Figure captions:

Figure 1: Rainfall and water table depth for deep (a) and shallow (b) main sites. Sites with large and small catchments are represented by maroon and black lines, respectively. A flat line indicates when the water table was lost from the site.
Figure 2: Time series of tension at 5 cm depth (maroon lines) and VWC0–3 cm (black solid lines), for S. fallax(white-filled circles) and S. palustre (grey-filled squares) between DOY 176 (June 25th) and DOY 211 (July 30th) at the shallow sites (S). Large (L) catchment area sites are shown on the left, while small (S) catchment area sites are shown on the right. Water table depth (WTD - black dotted lines) is shown relative to the moss surface. Date of water table loss is indicated by a vertical dashed line.
Figure 3: Time series of tension at 5 cm depth (maroon lines) and VWC0-3 cm (black lines) for S. fallax(white-filled circles) and S. palustre (grey-filled squares) between DOY 176 (June 25th) and DOY 211 (July 30th) at the deep sites (D). Large (L) catchment area sites are shown on the left, while small (S) catchment area sites are shown on the right. Water table depth (WTD - black dotted lines) is shown relative to the moss surface.
Figure 4: Relation between water table depth and volumetric water content in the top 3 cm (a and b), and tension at 5 cm depth (c and d) for deep (a and c) and shallow (b and d) sites. Shallow sites lost their water table (denoted by ‘no WT’ ) with ‘no WT’ data shown as boxplots for S. fallax (black) and S. palustre(maroon). A 1:1 relation between tension and WTD is shown as a black solid line.
Figure 5: Box plot of tension measured at 5 cm depth during the mid-summer drought intensive field survey (DOY 221) for deep and shallow sites based on catchment size (a) and Sphagnum species (b). Letters denote significant pairwise differences, where the significance of one-way interactions Depth×Catchment and Depth×Species are shown in (a) and (b), respectively.
Figure 6: Lab-measured chlorophyll fluorescence stress metric forSphagnum fallax (black) and Sphagnum palustre (maroon) samples during a drying experiment. The stress metric is the variable fluorescence over the maximum quantum yield (Fv/Fm) of dark-adapted samples. Empirical relations between Fv/Fm and volumetric water content (VWC) are shown using a rectangular (dashed lines) hyperbola. High and low VWC stress thresholds (dotted lines) represent the 25% and 75% of the maximum modelled Fv/Fm.

Figure 1