Coupled hydrology and biogeochemistry of arctic hillslopes

Stream networks are poorly developed in arctic catchments, and hillslopes are primarily drained not by stream channels, but by water tracks, linear preferential flowpaths that connect surface and subsurface soils to the valley bottom and stream networks. As such water tracks may propagate the biogeochemical consequences of changing precipitation and thawing permafrost to downstream ecosystems, or they may mitigate such changes by transforming or retaining materials. In this project we are evaluating the hydrology and biogeochemistry of water tracks. We are determining how hydrologic gradients, sources of water, and storm hydrograph responses change with thawing of the soil profile. We are concurrently estimating fluxes of solutes, as well as estimating rates of nutrient uptake within water tracks. As a preferential flowpath, water tracks offer the opportunity to quantify nutrient spiraling parameters, and compare the relative importance of reaction and transport for solute fluxes from hillslopes. Field work for this project is based out of the Toolik Field Station.

Funded by the Office of Polar Programs, National Science Foundation