摘要：We quantitatively investigated a snow algal community on Tyndall Glacier of the Southern Patagonia Icefield, Chile, at an elevation from 300 to 1500 m a.s.l. We observed 7 species of snow and ice algae (Chlorophyta and cyanobacteria) on the glacier. These species were Mesotaenium (M.) berggrenii , Cylindrocystis (Cyl.) brébissonii , Ancylonema sp., Closterium sp., Chloromonas sp., Oscillatoriaceae cyanobacterium, and an unknown alga. The spatial distribution of these algae differed among the species. M. berggrenii , Cyl. brébissonii , Ancylonema sp., and Closterium sp. appeared mainly in the lower-elevation area (370–770 m a.s.l.), the unknown alga in the higher-elevation area (900–1500 m a.s.l.), and Chloromonas sp. and Oscillatoriaceae cyanobacterium in the middle part of the glacier. The mean cell concentration and total cell volume biomass ranged from 0 to 9.2 × 10 4 (mean: 1.8 × 10 4 ) cells mL −1 , from 0 to 327 (mean: 63) μL m −2 , respectively. The cell volume biomass generally decreased with altitude. The community structure showed that M. berggrenii was dominant in the ice area (65–100% of total cell volume) and lower snow area (50–70%) and that the unknown alga was dominant in the higher snow area (100%). The Simpson’s species diversity index was significantly different among the study sites but was generally low (less than 1.9) at all sites. The cell volume biomass and diversity index are relatively smaller on the Patagonian glacier than those in algal communities on Alaskan and Himalayan glaciers. Lower nutrient levels in precipitation are likely to cause the smaller algal biomass on the glacier.
