Plant community shift across sharp soil moisture
transition at the Kungsängen meadow
The plant community was assessed in plots along two permanent transects
stretching from the wetter part close to the Fyris river to a mesic-dry
part of the meadow (Fig. 1). A total of 85 plant species were recorded
along transects 1 and 4 (73 and 61 species, respectively; Supplementary
datafile 3), with the highest numbers, 24–29 plant species, recorded in
plots 13–16 in transect 1 (Fig. S2), just on the mesic-dry side of the
moisture transition. In accordance with earlier inventories (Sernander,
1948; Zhang, 1983), the number of recorded plant species dropped rapidly
in the wet part of the meadow with on average only six species per plot
across plots 17–25. There is a slight levee along the river where the
number of recorded species increases again (Fig. S2). nMDS ordination of
the plant community along transects 1 and 4 demonstrates the distinct
separation between plots in the mesic-dry part east of the soil sampling
compared to the wet part west of the soil sampling (Fig. 2), and with a
transition from Carex disticha to Carex acuta dominance at
the border (Zhang, 1983). Alopecurus pratensis andStellaria graminea were detected in all plots in the mesic-dry
area and Poa trivialis , Phleum pratense andTrifolium repens were other highly abundant species in the
mesic-dry area (Supplementary datafile 3). Fritillaria meleagriswas frequent in plots in the mesic-dry part to the east of the soil
sampling (and also in elevated plots closest to the river) but did not
occur in the wetter parts of the transects (Fig. S2). The distinctC. acuta dominated community in the wet side of the meadow has
been previously reported (Zhang, 1983). Other frequently observed
species in the wet area include Equisetum fluviatile , Carex
disticha and Galium
palustre .
Soil sampling in early June confirmed that mean gravimetric soil
moisture was significantly different (p<0.001; t = -5.1812,
nwet = 10; ndry = 10) on either side of
the plant community transition border, with 76% and 34% soil moisture
in the wet compared to the mesic-dry side of the meadow (Fig. S3).
Characterizing the belowground
microeukaryotic community composition