Abstract

A decade of widespread increases in surface water concentrations of total organic carbon (TOC) in some regions has raised questions about longer term patterns in this important constituent of water chemistry. This study uses near-infrared spectroscopy (NIRS) to infer lake water TOC far beyond the decade or two of observational data generally available. An expanded calibration dataset of 140 lakes across Sweden covering a TOC gradient from 0.7 to 24.7 mg L-1 was used to establish a relationship between the NIRS signal from surface sediments (0-0.5 cm) and the TOC concentration of the water mass. Internal cross-validation of the model resulted in an R (2) of 0.72 with a root mean squared error of calibration (RMSECV) of 2.6 mg L-1. The TOC concentrations reconstructed from surface sediments in four Swedish lakes were typically within the range of concentrations observed in the monitoring data during the period represented by each sediment layer. TOC reconstructions from the full sediment cores of four lakes indicated that TOC concentrations were approximately twice as high a century ago.

Keywords

Carbon cycling; Dissolved organic carbon; Near infrared spectroscopy (NIRS); Paleolimnology; Sediment; Sweden

Published in

Journal of Paleolimnology
2011, Volume: 45, number: 4, pages: 507-518

SLU Authors

• Bishop, Kevin

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

Associated SLU-program

Lakes and watercourses
Climate
Acidification


UKÄ Subject classification

Fish and Aquacultural Science
Environmental Sciences related to Agriculture and Land-use


Publication identifier

DOI: https://doi.org/10.1007/s10933-010-9420-x

Permanent link to this page (URI)

https://res.slu.se/id/publ/37600