Data from: Partitioning beta diversity at two spatial resolutions reveals biotic homogenisation with habitat degradation

This data pertains to lichen, fungi, and bryophyte species composition
from 120 forest sites across Sweden.  The data is from a detailed
species inventory by species experts in 2021 and 2021 in two regions in
Sweden: Hälsingland and Värmland. For each taxa we have assemblage data
from 20m radius plots in three different forest management types: Young
forests (clearcut 20-30 years ago), Retention Patches (small patches of
forest left unharvested during the young forest's harvesting phase
20-30 years ago), and Set-asides (larger patches of forest left
unharvested partly for biodiversity conservation. These three forest
management types reflect three different levels of habitat degradation:
high degradation (young forest), medium degradation (retention patches),
and low degradation (set-asides). Using this data, we used beta diversity
partitioning to assess how community composition varied between habitat
degradation level. We examined how pairwise total beta diversity,
nestedness, and turnover varied when comparing assemblages from sites of
either the same or different habitat degradation levels. In addition, we
examined the relationship between total beta diversity, nestedness and
turnover when assemblages pooled at the habitat degradation level were
compared. We detected a small increase in pairwise lichen total
beta diversity (Cliffs delta 0.40) and nestedness (Cliffs delta 0.19), but
not in any other pairwise comparisons. In contrast, for all taxa,
comparisons between assemblages pooled at the habitat degradation level
showed higher values of nestedness and lower values of turnover than the
corresponding pairwise comparisons, suggesting biotic homogenisation in
highly degraded sites. This data has potential for exploring how
communities are assembled across different types of land management and
between taxa.