The Effect of Coniferous Litter and Different Snow Meltwaters upon the Growth of Two Species of Snow Algae in Axenic Culture

Abstract

Dust and coniferous litter covering snowbanks are potentially important sources of nutrition for algae living in snow. Two species of snow algae, Raphidonema nivale and Chloromonas pichinchae∗∗∗, were investigated for the effects that extracts from coniferous litter and different snow meltwaters would have upon their growth and development. The algae were collected from snow under coniferous trees near Mt. Stuart, Washington, and isolated into axenic culture. Laboratory experiments indicated positive growth responses for C. pichinchae grown in extracts of coniferous leaves, bark, and pollen, and positive, neutral, and negative responses for R. nivale grown in extracts of leaves and bark. These results corresponded to observations made in the field where C. pichinchae was much more abundant than R. nivale in snowbanks located under coniferous-tree canopies. Neither species of snow algae responded to extracts from cone scales. Considerable morphological abnormality occurred in cells of R. nivale grown in high concentrations of Pinus contorta bark extract. Individual cells showed ballooning effects, and cytological structures were atypical when compared to cells in normal filaments. Chloromonas pichinchae responded differently to snow meltwater collected at three elevations near Mt. Stuart. The alga grew best in snow meltwater collected under a coniferous-tree canopy, and this sample contained the highest concentration of inorganic PO₄-P. It was concluded that materials leached from dust and coniferous litter contribute to the chemical composition of snow and to the growth of snow algae.