Nutrient cycling and productivity of a Himalayan Glacier Surface

Nutrients deposited and cycled on the glacier surfaces are important not only because of their role in the global biogeochemical cycling in the downstream environments, but also because of their importance as a primary food source for microbes inhabiting glacial surfaces, their ice surface darkening properties, and the consequent potential for enhancing glacier melt. The present study focuses on the Chhota Shigri (CS) Glacier in the North-Western (NW) Indian Himalayan region. The dissolved organic carbon (DOC) concentration in the bare ice is relatively higher than the other aspects studied in the glacial environment of CS indicating that much of the active microbial activity occurring in the bare ice. Total inorganic nitrogen (TIN) is typically concentrated in the snow, which is the major contributor of NO₃^-. The rapid declining of TIN in the bare ice as compare to other aspects and its enrichment in DOC suggests for a more active microbial activity occurrence in the exposed ice rather than in isolated cryoconites holes in the Chhota Shigri Glacier. The net biological productivity indicates the dominance of net gross photosynthesis over respiration, suggesting a net autotrophic production in CS.