Variation in habitat factors and species composition of Scorpidium scorpioides communities in NW-Europe

Abstract

To assess the natural range in habitat parameters of the once common rich-fen bryophyte Scorpidium scorpioides, water chemistry and vegetation were studied in different regions characteristic of its NW-European distribution area: the Netherlands, Ireland, Denmark and Fennoscandia. Scorpidium scorpioides was found in an environment with circumneutral pH. The variation in solute content and composition was large and nutrient (N and P) concentrations ranged from zero to values indicative of more eutrophic conditions. Six different vegetation types with S. scorpioides were distinguished, resembling Caricion davallianae, Caricion curto-nigrae and HydrocotyloBaldeUion communities. Type of substrate and solute levels were strongly correlated with the first ordination axis (DCA) and nutrient status and geographic position with the second axis. Habitat and vegetation characteristics in Dutch rich-fens with S. scorpioides indicated that mineral status was higher than in Fennoscandia and Ireland; solute-poor habitats with S. scorpioides have disappeared from the Netherlands. Trophic status was higher in the Netherlands than in Fennoscandia, but in some cases lower than in Ireland. Acidification and eutrophication may have played a role in the decrease of the species in the Netherlands. However, the wide ecological ranges suggest that the decrease of S. scorpioides is not a physiological effect of unsuitable environmental conditions per se.

Changes in nutrient availability from calcareous to acid wetland habitats with closely related brown moss species: increase instead of decrease in N and P

“…Scorpidium spp. generally occur at low P-levels, and disappear when P-availability becomes too high (Kooijman and Hedenäs 1991;Kooijman and Westhoff 1995). In the present study, even the Dutch S. scorpioides fens were (still) P-limited.…”

The role of elevated atmospheric CO<sub>2</sub> and increased fire in Arctic amplification of temperature during the Early to mid-Pliocene

“…scorpioides (Kooijman and Westhoff, 1995;Kooijman and Paulissen, 2006) and is higher than what would be expected for peat-bog sediments that are acidic (pH 3-6; Clymo, 1964) and which constitute most of the peats studied by Naafs et al (2017). 30…”

Calliergon megalophyllum rediscovered in the Netherlands after 50 years: comparison to Swedish habitats

“…However, the particular habitat conditions of high pH, but low buffer capacity suggest that acidification has played at least some role, similar to the disappearance of weakly buffered habitats with S. scorpioides (Kooijman and Westhoff 1995). In addition, pollution of surface waters in the 1960s may have led to local extinction, although C. megalophyllum is a relatively eutrophic species and can at least stand slightly elevated nutrient levels, such as in the new Dutch locality.…”