Dataset: Broadbalk soil organic carbon content 1843-2010

Broadbalk: Changes in soil organic carSbon t/ha (0-23cm ) figure

Broadbalk: Changes in soil organic carSbon t/ha (0-23cm ) figure


Long-term changes in soil organic carbon content (t/ha) in selected treatments of the Broadbalk experiment, where winter wheat has been grown every year since autumn 1843. SOC in t/ha, calculated from %SOC and soil weights, adjusted for changes in soil bulk density in FYM treatments.


Soil organic carbon has been measured at intervals since 1865. Data is mean of sections 1, 6 and 9, continuous winter wheat (except for occasional fallow), from six selected plots (3, 5, 8, 2.1, 2.2 and 1). The starting values in 1843 and the later FYM treatments have been estimated. The sections were regularly fallowed from 1926 to 1967, FYM was not applied in fallow years (shown as dashes in the figure). Lime (chalk) has been applied since the 1950s to maintain soil pH at a level which does not limit yield. Herbicides were introduced in 1964; previously weeds were controlled by cultivation or fallowing. Modern high-yielding cultivars have been used since 1968. Spring and summer fungicides have been applied as necessary since 1978.

Technical Information

Soil samples taken in 1881, 1893, 1914, 1936 and 1944 were re-analysed in 2001-4 for total C by combustion (LECO) and CaCO3-C by manometry. SOC is calculated as Total C minus CaCO3-C. Data in 1865 are derived from the original Soda Lime analyses (for Total N) and C:N ratios for 1893 (for organic C). Data for 1966 are corrected Walkey-Black values for organic C. Data for 1987 are Tinsley for organic C. Data for 1992 onwards are Total C by combustion (LECO) minus CaCO3-C by manometry.

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  • Nathalie Castells-Brooke: Data manager
  • Margaret Glendining: Data curator
  • Sarah Perryman: Data curator
  • Andrew Macdonald: Project leader
  • Paul Poulton: Researcher
  • Ruth Skilton: Data collector
  • Jeanne Day: Data collector
  • Daniel Hampshire: Data collector

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Rothamsted Research


Creative Commons License This dataset is available under a Creative Commons Attribution Licence (4.0).

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YOU MUST CITE AS: Rothamsted Research (2014). Dataset: Broadbalk soil organic carbon content 1843-2010 Electronic Rothamsted Archive, Rothamsted Research

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Table Of Contents

Soil organic carbon, t/ha in topsoil (0-23cm from the following plots):

  • Plot 3: no fertilizer or manure since 1852
  • Plot 5: PKMg since 1852
  • Plot 8: PKMg + 144 kg N since 1852
  • Plot 2.2: 35t FYM (farmyard manure) since 1843
  • Plot 2.1: 35t FYM since 1885 + 96 kgN since 1968
  • Plot 1: 35t FYM +NPK 1968-2000; 192kgN only since 2001

This dataset is derived from measurements made by the Analytical Chemistry Unit, Rothamsted Research, Harpenden. The data presented is mean data from selected plots and sections only. The complete data set, including the raw data used to derive the mean values, is available from the e-RA curators.

The Analytical Chemistry Unit follows the Joint Code of Practice (JCoPR) and participates in European Quality Assurance programmes. All performance is strictly monitored using certified external standards alongside in-house standard materials. Standards and check samples are monitored and recorded.

For further information and assistance, please contact the e-RA curators, Sarah Perryman and Margaret Glendining using the e-RA email address: