).

    Article  Google Scholar 

  114. Beaupré Steven, R. et al. Oceanic efflux of ancient marine dissolved organic carbon in primary marine aerosol. Sci. Adv. 5, eaax6535 (2019).

    Article  Google Scholar 

  115. Wagner, S. et al. Isotopic composition of oceanic dissolved black carbon reveals non-riverine source. Nat. Commun. 10, 5064 (2019).

    Article  Google Scholar 

  116. Podgorski, D. C. et al. Hydrocarbons to carboxyl-rich alicyclic molecules: a continuum model to describe biodegradation of petroleum-derived dissolved organic matter in contaminated groundwater plumes. J. Hazard. Mater. 402, 123998 (2021).

    Article  Google Scholar 

  117. Chacón-Patiño, M. L., Rowland, S. M. & Rodgers, R. P. Advances in asphaltene petroleomics. Part 1: asphaltenes are composed of abundant island and archipelago structural motifs. Energy Fuels 31, 13509–13518 (2017).

    Article  Google Scholar 

  118. Goranov, A. I., Schaller, M. F., Long, J. A., Podgorski, D. C. & Wagner, S. Characterization of asphaltenes and petroleum using benzenepolycarboxylic acids (BPCAs) and compound-specific stable carbon isotopes. Energy Fuels 35, 18135–18145 (2021).

    Article  Google Scholar 

  119. Estes, E. R. et al. Abiotic synthesis of graphite in hydrothermal vents. Nat. Commun. 10, 5179 (2019).

    Article  Google Scholar 

  120. Hawkes, J. A., Hansen, C. T., Goldhammer, T., Bach, W. & Dittmar, T. Molecular alteration of marine dissolved organic matter under experimental hydrothermal conditions. Geochim. Cosmochim. Acta 175, 68–85 (2016).

    Article  Google Scholar 

  121. Hawkes, J. A. et al. Efficient removal of recalcitrant deep-ocean dissolved organic matter during hydrothermal circulation. Nat. Geosci. 8, 856–860 (2015).

    Article  Google Scholar 

  122. Brünjes, J., Seidel, M., Dittmar, T., Niggemann, J. & Schubotz, F. Natural asphalt seeps are potential sources for recalcitrant oceanic dissolved organic sulfur and dissolved black carbon. Environ. Sci. Technol. https://doi.org/10.1021/acs.est.2c01123 (2022).

  123. Allen Kylie, D. et al. Biogenic formation of amorphous carbon by anaerobic methanotrophs and select methanogens. Sci. Adv. 7, eabg9739 (2021).

    Article  Google Scholar 

  124. Trilla-Prieto, N., Vila-Costa, M., Casas, G., Jiménez, B. & Dachs, J. Dissolved black carbon and semivolatile aromatic hydrocarbons in the ocean: two entangled biogeochemical cycles? Environ. Sci. Technol. Lett. 8, 918–923 (2021).

    Article  Google Scholar 

  125. Stubbins, A. et al. Utilizing colored dissolved organic matter to derive dissolved black carbon export by Arctic rivers. Front. Earth Sci. 3, 63 (2015).

    Article  Google Scholar 

  126. Toggweiler, J. R. Variation of atmospheric CO2 by ventilation of the ocean’s deepest water. Paleoceanography 14, 571–588 (1999).

    Article  Google Scholar 

  127. Mentges, A. et al. Microbial physiology governs the oceanic distribution of dissolved organic carbon in a scenario of equal degradability. Front. Mar. Sci. 7, 549784 (2020).

    Article  Google Scholar 

  128. Beaupré, S. R., Walker, B. D. & Druffel, E. R. M. The two-component model coincidence: evaluating the validity of marine dissolved organic radiocarbon as a stable-conservative tracer at Station M. Deep Sea Res. Part II 173, 104737 (2020).

    Article  Google Scholar 

  129. Marwick, T. R. et al. The age of river-transported carbon: a global perspective. Glob. Biogeochem. Cycles 29, 122–137 (2015).

    Article  Google Scholar 

  130. Rossel, P. E. et al. Thermally altered marine dissolved organic matter in hydrothermal fluids. Org. Geochem. 110, 73–86 (2017).

