Biogeochemistry

, Volume 70, Issue 3, pp 369–402

Trends in Dissolved Organic Carbon in UK Rivers and Lakes

  • Fred Worrall
  • Ron Harriman
  • Chris D. Evans
  • Carol D. Watts
  • John Adamson
  • Colin Neal
  • Ed Tipping
  • Tim Burt
  • Ian Grieve
  • Don Monteith
  • Pam S. Naden
  • Tom Nisbet
  • Brian Reynolds
  • Paul Stevens
Article

DOI: 10.1007/s10533-004-8131-7

Cite this article as:
Worrall, F., Harriman, R., Evans, C.D. et al. Biogeochemistry (2004) 70: 369. doi:10.1007/s10533-004-8131-7

Abstract

Several studies have highlighted an increase in DOC concentration in streams and lakes of UK upland catchments though the causal mechanisms controlling the increase have yet to be fully explained. This study, compiles a comprehensive data set of DOC concentration records for UK catchments to evaluate trends and test whether observed increases are ubiquitous over time and space. The study analysed monthly DOC time series from 198 sites, including 29 lakes, 8 water supply reservoirs and 161 rivers. The records vary in length from 8 to 42 years going back as far as 1961. Of the 198 sites, 153 (77%) show an upward trend in DOC concentration significant at the 95% level, the remaining 45 (23%) show no significant trend and no sites show a significant decrease in DOC concentration. The average annual increase in DOC concentration was 0.17 mg C/l/year. The dataset shows: (i) a spatial consistent upward trend in the DOC concentration independent of regional effects of rainfall, acid and nitrogen deposition, and local effects of land-use change; (ii) a temporally consistent increase in DOC concentration for period back as far as the 1960s; (iii) the increase in DOC concentration means an estimated DOC flux from the UK as 0.86 Mt C for the year 2002 and is increasing at 0.02 Mt C/year. Possible reasons for the increasing DOC concentration are discussed.

Keywords

Climate changeDOCLakesRiversTrends

Copyright information

© Kluwer Academic Publishers 2004

Authors and Affiliations

  • Fred Worrall
    • 1
  • Ron Harriman
    • 2
  • Chris D. Evans
    • 3
  • Carol D. Watts
    • 4
  • John Adamson
    • 5
  • Colin Neal
    • 4
  • Ed Tipping
    • 6
  • Tim Burt
    • 7
  • Ian Grieve
    • 8
  • Don Monteith
    • 9
  • Pam S. Naden
    • 4
  • Tom Nisbet
    • 10
  • Brian Reynolds
    • 3
  • Paul Stevens
    • 3
  1. 1.Department of Earth SciencesScience LaboratoriesDurhamUK
  2. 2.The Freshwater LaboratoryFaskallyPitlochryUK
  3. 3.Centre for Ecology and HydrologyUniversity of WalesBangorUK
  4. 4.Centre for Ecology and HydrologyWallingfordUK
  5. 5.Environmental Change Network, Centre for Ecology and HydrologyMerlewoodGrange over SandsUK
  6. 6.Centre for Ecology and HydrologyFerry HouseFar Sawrey, AmblesideUK
  7. 7.Department of GeographyScience LaboratoriesDurhamUK
  8. 8.Department of Environmental ScienceUniversity of StirlingStirlingUK
  9. 9.Environmental Change Research CentreUniversity College LondonLondonUK
  10. 10.Forest ResearchAlice Holt lodgeFarnhamUK