Snowmelt Water Retention and Associated Nitrate Redistribution using UAV in Arctic Tundra

Abstract:

Nutrient availability, particularly nitrogen, in Arctic ecosystems is key for biological activity, and thereby directly linked to tundra vegetation response to Climate Change in the Arctic. We have modeled the redistribution of meltwater following snowmelt, the accumulation of meltwater, and the dissolved nitrate at landscape scale in a tundra landscape with discontinuous permafrost. This is achieved by combining UAV imagery, snow chemistry, and hydrological modeling. We argue that the majority of deposited nitrate in the winter snowpack may be flushed out from terrestrial to aquatic environments due to a limited storage capacity in landscapes with permafrost. Using high-resolution topographical modeling and network-based flow routing, we demonstrate that micro-topography is a crucial parameter to quantify landscape retention capacity of meltwater, and the associated soluble ions. Our study presents a workflow that tracks how evenly distributed nitrate during winter may be heavily redistributed during initial snowmelt with implications for plant diversity and growth during spring.