    Article  Google Scholar 

  131. McCarthy, M. D. et al. Chemosynthetic origin of 14C-depleted dissolved organic matter in a ridge-flank hydrothermal system. Nat. Geosci. 4, 32–36 (2011).

    Article  Google Scholar 

  132. Pohlman, J. W., Bauer, J. E., Waite, W. F., Osburn, C. L. & Chapman, N. R. Methane hydrate-bearing seeps as a source of aged dissolved organic carbon to the oceans. Nat. Geosci. 4, 37–41 (2011).

    Article  Google Scholar 

  133. Masiello, C. A. & Druffel, E. R. M. Black carbon in deep-sea sediments. Science 280, 1911–1913 (1998).

    Article  Google Scholar 

  134. Leifeld, J. et al. Pyrogenic carbon contributes substantially to carbon storage in intact and degraded northern peatlands. Land Degrad. Dev. 29, 2082–2091 (2018).

    Article  Google Scholar 

  135. Heinemeyer, A., Asena, Q., Burn, W. L. & Jones, A. L. Peatland carbon stocks and burn history: blanket bog peat core evidence highlights charcoal impacts on peat physical properties and long-term carbon storage. GEO Geogr. Environ. 5, e00063 (2018).

    Google Scholar 

  136. Zimmerman, A. R. & Mitra, S. Trial by fire: on the terminology and methods used in pyrogenic organic carbon research. Front. Earth Sci. 5, 95 (2017).

    Article  Google Scholar 

  137. Hammes, K. et al. Comparison of quantification methods to measure fire-derived (black/elemental) carbon in soils and sediments using reference materials from soil, water, sediment and the atmosphere. Glob. Biogeochem. Cycles 21, GB3016 (2007).

    Article  Google Scholar 

  138. Wagner, S. et al. Questions remain about the biolability of dissolved black carbon along the combustion continuum. Nat. Commun. 12, 4281 (2021).

    Article  Google Scholar 

  139. Medeiros, P. M. et al. Fate of the Amazon River dissolved organic matter in the tropical Atlantic Ocean. Glob. Biogeochem. Cycles 29, 677–690 (2015).

    Article  Google Scholar 

  140. Dittmar, T. & Koch, B. P. Thermogenic organic matter dissolved in the abyssal ocean. Mar. Chem. 102, 208–217 (2006).

    Article  Google Scholar 

  141. Fatayer, S. et al. Direct visualization of individual aromatic compound structures in low molecular weight marine dissolved organic carbon. Geophys. Res. Lett. 45, 5590–5598 (2018).

    Article  Google Scholar 

  142. Hindersmann, B. & Achten, C. Accelerated benzene polycarboxylic acid analysis by liquid chromatography–time-of-flight–mass spectrometry for the determination of petrogenic and pyrogenic carbon. J. Chromatogr. A 1510, 57–65 (2017).

    Article  Google Scholar 

  143. Petsch, S. T., Smernik, R. J., Eglinton, T. I. & Oades, J. M. A solid state 13C-NMR study of kerogen degradation during black shale weathering. Geochim. Cosmochim. Acta 65, 1867–1882 (2001).

    Article  Google Scholar 

  144. Chang, Z. et al. Benzene polycarboxylic acid — a useful marker for condensed organic matter, but not for only pyrogenic black carbon. Sci. Total Environ. 626, 660–667 (2018).

    Article  Google Scholar 

  145. Serrano, O., Rozaimi, M., Lavery, P. S. & Smernik, R. J. Organic chemistry insights for the exceptional soil carbon storage of the seagrass Posidonia australis. Estuar. Coast. Shelf Sci. 237, 106662 (2020).

    Article  Google Scholar 

  146. Verdugo, P. in Annual Review of Marine Science Vol. 4 (eds Carlson, C. A. & Giovannoni, S. J.) 375–400 (2012).

  147. Verdugo, P. et al. The oceanic gel phase: a bridge in the DOM-POM continuum. Mar. Chem. 92, 67–85 (2004).

    Article  Google Scholar 

  148. Mari, X. et al. Seasonal dynamics of atmospheric and river inputs of black carbon, and impacts on biogeochemical cycles in Halong Bay, Vietnam. Elementa 5, 75 (2017).

