Terrestrial organic carbon storage in a British moorland

Accurate estimates for the size of terrestrial organic carbon (C) stores ar e needed to determine their importance in regulating atmospheric CO2 concen trations. The C stored in vegetation and soil components of a British moorl and was evaluated in order to: (i) investigate the importance of these ecos ystems for C storage and (ii) test the accuracy of the United Kingdom's ter restrial C inventory. The area of vegetation and soil types was determined using existing digitized maps and a Geographical Information System (GIS). The importance of evaluating C storage using 2D area projections, as oppose d to true surface areas, was investigated and found to be largely insignifi cant. Vegetation C storage was estimated from published results of producti vity studies at the site supplemented by field sampling to evaluate soil C storage. Vegetation was found to be much less important for C storage than soil, with peat soils, particularly Blanket bog, containing the greatest am ounts of C. Whilst the total amount of C in vegetation was similar to the U K national C inventory's estimate for the same area, the national inventory estimate for soil C was over three times higher than the value derived in the current study. Because the UK's C inventory can be considered relativel y accurate compared to many others, the results imply that current estimate s for soil C storage, at national and global scales, should be treated with caution.