GEOCHEMICAL SURVEY OF MOUNT BAKER, WASHINGTON

Temperate alpine glaciers, such as those found within the North Cascades, are important because they are key indicators of climate change, crucial sources of freshwater, and are rapidly retreating. Little is known about the role of microbial communities in the North Cascade glacier ecosystems, however, other temperate glacial systems are influenced by microbial communities. On Mount Baker dense concentrations of pink-pigmented algal cells known as Chlamydomonas nivalis, a species of green algae that thrives in cold environments, were observed. In situ measurements of several biogeochemical parameters were collected from the snowpack and glacial outflow including conductivity, temperature, light intensity, chlorophyll a (CHLa), and colored dissolved organic matter (CDOM). Three samples of distinctly pigmented snow (white, brown, and pink) were collected with the goal of determining differences in microbial communities as well as geochemical relationships within the snow. Here we observed a correlation between snow pigment and cell concentration, CHLa, CDOM, and virus like particle (VLP) concentrations. The pink and brown snow samples had higher cell concentrations on average than the white snow by a factor of ten. Likewise, VLP concentrations displayed a similar trend. The pink and brown snow were also higher in CHLa than the white snow by a factor of 100, whereas measurements in CDOM did not differ between pigmented snow samples. This work provides initial biogeochemical parameters for future understanding of the role that microbes have in alpine glacial snowpack.