The Productivity of a Range of Blanket Bog Vegetation Types in the Northern Pennines

Total and component net production of seven blanket bog sites in the northern Pennines, representing a range of variation in floristic composition, was estimated. There was a two-fold variation in production between sites (481-868 g m-2yr-1), the mean total annual net production for all seven sites studied being 659 ± 53 g m-2yr-1. Between-year variation was relatively small in comparison to that between sites. The sites with the highest production were those which had been recently burnt. For the remaining sites, assumed to be in a steady state situation, there was a trend of decreasing production with increasing wetness, reflecting decreasing contribution of Calluna and Eriophorum vaginatum only partly replaced by increased Sphagnum growth on the wetter sites. Mean production per growing season day for the four Calluneto-Eriophoretum sites was 1.98 g m-2day-1. The total production of the 1215 ha of blanket bog within the Moor House National Nature Reserve was estimated as 7.67 × 106kg yr-1.