Community water content (CWC) was measured across the site in January 2008. Sponge cores, 2–3 cm diameter and 3 cm depth,were inserted into the moss beds adjacent to each quadrat, and were retrieved after 24 h. The sponges were placed in airtight tubes,returned to the laboratory within 1 h and weighed to determine fresh weight. The sponges were then left to dessicate in the laboratory, at a relative humidity of 22%, until a constant dry weight was reached. This method has been shown to give a good correlation with true turf water content while avoiding destructive analysis of the vegetation (Robinson and King unpublished data). The CWC was calculated as Community water content (CWC) was measured across the site in January 2008. Sponge cores, 2–3 cm diameter and 3 cm depth,were inserted into the moss beds adjacent to each quadrat, and were retrieved after 24 h. The sponges were placed in airtight tubes,returned to the laboratory within 1 h and weighed to determine fresh weight. The sponges were then left to dessicate in the laboratory, at a relative humidity of 22%, until a constant dry weight was reached. This method has been shown to give a good correlation with true turf water content while avoiding destructive analysis of the vegetation (Robinson and King unpublished data). The CWC was calculated as