    Google Scholar 

  149. Fang, Y. et al. Large-river dominated black carbon flux and budget: a case study of the estuarine-inner shelf of East China Sea, China. Sci. Total Environ. 651, 2489–2496 (2019).

    Article  Google Scholar 

  150. Fang, Y. et al. Cycling and budgets of organic and black carbon in coastal Bohai Sea, China: impacts of natural and anthropogenic perturbations. Glob. Biogeochem. Cycles 32, 971–986 (2018).

    Article  Google Scholar 

  151. Fang, Z., Yang, W., Chen, M., Zheng, M. & Hu, W. Abundance and sinking of particulate black carbon in the western Arctic and Subarctic oceans. Sci. Rep. 6, 29959 (2016).

    Article  Google Scholar 

  152. Bianchi, T. S. et al. Positive priming of terrestrially derived dissolved organic matter in a freshwater microcosm system. Geophys. Res. Lett. 42, 5460–5467 (2015).

    Article  Google Scholar 

  153. Archanjo, B. S. et al. Chemical analysis and molecular models for calcium–oxygen–carbon interactions in black carbon found in fertile Amazonian anthrosoils. Environ. Sci. Technol. 48, 7445–7452 (2014).

    Article  Google Scholar 

  154. Lian, F. & Xing, B. Black carbon (biochar) in water/soil environments: molecular structure, sorption, stability, and potential risk. Environ. Sci. Technol. 51, 13517–13532 (2017).

    Article  Google Scholar 

  155. Lane, P. N. J., Sheridan, G. J. & Noske, P. J. Changes in sediment loads and discharge from small mountain catchments following wildfire in south eastern Australia. J. Hydrol. 331, 495–510 (2006).

    Article  Google Scholar 

  156. Marlon, J. R. et al. Reconstructions of biomass burning from sediment-charcoal records to improve data–model comparisons. Biogeosciences 13, 3225–3244 (2016).

    Article  Google Scholar 

  157. Zou, Y. et al. A new automatic statistical microcharcoal analysis method based on image processing, demonstrated in the Weiyuan section, Northwest China. Front. Earth Sci. 9, 9916 (2021).

    Article  Google Scholar 

  158. Hawthorne, D. & Mitchell, F. J. G. Identifying past fire regimes throughout the Holocene in Ireland using new and established methods of charcoal analysis. Quat. Sci. Rev. 137, 45–53 (2016).

    Article  Google Scholar 

  159. Joshi, I. D. et al. Assessing chromophoric dissolved organic matter (CDOM) distribution, stocks, and fluxes in Apalachicola Bay using combined field, VIIRS ocean color, and model observations. Remote Sens. Environ. 191, 359–372 (2017).

    Article  Google Scholar 

  160. Liblik, T. et al. Potential for an underwater glider component as part of the Global Ocean Observing System. Methods Oceanogr. 17, 50–82 (2016).

    Article  Google Scholar 

  161. Cyr, F., Tedetti, M., Besson, F., Bhairy, N. & Goutx, M. A glider-compatible optical sensor for the detection of polycyclic aromatic hydrocarbons in the marine environment. Front. Mar. Sci. 6, 110 (2019).

    Article  Google Scholar 

  162. Gao, X. et al. Charcoal disrupts soil microbial communication through a combination of signal sorption and hydrolysis. ACS Omega 1, 226–233 (2016).

    Article  Google Scholar 

  163. Masiello, C. A. et al. Biochar and microbial signaling: production conditions determine effects on microbial communication. Environ. Sci. Technol. 47, 11496–11503 (2013).

    Article  Google Scholar 

  164. Pohl, K., Cantwell, M., Herckes, P. & Lohmann, R. Black carbon concentrations and sources in the marine boundary layer of the tropical Atlantic Ocean using four methodologies. Atmos. Chem. Phys. 14, 7431–7443 (2014).

    Article  Google Scholar 

  165. Currie, L. A. et al. A critical evaluation of interlaboratory data on total, elemental, and isotopic carbon in the carbonaceous particle reference material, NIST SRM 1649a. J. Res. Natl Inst. Stand. Technol. 107, 279–298 (2002).

