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Background: Liverwort heath is considered in Scotland to be one of the vegetation types most vulnerable to environmental change, yet detailed insights into its dynamics are lacking.Aims: To assess the nature and extent of plant compositional changes in liverwort heath over 50 years and relate this to environmental change drivers.Methods: Vegetation plots previously recorded 20 and 50 years ago were re-surveyed to assess changes in species composition, plot-level species richness and between-plot variability, using several β-diversity indices and partitioning. The environmental indicator values of the species that showed most change were used to identify the environmental drivers of change.Results: Liverwort heath in north-west Scotland has undergone compositional changes over 50 years, becoming more heterogeneous, and losing some of its distinct character. Dwarf shrubs and specialist liverworts have decreased, while graminoids have increased. Partitioning of change in β diversity indicated that mainly cha...

Background: The effect of the anticipated climate change on the stability of vegetation and the factors underlying this stability are not well understood. Aims: Our objective was to quantify long-term vegetation changes in a range of habitats in northern Europe by exploring species co-occurrences and their links to diversity and productivity gradients. Methods: We re-sampled vegetation in 16 arctic, mountain and mire sites 20 to 90 years after the original inventories. A site-specific change in species assemblages (stability) was quantified using species co-occurrences. Using a randomisation test we tested whether the changes observed were significantly greater than those expected by chance. Relationships between patterns in vegetation stability and time between surveys, numbers of plots, or species diversity and proxies for productivity, were tested using regression analysis. Results: At most sites the changes in species co-occurrences of vascular plants and bryophytes were greater than those expected by...

Background: Re-visitation studies are often based on phytosociological survey data where the precise location of the original plots is unknown. Attempts to evaluate the error associated with relocation uncertainty are rare, yet this is important in interpreting the results with any degree of confidence. Aims: Using a 50-year re-visitation study of upland vegetation in the Scottish Highlands, we aim to assess the potential for, and implications of, uncertainty in relocating plots. Methods: At nine sites, three to five replicate plots were surveyed within a stand of vegetation relocated to the nearest 100 m using the original plot location data. Results: The compositional difference (measured by the Bray–Curtis distance) between the original plot and new replicate plots was greater than that among the replicate plots, both for the combined data and individual vegetation types. Temporal species turnover was greatest in the lower cover-abundance categories (< 5%). Conclusions: We demonstrate that if temporal ...