Tundra vegetation types in the study area, the Fuglebekken catchment (Hornsund, Svalbard), based on the field botanical survey.

* Soils and tundra classification after Szymański et al. [28].^ The total catchment area is 1,385,939 m2 and tundra covers 1,282,195 m2 (excluding not vegetated areas, e.g. moraine and lakes).^^ Bird-N [%] given as percentage of N assimilated from this source in relation to two other sources (N2-fixation and atmospheric deposition), in brackets are given possible ranges (minimum and maximum) depending on two other sources.For location see Fig 1. Note that tundra T-WTM was subdivided into two categories depending on location (AB).