Ecological distribution of the water grimmia (Schistidium agassizii Sull. & Lesq.), a nationally scarce semi-aquatic moss in the U.K., with a new record from an upland tributary of the River Dee, N.E. Scotland

摘要

Bryophytes comprise a highly successful group of plants that have managed to exploit environmental conditions generally unsuitable for sustaining vascular plant growth (Stream Bryophyte Group; 1999; Lang, 2010). For example, in fast flowing and boulder-strewn upland headwater streams, bryophytes are often the dominant form of plant life, tolerating being pummeled by harsh current velocities and dislodged or rolling substratum (Lang, 2010; Lang & Murphy, 2012). These stream bryophytes encompass a relatively small proportion of the moss and liverwort flora capable of occupying habitats frequently inundated with water (Stream Bryophyte Group, 1999). Recent work has placed emphasis on the potential value of bryophyte communities for making integrated bioassessments of water quality, and through their prevailing life strategies, also reveal important information concerning the physical character of rivers (Lang & Murphy, 2012; Vieira et al, 2012).