    Article  Google Scholar 

  166. Mouteva, G. O. et al. Black carbon aerosol dynamics and isotopic composition in Alaska linked with boreal fire emissions and depth of burn in organic soils. Glob. Biogeochem. Cycles 29, 1977–2000 (2015).

    Article  Google Scholar 

  167. Flores-Cervantes, D. X., Plata, D. L., MacFarlane, J. K., Reddy, C. M. & Gschwend, P. M. Black carbon in marine particulate organic carbon: inputs and cycling of highly recalcitrant organic carbon in the Gulf of Maine. Mar. Chem. 113, 172–181 (2009).

    Article  Google Scholar 

  168. Yang, W. & Guo, L. Abundance, distribution, and isotopic composition of particulate black carbon in the northern Gulf of Mexico. Geophys. Res. Lett. 41, 7619–7625 (2014).

    Article  Google Scholar 

  169. Bird, M. I., Wynn, J. G., Saiz, G., Wurster, C. M. & McBeath, A. The pyrogenic carbon cycle. Annu. Rev. Earth Planet. Sci. 43, 273–298 (2015).

    Article  Google Scholar 

  170. Fassbender, A. J. et al. Perspectives on chemical oceanography in the 21st century: participants of the COME ABOARD meeting examine aspects of the field in the context of 40 years of DISCO. Mar. Chem. 196, 181–190 (2017).

    Article  Google Scholar 

  171. Hedges, J. I. et al. The molecularly-uncharacterized component of nonliving organic matter in natural environments. Org. Geochem. 31, 945–958 (2000).

    Article  Google Scholar 

  172. Andreae, M. O. & Gelencsér, A. Black carbon or brown carbon? The nature of light-absorbing carbonaceous aerosols. Atmos. Chem. Phys. 6, 3131–3148 (2006).

    Article  Google Scholar 

  173. Liu, X. et al. Intercomparison of equivalent black carbon (eBC) and elemental carbon (EC) concentrations with three-year continuous measurement in Beijing, China. Environ. Res. 209, 112791 (2022).

    Article  Google Scholar 

  174. Lack, D. A., Moosmüller, H., McMeeking, G. R., Chakrabarty, R. K. & Baumgardner, D. Characterizing elemental, equivalent black, and refractory black carbon aerosol particles: a review of techniques, their limitations and uncertainties. Anal. Bioanal. Chem. 406, 99–122 (2014).

    Article  Google Scholar 

  175. Brodowski, S., Rodionov, A., Haumaier, L., Glaser, B. & Amelung, W. Revised black carbon assessment using benzene polycarboxylic acids. Org. Geochem. 36, 1299–1310 (2005).

    Article  Google Scholar 

  176. Wiedemeier, D. B. et al. Aromaticity and degree of aromatic condensation of char. Org. Geochem. 78, 135–143 (2015).

    Article  Google Scholar 

  177. Kappenberg, A., Bläsing, M., Lehndorff, E. & Amelung, W. Black carbon assessment using benzene polycarboxylic acids: limitations for organic-rich matrices. Org. Geochem. 94, 47–51 (2016).

    Article  Google Scholar 

  178. Wurster, C. M., Saiz, G., Schneider, M. P. W., Schmidt, M. W. I. & Bird, M. I. Quantifying pyrogenic carbon from thermosequences of wood and grass using hydrogen pyrolysis. Org. Geochem. 62, 28–32 (2013).

    Article  Google Scholar 

  179. Haig, J., Ascough, P. L., Wurster, C. M. & Bird, M. I. A rapid throughput technique to isolate pyrogenic carbon by hydrogen pyrolysis for stable isotope and radiocarbon analysis. Rapid Commun. Mass Spectrom. 34, e8737 (2020).

    Article  Google Scholar 

  180. Maestrini, B. & Miesel, J. R. Modification of the weak nitric acid digestion method for the quantification of black carbon in organic matrices. Org. Geochem. 103, 136–139 (2017).

    Article  Google Scholar 

  181. Gustafsson, O. & Gschwend, P. M. The flux of black carbon to surface sediments on the New England continental shelf. Geochim. Cosmochim. Acta 62, 465–472 (1998).

    Article  Google Scholar 

  182. Lim, B. & Cachier, H. Determination of black carbon by chemical oxidation and thermal treatment in recent marine and lake sediments and cretaceous-tertiary clays. Chem. Geol. 131, 143–154 (1996).

