Biogeosciences www.biogeosciences.net 1726-4170 1726-4189 6 2 2009 10.5194/bg-6-275-2009 http://www.biogeosciences.net/6/275/2009/ http://www.biogeosciences.net/6/275/2009/bg-6-275-2009.html http://www.biogeosciences.net/6/275/2009/bg-6-275-2009.pdf 275 284 2009-02-25 Towards spatial assessment of carbon sequestration in peatlands: spectroscopy based estimation of fractional cover of three plant functional types G. Schaepman-Strub gabriela.schaepman@wur.nl J. Limpens M. Menken H. M. Bartholomeus M. E. Schaepman Nature Conservation and Plant Ecology Group, Wageningen University, Wageningen, The Netherlands Centre for Geo-information, Wageningen University, Wageningen, The Netherlands Peatlands accumulated large carbon (C) stocks as peat in historical times. Currently however, many peatlands are on the verge of becoming sources with their C sequestration function becoming sensitive to environmental changes such as increases in temperature, decreasing water table and enhanced nitrogen deposition. Long term changes in vegetation composition are both, a consequence and indicator of future changes in C sequestration. Spatial continuous accurate assessment of the vegetation composition is a current challenge in keeping a close watch on peatland vegetation changes. In this study we quantified the fractional cover of three major plant functional types (PFTs; <i>Sphagnum</i> mosses, graminoids, and ericoid shrubs) in peatlands, using field spectroscopy reflectance measurements (400–2400 nm) on 25 plots differing in PFT cover. The data was validated using point intercept methodology on the same plots. 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