Swedish forest defies climate pollution theory, puzzles researchers
A 72-year study of an old-growth Swedish forest reveals vegetation patterns that contradict assumptions about nitrogen pollution damage to northern ecosystems. The finding suggests local forest dynamics—not regional pollution trends—drive ecological change, complicating efforts to predict how climate stress will reshape forests across Europe.
Originaltitel: Vegetation dynamics 1946–2018 in an old‐growth conifer forest
<p>We analysed ground vegetation in 250 plots in 2018 in the old-growth Picea abies-dominated forest Säby Västerskog, south-east Sweden as a follow-up of studies in 1946 and 1998 with the same layout of plots. The vegetation changes were not clearly directional: the species composition in 2018 was intermediate between that of 1946 and 1998, whereas in 1998 species richness was higher and with the unique presence of a number of species indicating small-scale disturbances. Vaccinium myrtillus increased in cover since 1946 and Avenella flexuosa decreased. This goes against regional trends that have been attributed to nitrogen deposition. Regional changes are overshadowed by local dynamics.</p>