    Article  Google Scholar 

  183. Dittmar, T. The molecular level determination of black carbon in marine dissolved organic matter. Org. Geochem. 39, 396–407 (2008).

    Article  Google Scholar 

  184. Ziolkowski, L. A., Chamberlin, A. R., Greaves, J. & Druffel, E. R. M. Quantification of black carbon in marine systems using the benzene polycarboxylic acid method: a mechanistic and yield study. Limnol. Oceanogr. Methods 9, 140 (2011).

    Article  Google Scholar 

  185. Druffel, E. R. M. et al. Marine organic carbon and radiocarbon — present and future challenges. Radiocarbon https://doi.org/10.1017/RDC.2021.105 (2022).

    Article  Google Scholar 

  186. Coppola, A. I., Walker, B. D. & Druffel, E. R. M. Solid phase extraction method for the study of black carbon cycling in dissolved organic carbon using radiocarbon. Mar. Chem. 77, 697–705 (2015).

    Article  Google Scholar 

  187. Wagner, S. et al. Online quantification and compound-specific stable isotopic analysis of black carbon in environmental matrices via liquid chromatography-isotope ratio mass spectrometry. Limnol. Oceanogr. Meth. 15, 995–1006 (2017).

    Article  Google Scholar 

Download references

Acknowledgements

A.I.C. acknowledges support from the Swiss National Science Ambizione grant ‘Fire in the Ocean’ (PZ00P2_185835) and thanks T. Eglinton, A. Varkalis and L. Tinkham. M.S. and T.D. acknowledge funding by the German Science Foundation (DFG) within the Cluster of Excellence EXC 2077 ‘The Ocean Floor — Earth’s Uncharted Interface’ (project number 390741603). N.D.W. acknowledges funding from the US Department of Energy (DOE)-funded COMPASS-FME project. Pacific Northwest National Laboratory (PNNL) is operated by Battelle for the US DOE under contract DE-AC05-76RL01830. Additional support was provided by the National Science Foundation OCE #2017577 (to S.W.). M.W.J. was funded by an independent research fellowship from the UK Natural Environment Research Council (NERC) (grant NE/V01417X/1).

Author information

Authors and Affiliations

Authors

Contributions

A.I.C., M.W.J. and C.S. started the first conceptualization of the review. A.I.C. was responsible for writing and project administration. S.T.L., A.I.C., M.W.J. and M.S. contributed to the box model conceptualization for oceanic black carbon and S.T.L. applied box model simulations using published rates. All authors contributed equally to writing in the original draft, review and editing.

Corresponding author

Correspondence to Alysha I. Coppola.

Ethics declarations

Competing interests

The authors declare no competing interests.

Peer review

Peer review information

Nature Reviews Earth & Environment thanks Rebecca Abney, and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

Additional information

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Glossary

Black carbon

(BC). A carbonaceous, polycondensed aromatic product (>60% organic carbon) derived from the incomplete combustion of biomass and fossil fuels, with greater environmental persistence than its unburned biomass source.

Labile

Compounds that experience rapid turnover within hours to days of release and do not accumulate.

Environmentally persistent

Compounds that resist rapid microbial degradation, accumulating on land and in the ocean for centuries to millennia.

Dissolved black carbon

(DBC). The black carbon fraction measured within dissolved organic carbon.

Particulate black carbon

(PBC). The black carbon fraction in solid environmental matrices, such as particulate organic carbon, soils and sediments.

Dissolved organic carbon

(DOC). Organic carbon dissolved in water that passes through a filter, usually with a pore size of 0.1 to 0.7 µm.

Particulate organic carbon

(POC). Organic carbon suspended in water that is retained on a filter, usually with a pore size of 0.1 to 0.7 µm.

PM2.5

Fine particle matter 2.5 µm or smaller in size.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Coppola, A.I., Wagner, S., Lennartz, S.T. et al. The black carbon cycle and its role in the Earth system. Nat Rev Earth Environ 3, 516–532 (2022). https://doi.org/10.1038/s43017-022-00316-6

Download citation

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s43017-022-00316-6

This article is cited by

Search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing