Type of broadleaf forest matters most for ptyctimous mite communities (Acari, Oribatida) in Norway

We studied ptyctimous moss mites, which are characteristic of forest
habitats, in Norwegian broadleaf forests considered as biodiversity
hotspot areas in Fennoscandia. The study aimed to evaluate the effect of
different factors (regional locality, annual precipitation, mean annual
temperature, forest type, forest wetness and microhabitat) on the
ptyctimous mites and on discovering their richness in broadleaf forests.
Samples were collected from nine broadleaf forests in western, southern
and eastern Norway, in different climatic conditions, six forest types,
three forest wetness states and eight microhabitats. Overall, 3,341
ptyctimous mites were collected and their abundance differed significantly
among the regions, forest types and microhabitats. Forest type turned out
to be the most important factor, responsible for 24.5% of the total
variation in the abundance of the ptyctimous mites. Other important
factors were forest wetness and microhabitat. In total, 27 species, i.e.,
87% of all ptyctimous mites known from before in Norway were found and the
species richness was highest in the east and lowest in the west of the
country. Atropacarus striculus was most common and most abundant; it made
nearly 30% of all ptyctimous mites collected. On the other hand, a quarter
of the species were represented by less than 10 specimens; most of these
were new records for Norway. Among ten species discovered as new to
Norway, four were also new to Fennoscandia. These findings confirm the
unique character and high biological diversity of Norwegian broadleaf
forests.