Snowpack controls on soil nitrogen dynamics in the Colorado alpine

Mineralization and nitrification inputs to the soil inorganic N pool were an order of magnitude higher than snowmelt inputs and were controlled by the timing and depth of snowpack accumulation. Ion exchange resin bags located at the soil surface indicated that the actual N inputs at any location were highly variable. About 90% of isotopically labelled ¹⁵NH₄ ⁺ applied to the snow surface before melt was recovered in soil pools. The timing and depth of snowpack accumulation plays a key role in nitrogen cycling in alpine ecosystems and may control inorganic nitrogen export in surface waters. -from Authors