Sphagnum spore banks in two montane peatlands at different elevations

Abstract

Spore production of bryophytes is common in subalpine ecosystems, but how spore banks of bryophytes vary with elevations is unknown. We used peat cores from two Sphagnum dominated peatlands, a low- (780 m a.s.l.) and a high-elevation (1480 m a.s.l.) site to test the hypotheses that spore concentration, accumulation rate, germinability and longevity are lower at a high-elevation peatland than those at lower elevation due to the assumed climatic limitations at high elevation. Along the cores, Sphagnum spores were extracted, burial time of spores was dated and spore germinability was tested layer by layer. Sphagnum spore concentration, accumulation rate and germinability were greater at the high-elevation peatland than at the low-elevation site. Both peatlands had long-term persistent Sphagnum spore banks with a predicted longevity (the burial time when 1% spores are viable) of c. 390 and 140 years for the low- and high-elevation sites, respectively. Our study suggests that Sphagnum, the ecological engineer of peatlands, by regulating spore production and longevity can maintain relatively constant spore banks which may be of great importance in population regeneration and persistence in a changing world.